The Fortymile River region in east-central Alaska has a long and colorful history as the site of the first major gold discovery in interior Alaska. Placer gold has been mined in the region nearly every year since its original discovery in 1886. Total gold production is approximately 500,000 troy ounces. Although many of the rich deposits have been mined, there still exist areas that contain gold. Areas of mined and unmined gold-bearing creek and terrace gravels are outlined on the accompanying geologic map.
The early history of the Fortymile area centered on the small frontier settlement of Fortymile City located at the junction of the Fortymile and Yukon Rivers in Canadian territory. This was the supply and jumping-off point for prospectors who worked their way into Alaska up the Fortymile River and found gold on many of its tributaries. Hand mining, both underground and surface, using sluice boxes and (or) rockers were the earliest methods; later, hydraulicking, dredging, and draglining methods were used. More recently, bulldozers and elevated trammels have been used, as well as very portable floating suction dredges. The rich mining lore of the area is closely associated with events of the nearby world-famous Klondike District. Bedrock and placer geology and mining history of individual gold-rich creeks are herein updated.
The Fortymile area, which is part of the Yukon-Tanana Upland, contains quartzite, schist, gneiss, amphibolite, marble, serpentinite, and granite overlain by basalt, sandstone, conglomerate, shale, tuff, and coal; overlying these rocks are several deposits of varying ages consisting of gold-bearing gravel and colluvium. The close spatial association of creeks containing placer gold and the gneiss, schist, amphibolite, and marble unit strongly suggests this metamorphic unit is the gold source.
High terrace gravels record a time from the late Tertiary to early Pleistocene when the ancestral Fortymile River and its major tributaries, the North and South Forks, had floodplains roughly 1 to 2 miles (2-3 kilometers) wide and gradients of about 4 feet per mile (0.75 meters per kilometer). Base-level lowering during the post-early Pleistocene caused the rivers to cut into their floodplains and to develop the youthful characteristics they have today such as V-shaped canyons, narrow floodplains, and gradients of at least twice those of the old river.
Colluvium marginal to creek deposits in steep-sided valleys is often gold bearing. Much of the unconsolidated gravel within the major drainages of the Fortymile River, South Fork, North Fork, and Mosquito Fork is colluvium.
Heavy-mineral-concentrate samples from the gold-producing creeks and high terrace gravels contain varying amounts of magnetite (20 to 80 percent) and ilmenite (10 to 30 percent), and samples from creeks draining areas principally composed of metamorphic rocks contain abundant garnet (10 to 30 percent). Gold fineness ranges from 620 to 927, but it is difficult to attach any geologic significance to the fineness data.
Most placer gold in the Fortymile River area has been recovered at, or near, the gravelbedrock contact. The lowermost 3.3 feet (1 meter) of gravel and the uppermost 1.6 feet (0.5 meter) of bedrock may contain as much as 80 to 90 percent of the gold that is ultimately recovered. Gold nuggets are rare and most of the gold recovered is in the form of flattened fragments less than .2 inches (5 millimeters) in greatest dimension. However, large gold nuggets have been found on Wade Creek; examples are ones of 25,33,56, and 70 ounces. Occasionally, large nuggets may still be found in the tailing piles along the creek.
The Fortymile River and its tributaries the South Fork, Walker Fork, and Mosquito Fork, all of which at one time were the sites of bucket-line dredge operations, now are almost exclusively mined using floating suction dredges. Unmined gold-bearing gravel is present in the floodplain of the Walker Fork valley below Cherry Creek and in low (about 100 to 130 feet or 30 to 40 meters) terraces along the north side of Walker Fork and east side of Cherry Creek. Considering the locations of where most gold has been found in the South Fork valley both by the older bucket dredges and the modern suction dredges, it seems likely that the tributary drainages of Lost Chicken, Napoleon, Franklin, and Buckskin Creeks have supplied the bulk of the gold to the South Fork valley. A quarter acre (0.10 hectare), 130-foot-thick ( 40 meters) section of the high terrace gravels on the north side of Napoleon Creek was mined for placer gold and yielded values estimated to be $8.50 per cubic yard (or $6.50 per cubic meter) at $350 per troy ounce. The unmined high terrace gravels on the south side of Buckskin Creek contain gold; however, this gravel is only 3 to 6.5 feet (1 to 2 meters) thick.
The search for a lode gold source in the Fortymile River region may be in vain, because substantially more gold than has been recovered from the placers can be derived by the gradual erosion of large volumes of source rocks that contain background mean gold amounts. Using Leon's mass balance equation, 5,167 metric tons of gold may exist in the placers of the Fortymile River region, less than 1 percent of the recovered amount of 15.6 tons.
The largest gold resource remaining in the Fortymile River region is probably in the high terrace gravels exposed along many of the creeks and rivers. Until there is exploratory drilling or a comprehensive sampling program, the amount of gold in these gravels will remain unknown. Environmental constraints imposed by Federal and State agencies have slowed, but not stopped, placer mining in the Fortymile River area, and a significant gold price rise would result in more mining.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/b2125","usgsCitation":"Yeend, W.E., 1996, Gold placers of the historical Fortymile River region, Alaska: U.S. Geological Survey Bulletin 2125, Report: 75 p.; Plate: 35.44 x 38.25 inches, https://doi.org/10.3133/b2125.","productDescription":"Report: 75 p.; Plate: 35.44 x 38.25 inches","costCenters":[],"links":[{"id":247657,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/bul/2125/report.pdf","text":"Report","size":"25.02 MB","linkFileType":{"id":1,"text":"pdf"},"description":"Report"},{"id":111160,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://www.dggs.dnr.state.ak.us/pubs/id/3781","linkFileType":{"id":5,"text":"html"}},{"id":247658,"rank":400,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/2125/plate-1.pdf","text":"Plate","size":"10.96 MB","linkFileType":{"id":1,"text":"pdf"},"description":"Plate"},{"id":252059,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/bul/2125/report-thumb.jpg"}],"country":"United States","state":"Alaska","otherGeospatial":"Fortymile River region","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -142.1,\n 64\n ],\n [\n -141,\n 64\n ],\n [\n -141,\n 64.5\n ],\n [\n -142.1,\n 64.5\n ],\n [\n -142.1,\n 64\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4abde4b07f02db6740b2","contributors":{"authors":[{"text":"Yeend, Warren E.","contributorId":65053,"corporation":false,"usgs":true,"family":"Yeend","given":"Warren","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":216129,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":24565,"text":"ofr96335 - 1996 - Location maps and list of U.S. Geological Survey reports on water resources in Alaska, 1950 to 1995","interactions":[],"lastModifiedDate":"2012-02-02T00:08:00","indexId":"ofr96335","displayToPublicDate":"1996-11-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":330,"text":"Open-File Report","code":"OFR","onlineIssn":"2331-1258","printIssn":"0196-1497","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"96-335","title":"Location maps and list of U.S. Geological Survey reports on water resources in Alaska, 1950 to 1995","docAbstract":"Reports written by U.S. Geological Survey members between 1950 through 1995 on the water resources of Alaska are listed. Location maps are given for six geographic areas: Arctic Slope, West, Southwest, East-central, Southcentral, and Southeast. Numbers on location maps refer to the bibliographic citations. Reports are also cited for the following categories: Statewide and Topical, Glaciers, and Trans-Alaska Pipeline System.","language":"ENGLISH","publisher":"U.S. Geological Survey ;\r\nBranch of Information Services [distributor],","doi":"10.3133/ofr96335","issn":"0094-9140","usgsCitation":"Snyder, E., 1996, Location maps and list of U.S. Geological Survey reports on water resources in Alaska, 1950 to 1995: U.S. Geological Survey Open-File Report 96-335, 48 p. :ill., maps ;28 cm., https://doi.org/10.3133/ofr96335.","productDescription":"48 p. :ill., maps ;28 cm.","costCenters":[],"links":[{"id":155061,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1996/0335/report-thumb.jpg"},{"id":53613,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1996/0335/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a69e4b07f02db63be55","contributors":{"authors":[{"text":"Snyder, E.F.","contributorId":18787,"corporation":false,"usgs":true,"family":"Snyder","given":"E.F.","email":"","affiliations":[],"preferred":false,"id":192165,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":31952,"text":"ofr9622 - 1996 - Geologic map of the Allentown East quadrangle, Lehigh, Northampton, and Bucks Counties, Pennsylvania","interactions":[],"lastModifiedDate":"2022-08-16T19:52:39.987166","indexId":"ofr9622","displayToPublicDate":"1996-11-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":330,"text":"Open-File Report","code":"OFR","onlineIssn":"2331-1258","printIssn":"0196-1497","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"96-22","title":"Geologic map of the Allentown East quadrangle, Lehigh, Northampton, and Bucks Counties, Pennsylvania","docAbstract":"No abstract available.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ofr9622","usgsCitation":"Drake, A.A., 1996, Geologic map of the Allentown East quadrangle, Lehigh, Northampton, and Bucks Counties, Pennsylvania: U.S. Geological Survey Open-File Report 96-22, Report: 27 p.; 1 Plate: 45.03 × 29.36 inches, https://doi.org/10.3133/ofr9622.","productDescription":"Report: 27 p.; 1 Plate: 45.03 × 29.36 inches","costCenters":[],"links":[{"id":60105,"rank":400,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/of/1996/0022/plate-1.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":60106,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1996/0022/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":397792,"rank":4,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_19361.htm","linkFileType":{"id":5,"text":"html"}},{"id":161136,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1996/0022/report-thumb.jpg"}],"scale":"24000","country":"United States","state":"Pennsylvania","county":"Bucks County, Lehigh County, Northampton County","otherGeospatial":"Allentown East quadrangle","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -75.5,\n 40.5\n ],\n [\n -75.375,\n 40.5\n ],\n [\n -75.375,\n 40.625\n ],\n [\n -75.5,\n 40.625\n ],\n [\n -75.5,\n 40.5\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b12e4b07f02db6a2571","contributors":{"authors":[{"text":"Drake, Avery A. Jr.","contributorId":81090,"corporation":false,"usgs":true,"family":"Drake","given":"Avery","suffix":"Jr.","middleInitial":"A.","affiliations":[],"preferred":false,"id":207336,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":1000786,"text":"1000786 - 1996 - Discrimination among spawning concentrations of Lake Superior lake herring based on trace element profiles in sagittae","interactions":[],"lastModifiedDate":"2026-03-25T15:59:59.384087","indexId":"1000786","displayToPublicDate":"1996-11-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3624,"text":"Transactions of the American Fisheries Society","active":true,"publicationSubtype":{"id":10}},"title":"Discrimination among spawning concentrations of Lake Superior lake herring based on trace element profiles in sagittae","docAbstract":"Little is known about the stock structure of lake herring Coregonus artedi in Lake Superior, and recent increases in harvestable stock sizes has led to expanded exploitation in some areas. Research on marine teleosts has demonstrated that chemical differences in sagittal otoliths can be used for identification of fish stocks. We used plasma emission spectrophotometry to measure the concentrations of 10 trace elements in the sagittal otoliths from lake herring captured at eight spawning sites in Lake Superior and from Little Star Lake. an inland lake outside the Lake Superior basin. Discriminant function analysis indicated that elemental concentrations provided site‐specific information but that considerable overlap existed among some locations, especially those in western Lake Superior. Correct classification rates varied from 12.0% to 86.1% and were generally higher for spawning locations from embayments in eastern Lake Superior and for the outgroup population from Little Star Lake. The results presented here demonstrate the potential usefulness of this technique for strictly freshwater species, especially those that live in highly oligotrophic waters such as Lake Superior.
","language":"English","publisher":"American Fisheries Society","doi":"10.1577/1548-8659(1996)125<0852:DASCOL>2.3.CO;2","usgsCitation":"Bronte, C.R., Hesselberg, R.J., Shoesmith, J.A., and Hoff, M.H., 1996, Discrimination among spawning concentrations of Lake Superior lake herring based on trace element profiles in sagittae: Transactions of the American Fisheries Society, v. 125, no. 6, p. 852-859, https://doi.org/10.1577/1548-8659(1996)125<0852:DASCOL>2.3.CO;2.","productDescription":"8 p.","startPage":"852","endPage":"859","costCenters":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"links":[{"id":133639,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Canada, United States","otherGeospatial":"Lake Superior, Little Star Lake","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -92.64404051195237,\n 49.322654990120384\n ],\n [\n -92.64404051195237,\n 46.28314472135693\n ],\n [\n -84.29015043122145,\n 46.28314472135693\n ],\n [\n -84.29015043122145,\n 49.322654990120384\n ],\n [\n -92.64404051195237,\n 49.322654990120384\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"125","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a82e4b07f02db64acae","contributors":{"authors":[{"text":"Bronte, Charles R.","contributorId":83050,"corporation":false,"usgs":true,"family":"Bronte","given":"Charles","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":309430,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hesselberg, Robert J.","contributorId":36074,"corporation":false,"usgs":true,"family":"Hesselberg","given":"Robert","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":309429,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Shoesmith, John A.","contributorId":7653,"corporation":false,"usgs":true,"family":"Shoesmith","given":"John","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":309427,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hoff, Michael H.","contributorId":23878,"corporation":false,"usgs":true,"family":"Hoff","given":"Michael","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":309428,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":68468,"text":"ha694D - 1996 - Hydrogeology of structurally extended terrain in the eastern Great Basin of Nevada, Utah, and adjacent states, from geologic and geophysical models","interactions":[],"lastModifiedDate":"2015-10-28T11:24:22","indexId":"ha694D","displayToPublicDate":"1996-11-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":318,"text":"Hydrologic Atlas","code":"HA","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"694","chapter":"D","title":"Hydrogeology of structurally extended terrain in the eastern Great Basin of Nevada, Utah, and adjacent states, from geologic and geophysical models","docAbstract":"The Great Basin of the western United States encompasses most of Nevada and western Utah (fig. 1). The climate of the region is semiarid to arid, with most precipitation falling as winter Show. The region is characterized by internal drainage (generally no hydrologic outlet to the ocean). Water resources in the region are limited and nearly all reliable surface-water sources have been allocated for use. The most commonly used aquifers arc sand-and-gravel basin-fill deposits in structural basins of the region. In many basins, pumpage from the basin-fill aquifers is as much as (or more than) the safe yield.
Consequently, aquifers other than basin fill are being assessed in the eastern Great Basin to determine where and how much additional ground water is present and what might be the effects of development. This study was part of the Nevada Carbonate Aquifers Program, in cooperation with the State of Nevada, Las Vegas Valley Water District, City of North Las Vegas, and the Bureau of Reclamation. This atlas presents a conceptual model of the geologic and hydrologic features of structurally extended terrains in the eastern Great Basin. First, the model is described and major structural features are compared with regional groundwater flow patterns. Second, the validity of the conceptual hydrogeologic model is evaluated using geophysical data and geologic models derived from geophysical profiles.
The terrace alluvial aquifer underlying Air Force Plant 4 and the adjacent Naval Air Station (formerly Carswell Air Force Base) in the Fort Worth area, Texas, is contaminated locally with organic and metal compounds. Residents south and west of Air Force Plant 4 and the Naval Air Station are concerned that contaminants might enter the underlying Paluxy aquifer, which provides water to the city of White Settlement, south of Air Force Plant 4, and to residents west of Air Force Plant 4. The U.S. Environmental Protection Agency has qualified Air Force Plant 4 for Superfund cleanup.
The pertinent geologic units include -A~rom oldest to youngest the Glen Rose, Paluxy, and Walnut Formations, Goodland Limestone, and terrace alluvial deposits. Except for the Glen Rose Formation, all units crop out at or near Air Force Plant 4 and the Naval Air Station. The terrace alluvial deposits, which nearly everywhere form the land surface, range from 0 to about 60 feet thick. These deposits comprise a mostly unconsolidated mixture of gravel, sand, silt, and clay. Mudstone and sandstone of the Paluxy Formation crop out north, west, and southwest of Lake Worth and total between about 130 and about 175 feet thick.
The terrace alluvial deposits and the Paluxy Formation comprise the terrace alluvial aquifer and the Paluxy aquifer, respectively. These aquifers are separated by the Goodland-Walnut confining unit, composed of the Goodland Limestone and (or) Walnut Formation. Below the Paluxy aquifer, the Glen Rose Formation forms the Glen Rose confining unit.
Water-level measurements during May 1993 and February 1994 from wells in the terrace alluvial aquifer indicate that, regionally, ground water flows toward the east-southeast beneath Air Force Plant 4 and the Naval Air Station. Locally, water appears to flow outward from ground-water mounds maintained by the localized infiltration of precipitation and reportedly by leaking water pipes and sanitary and (or) storm sewer lines beneath the assembly building at Air Force Plant 4. North of Farmers Branch, the terrace alluvial aquifer discharges into Lake Worth, Meandering Road Creek, Farmers Branch, and the West Fork Trinity River. South of Farmers Branch, ground water appears to flow mostly north-northeastward. Greater precipitation prior to the May 1993 measurements caused water levels to average approximately 5 ft higher in May 1993 than in February 1994.
Regional ground-water gradients indicate west to east-southeastward flow in the Paluxy aquifer, with a dominant southeastward component beneath Air Force Plant 4. Water-level maps for the Paluxy \"upper sand\" reveal an elongated groundwater mound beneath southeastern parts of Air Force Plant 4, which indicates a localized, vertical conduit through which contaminated water from the terrace alluvial aquifer might enter upper parts of the Paluxy aquifer. The Paluxy \"upper sand\" apparently is mostly unsaturated and hydraulically separated from the deeper, regionally extensive parts of the Paluxy aquifer, most of which are fully saturated. While water levels in the \"upper sand\" were as much as 10 ft higher in May 1993 than in February 1994, water levels in most deeper parts of the Paluxy aquifer were slightly higher in February 1994 than they were in May 1993.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Austin, TX","doi":"10.3133/wri964032","collaboration":"Prepared in cooperation with the U.S. Air Force Aeronautical Systems Center, Environmental Management Directorate","usgsCitation":"Rivers, G.A., Baker, E.T., and Coplin, L., 1996, Geohydrologic units and water-level conditions in the Terrace alluvial aquifer and Paluxy Aquifer, May 1993 and February 1994, near Air Force Plant 4, Fort Worth area, Texas: U.S. Geological Survey Water-Resources Investigations Report 96-4032, Document: iv, 13 p.; 6 Plates: 28.99 x 28.02 inches or smaller, https://doi.org/10.3133/wri964032.","productDescription":"Document: iv, 13 p.; 6 Plates: 28.99 x 28.02 inches or smaller","costCenters":[{"id":583,"text":"Texas Water Science Center","active":true,"usgs":true}],"links":[{"id":99334,"rank":400,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/wri/1996/4032/plate-1.pdf","size":"2339","linkFileType":{"id":1,"text":"pdf"}},{"id":99335,"rank":401,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/wri/1996/4032/plate-2.pdf","size":"1449","linkFileType":{"id":1,"text":"pdf"}},{"id":99336,"rank":402,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/wri/1996/4032/plate-3.pdf","size":"2137","linkFileType":{"id":1,"text":"pdf"}},{"id":120386,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1996/4032/report-thumb.jpg"},{"id":99337,"rank":403,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/wri/1996/4032/plate-4.pdf","size":"2335","linkFileType":{"id":1,"text":"pdf"}},{"id":99338,"rank":404,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/wri/1996/4032/plate-5.pdf","size":"1546","linkFileType":{"id":1,"text":"pdf"}},{"id":99339,"rank":405,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/wri/1996/4032/plate-6.pdf","size":"1582","linkFileType":{"id":1,"text":"pdf"}},{"id":82227,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1996/4032/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"country":"United States","state":"Texas","city":"Fort Worth","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b1be4b07f02db6a8dd1","contributors":{"authors":[{"text":"Rivers, Glen A.","contributorId":91154,"corporation":false,"usgs":true,"family":"Rivers","given":"Glen","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":230578,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Baker, Ernest T. Jr.","contributorId":30263,"corporation":false,"usgs":true,"family":"Baker","given":"Ernest","suffix":"Jr.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":230576,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Coplin, L.S.","contributorId":49366,"corporation":false,"usgs":true,"family":"Coplin","given":"L.S.","affiliations":[],"preferred":false,"id":230577,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":5223443,"text":"5223443 - 1996 - Survival and recovery rates of American eiders in eastern North America","interactions":[],"lastModifiedDate":"2024-12-30T17:09:34.777938","indexId":"5223443","displayToPublicDate":"1996-10-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2508,"text":"Journal of Wildlife Management","active":true,"publicationSubtype":{"id":10}},"title":"Survival and recovery rates of American eiders in eastern North America","docAbstract":"We analyzed banding and recovery data of adult female American eiders (Somateria mollissima dresseri) captured during the breeding season in eastern North America. We estimated survival rates for birds originating in the Atlantic Coast subpopulation to be 0.8730 ± 0.0156 (SE) while recovery rates were 0.0101 ± 0.0080 (SE). Support for several banding reference areas of American eiders was found. No trends were detected in band recovery, harvest rates or harvest over time.
","language":"English","publisher":"Wiley","doi":"10.2307/3802386","usgsCitation":"Krementz, D.G., Hines, J., and Caithamer, D.F., 1996, Survival and recovery rates of American eiders in eastern North America: Journal of Wildlife Management, v. 60, no. 4, p. 855-862, https://doi.org/10.2307/3802386.","productDescription":"8 p.","startPage":"855","endPage":"862","costCenters":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":199977,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Canada, United States","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -55.74027412555816,\n 54.25213694082302\n ],\n [\n -60.11823463194552,\n 50.84403243570601\n ],\n [\n -66.26875859046969,\n 51.003422676813166\n ],\n [\n -70.84195216691883,\n 47.410269531254215\n ],\n [\n -64.80467629944273,\n 49.24640460840743\n ],\n [\n -64.8816390987326,\n 46.25167814028854\n ],\n [\n -70.09576391067104,\n 44.346168926962505\n ],\n [\n -72.52800226852422,\n 41.06271081580675\n ],\n [\n -70.0811124859758,\n 41.32916448987016\n ],\n [\n -69.71362352202352,\n 43.15814815295754\n ],\n [\n -67.6664417782555,\n 43.798634128861245\n ],\n [\n -66.00530842173055,\n 43.14542945900638\n ],\n [\n -63.58876648292551,\n 43.82125927596849\n ],\n [\n -51.95473254250956,\n 46.760307170871855\n ],\n [\n -55.74027412555816,\n 54.25213694082302\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"60","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ae2e4b07f02db688e51","contributors":{"authors":[{"text":"Krementz, David G. 0000-0002-5661-4541 dkrementz@usgs.gov","orcid":"https://orcid.org/0000-0002-5661-4541","contributorId":2827,"corporation":false,"usgs":true,"family":"Krementz","given":"David","email":"dkrementz@usgs.gov","middleInitial":"G.","affiliations":[{"id":198,"text":"Coop Res Unit Atlanta","active":true,"usgs":true}],"preferred":true,"id":338764,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hines, James E. jhines@usgs.gov","contributorId":3506,"corporation":false,"usgs":true,"family":"Hines","given":"James E.","email":"jhines@usgs.gov","affiliations":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"preferred":false,"id":338763,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Caithamer, David F.","contributorId":24888,"corporation":false,"usgs":true,"family":"Caithamer","given":"David","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":338762,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":5085,"text":"fs12396 - 1996 - South Florida Ecosystem Program: Quantifying freshwater discharge for coastal hydraulic control structures in eastern Dade County, Florida","interactions":[],"lastModifiedDate":"2021-12-02T16:02:22.173541","indexId":"fs12396","displayToPublicDate":"1996-10-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":313,"text":"Fact Sheet","code":"FS","onlineIssn":"2327-6932","printIssn":"2327-6916","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"123-96","displayTitle":"South Florida Ecosystem Program: Quantifying Freshwater Discharge for Coastal Hydraulic Control Structures in Eastern Dade County, Florida","title":"South Florida Ecosystem Program: Quantifying freshwater discharge for coastal hydraulic control structures in eastern Dade County, Florida","docAbstract":"The South Florida Ecosystem Restoration Program is an intergovernmental effort, involving a number of agencies, to reestablish and maintain the ecosystem of south Florida. One element of the restoration effort is the development of a firm scientific basis for resource decision making. The U.S. Geological Survey (USGS), one of the agencies, provides scientific information as part of the South Florida Ecosystem Restoration Program. The USGS began their ow program, called the South Florida Ecosystem Program, in fiscal year 1995 for the purpose of gathering hydrologic, cartographic, and geologic data that relate to the mainland of south Florida, Florida Bay, and the Florida Keys and Reef ecosystems.
As part of the South Florida Ecosystem Program, the USGS, in cooperation with the South Florida Water Management District (SFWMD), has conducted a study to determine discharge ratings for 16 coastal hydraulic control structures in eastern Dade County, Fla. Discharge data are needed to quantify water that can be made available for water supply and ecosystem restoration and to calibrate regional hydrologic models.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/fs12396","usgsCitation":"Kapadia, A., and Swain, E.D., 1996, South Florida Ecosystem Program: Quantifying freshwater discharge for coastal hydraulic control structures in eastern Dade County, Florida: U.S. Geological Survey Fact Sheet 123-96, 4 p., https://doi.org/10.3133/fs12396.","productDescription":"4 p.","numberOfPages":"4","costCenters":[{"id":27821,"text":"Caribbean-Florida Water Science Center","active":true,"usgs":true}],"links":[{"id":139766,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/fs12396.jpg"},{"id":285404,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/fs/0123-96/report.pdf","text":"Report","size":"1.79 MB","linkFileType":{"id":1,"text":"pdf"},"description":"FS 1996-123"}],"country":"United States","state":"Florida","county":"Dade County","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -80.7503,25.0989 ], [ -80.7503,25.9794 ], [ -80.063,25.9794 ], [ -80.063,25.0989 ], [ -80.7503,25.0989 ] ] ] } } ] }","contact":"Caribbean-Florida Water Science Center
U.S. Geological Survey
3321 College Avenue
Davie, FL 33314
Among the duties of the water managers of the Leech Lake Indian Reservation in north-central Minnesota are the development and protection of the water resources of the Reservation. The U.S. Geological Survey, in cooperation with the Leech Lake Indian Reservation Business Committee, conducted a three and one half-year study (1988-91) of the ground-water resources of the Leech Lake Indian Reservation. The objectives of this study were to describe the availability and quality of ground water contained in glacial-drift aquifers underlying the Reservation.
Aquifers and confining units are present throughout the entire thickness of the glacial drift in the study area, which includes the Leech Lake Indian Reservation and adjacent parts of Beltrami, Hubbard, Itasca, and Cass Counties in north-central Minnesota, an area of approximately 2,145 square miles. An unconfined aquifer underlies most of the central and north-central parts of the study area. The saturated thickness of the aquifer ranges from 0 to about 105 feet. Horizontal hydraulic conductivity, estimated from 19 slug tests, ranges from 0.6 to 31 feet per day. The transmissivity of the aquifer ranges from 19 to more than 20,000 feet squared per day and is greatest in an area from west of Cass Lake to Lake Winnibigoshish. Theoretical maximum well yields range from less than 10 to about 2,000 gallons per minute. The unconfined and uppermost confined aquifers are physically and hydraulically separated by a fine-grained confining unit, consisting of till or lake deposits, that ranges in thickness from 3 to 254 feet.
The thickness of the uppermost confined aquifer ranges from 5 to about 53 feet. On the basis of specific-capacity data, the transmissivity of the aquifer ranges from less than 100 feet squared per day in the northeastern and southeastern parts of the study area to about 21,000 feet squared per day near Cass Lake. Theoretical maximum well yields range from less than 10 to about 2,600 gallons per minute.
Recharge to the ground-water system is predominantly from precipitation that infiltrates to the saturated zone. An analysis of four hydrographs for observation wells screened in the unconfined aquifer indicated spring recharge amounts during 1989 of 1-4 inches.
Discharge from the ground-water system occurs by leakage to streams, lakes, and wetlands, evapotranspiration, withdrawals by wells, and underflow to the southeast within the Mississippi River Valley. Streamflow measurements indicate that ground-water discharge to the Mississippi River is greater in the western part of the study area between Cass Lake and Lake Winnibigoshish than in the eastern part downstream from Lake Winnibigoshish.
The general regional direction of ground-water flow in the unconfined and uppermost confined aquifers is to the east and southeast. Ground-water flow is also toward the Mississippi River and the three large lakes in the study area, Lake Winnibigoshish and Cass and Leech Lakes.
Water moves through the ground-water system predominantly horizontally in the aquifers, whereas vertical components of flow are significant in confining units. Downward leakage of water occurs in highland areas where ground water flows downward from overlying till to the uppermost confined aquifer. Water moves vertically upward from deep to shallow aquifers in areas of regional discharge, the Mississippi River, Cass Lake, Lake Winnibigoshish. and Leech Lake.
Waters from both the unconfined and uppermost confined aquifers generally are suitable for domestic consumption, crop irrigation, and most other uses. Concentrations of iron and manganese in water from both aquifers frequently exceed levels that may impart an undesirable taste or odor to water.
Calcium and bicarbonate are the predominant ions in water from both the unconfined and uppermost confined aquifers. Water from both the unconfined and uppermost confined aquifers is hard to very hard, averaging 187 and 247 milligrams per liter as calcium carbonate, respectively.
Differences in the mean concentrations of constituents in waters from the unconfined and uppermost confined aquifers vary. The mean concentrations of chloride, manganese, dissolved organic carbon, sulfate, and dissolved iron were greater for water from the unconfined aquifer than for water from the uppermost confined aquifer. Conversely, the mean concentrations of calcium, potassium, silica, sodium, fluoride, and boron were greater for water from the uppermost confined aquifer than for water from the unconfined aquifer. These higher concentrations of naturally occurring constituents in waters from the uppermost confined aquifer may occur because of the longer flow paths and longer residence times of water in the uppermost confined aquifer as compared to the unconfined aquifer.
Nutrients include nitrogen and phosphorus species. The mean concentrations of dissolved nitrogen (NO2 + NO3, dissolved) and total phosphorus were about 5 and 1.5 times greater for water from the unconfined aquifer than for water from the uppermost confined aquifer, respectively. None of the water samples had concentrations of dissolved nitrogen greater than the maximum contaminant level established by the U.S. Environmental Protection Agency (10 milligrams per liter) and only one water sample had a concentration greater than 3 milligrams per liter.
Water collected from wells completed in the unconfined aquifer in residential and recreational land-use areas had concentrations of arsenic, cadmium, chromium, copper, lead, mercury, and cyanide equal to or less than 6 micrograms per liter. Concentrations of organic-acid herbicides in water from three wells screened in the unconfined aquifer in managed-forest land-use areas were all below detection levels. Concentrations of U.S. Environmental Protection Agency priority pollutants in water from three wells screened in the unconfined aquifer and from one well screened in the uppermost confined aquifer were also all below detection levels.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Mounds View, MN","doi":"10.3133/wri954077","collaboration":"Prepared in cooperation with the Leech Lake Indian Reservation Business Committee","usgsCitation":"Lindgren, R.J., 1996, Hydrogeology and ground-water quality of glacial-drift aquifers, Leech Lake Indian Reservation, north-central Minnesota: U.S. Geological Survey Water-Resources Investigations Report 95-4077, viii, 78 p., https://doi.org/10.3133/wri954077.","productDescription":"viii, 78 p.","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":392,"text":"Minnesota Water Science Center","active":true,"usgs":true}],"links":[{"id":415725,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_48186.htm","linkFileType":{"id":5,"text":"html"}},{"id":57180,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1995/4077/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":121738,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1995/4077/report-thumb.jpg"}],"country":"United States","state":"Minnesota","otherGeospatial":"Leech Lake Indian Reservation","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -94.8,\n 47.666667\n ],\n [\n -93.7,\n 47.666667\n ],\n [\n -93.7,\n 47.2\n ],\n [\n -94.1,\n 47.2\n ],\n [\n -94.1,\n 47\n ],\n [\n -94.8,\n 47\n ],\n [\n -94.8,\n 47.666667\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a4be4b07f02db62567f","contributors":{"authors":[{"text":"Lindgren, R. J.","contributorId":70808,"corporation":false,"usgs":true,"family":"Lindgren","given":"R.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":199696,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":21979,"text":"ofr9620B - 1996 - Neogene and Quaternary geology of a stratigraphic test hole on Horn Island, Mississippi Sound","interactions":[],"lastModifiedDate":"2020-03-27T06:59:20","indexId":"ofr9620B","displayToPublicDate":"1996-09-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":330,"text":"Open-File Report","code":"OFR","onlineIssn":"2331-1258","printIssn":"0196-1497","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"96-20","chapter":"B","title":"Neogene and Quaternary geology of a stratigraphic test hole on Horn Island, Mississippi Sound","docAbstract":"No abstract available.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ofr9620B","issn":"0094-9140","usgsCitation":"Gohn, G., Brewster-Wingard, G., Cronin, T.M., Edwards, L.E., Gibson, T., Rubin, M., and Willard, D., 1996, Neogene and Quaternary geology of a stratigraphic test hole on Horn Island, Mississippi Sound: U.S. Geological Survey Open-File Report 96-20, 23 p., https://doi.org/10.3133/ofr9620B.","productDescription":"23 p.","costCenters":[{"id":243,"text":"Eastern Geology and Paleoclimate Science Center","active":true,"usgs":true},{"id":40020,"text":"Florence Bascom Geoscience Center","active":true,"usgs":true}],"links":[{"id":51453,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1996/0020b/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":152930,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1996/0020b/report-thumb.jpg"}],"country":"United States","state":"Mississippi, Alabama ","otherGeospatial":"Mississippi Sound","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -88.78910064697266,\n 30.208937975696163\n ],\n [\n -88.57315063476562,\n 30.208937975696163\n ],\n [\n -88.57315063476562,\n 30.267370168467806\n ],\n [\n -88.78910064697266,\n 30.267370168467806\n ],\n [\n -88.78910064697266,\n 30.208937975696163\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4affe4b07f02db697e2f","contributors":{"authors":[{"text":"Gohn, Gregory 0000-0003-2000-479X ggohn@usgs.gov","orcid":"https://orcid.org/0000-0003-2000-479X","contributorId":219822,"corporation":false,"usgs":true,"family":"Gohn","given":"Gregory","email":"ggohn@usgs.gov","affiliations":[{"id":243,"text":"Eastern Geology and Paleoclimate Science Center","active":true,"usgs":true},{"id":40020,"text":"Florence Bascom Geoscience Center","active":true,"usgs":true}],"preferred":true,"id":186531,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Brewster-Wingard, G. L.","contributorId":102508,"corporation":false,"usgs":true,"family":"Brewster-Wingard","given":"G. L.","affiliations":[],"preferred":false,"id":186533,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Cronin, Thomas M. 0000-0002-2643-0979 tcronin@usgs.gov","orcid":"https://orcid.org/0000-0002-2643-0979","contributorId":2579,"corporation":false,"usgs":true,"family":"Cronin","given":"Thomas","email":"tcronin@usgs.gov","middleInitial":"M.","affiliations":[{"id":40020,"text":"Florence Bascom Geoscience Center","active":true,"usgs":true},{"id":243,"text":"Eastern Geology and Paleoclimate Science Center","active":true,"usgs":true}],"preferred":true,"id":186530,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Edwards, Lucy E. 0000-0003-4075-3317 leedward@usgs.gov","orcid":"https://orcid.org/0000-0003-4075-3317","contributorId":2647,"corporation":false,"usgs":true,"family":"Edwards","given":"Lucy","email":"leedward@usgs.gov","middleInitial":"E.","affiliations":[{"id":243,"text":"Eastern Geology and Paleoclimate Science Center","active":true,"usgs":true},{"id":40020,"text":"Florence Bascom Geoscience Center","active":true,"usgs":true}],"preferred":true,"id":186529,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Gibson, T. G.","contributorId":103702,"corporation":false,"usgs":true,"family":"Gibson","given":"T. G.","affiliations":[],"preferred":false,"id":186534,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Rubin, Meyer","contributorId":107283,"corporation":false,"usgs":true,"family":"Rubin","given":"Meyer","email":"","affiliations":[],"preferred":false,"id":186535,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Willard, Debra A. 0000-0003-4878-0942","orcid":"https://orcid.org/0000-0003-4878-0942","contributorId":85982,"corporation":false,"usgs":true,"family":"Willard","given":"Debra A.","affiliations":[],"preferred":false,"id":186532,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":25829,"text":"wri954203 - 1996 - Water-quality assessment of the Connecticut, Housatonic, and Thames River Basins study unit: Analysis of available data on nutrients, suspended sediments, and pesticides, 1972-92","interactions":[],"lastModifiedDate":"2021-12-27T21:04:56.036888","indexId":"wri954203","displayToPublicDate":"1996-09-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"95-4203","title":"Water-quality assessment of the Connecticut, Housatonic, and Thames River Basins study unit: Analysis of available data on nutrients, suspended sediments, and pesticides, 1972-92","docAbstract":"This retrospective report examines available nutrient, suspended sediment, and pesticide data in surface and ground water in the Connecticut, Housatonic and Thames Rivers Study Unit of the National Water-Quality Assessment Program. The purpose of this study is to improve the understanding of natural and anthropogenic factors affecting water quality in the study unit. Waterquality data were acquired from various sources, primarily, the U.S. Geological Survey and the U.S. Environmental Protection Agency. The report examines data for water years 1972-92, focusing on 1980-92, although it also includes additional data from as early as 1905.
The study unit lies within the New England Physiographic Province and altitudes range from sea level in coastal Connecticut to 6,288 feet above sea level at Mount Washington, New Hampshire. Two major aquifer types underlie the study unit unconsolidated glacial deposits and fractured bedrock. The climate generally is temperate and humid, with four distinct seasons. Average annual precipitation ranges from 34 to 65 inches. The study unit has a population of about 4.5 million, which is most highly concentrated in southwestern Connecticut and along the south-central region of the Connecticut River Valley.
Surface-water-quality data were screened to provide information about sites with adequate numbers of analyses (50) over sufficiently long periods (1980-90) to enable valid statistical analyses. In order to compare effects of different types of land use on surface-water quality, examination of data required application of several statistical and graphical techniques, including mapping, histograms, boxplots, concentration-discharge plots, trend analysis, and load estimation. Spatial and temporal analysis of surface-water-quality data indicated that, with a single exception, only stations in the Connecticut water-quality network had sufficient data collected over adequately long time periods to use in detailed analyses.
Ground-water nutrient and pesticide data were compiled from several Federal and State agencies, primarily the U.S. Geological Survey, U.S. Environmental Protection Agency, and Connecticut Department of Health Services. Nutrient data were available for several thousand wells; nitrite plus nitrate as nitrogen was the most commonly reported constituent. Most wells with nutrient data are in Massachusetts and Connecticut.
Relative to nutrient data in ground and surface water, pesticide data are less common. Pesticide data were available for slightly more than 200 surface-water sites and less than 500 wells; about 95 percent of the wells are completed in stratified-drift or till aquifers. Data for 81 pesticide compounds were available in various data bases. 2,4-D and silvex were the most commonly detected herbicides in surface water and dieldrin and diazinon were the most commonly detected insecticides. Most surface-water pesticide samples and detections are from bed sediment, but much of the data are not recent.
Ethylene dibromide (EDB), a soil fumigant used in tobacco farming was detected in 268 wells in a 50 square-mile area of north-central Connecticut; EDB contamination also was detected in wells in Massachusetts. Atrazine, an herbicide commonly used in corn farming, commonly was detected in wells installed in tilled agricultural fields. Corn herbicides were commonly detected in the northern part of the study unit, although the sampling has been less frequent than in the southern part of the study unit. Pesticides were seldom detected in public-supply wells in Connecticut.
Urban sites with relatively high population densities and high concentrations of dischargers were characterized by having the highest nutrient concentrations and loads when adjusted for differences in drainage area or population. Particularly, the Pequabuck, Naugatuck, and Quinnipiac River Basins were characterized by high nutrient concentrations median total nitrogen concentrations ranged from 3.3 to 4.2 mg/L (milligrams per liter) and median total phosphorus concentrations ranged from 0.42 to 0.8 mg/L. In contrast, the predominantly forested and low density residential land-use sites, such as Saugatuck and Salmon River Basins, were characterized by low nutrient concentrations median total nitrogen ranged from 0.50 to 0.60 mg/L and median total phosphorus concentrations ranged from 0.01 to 0.02 mg/L. Estimated total nitrogen loadings in median discharge years ranged from 940 kilograms per square mile at the Salmon River near East Hampton, Conn., to 5,800 kilograms per square mile at the Naugatuck River at Beacon Falls, Conn. Water quality, in terms of nutrient concentrations and areally adjusted loadings, for sites with large drainage basins integrating a wide variety of land-use categories fell between the extremes of the urban and forested sites total nitrogen was 1,400 kilograms per square mile per year at the Connecticut River at Thompsonville, Conn.
Nitrate concentrations in ground water occasionally exceeded the safe drinking-water standard of 10 mg/L as nitrogen. The greatest number of detections exceeding the standard, however, were not in public-water supplies but in shallow observation wells in agricultural settings (the most frequently sampled type of well). None of the public-supply wells in Massachusetts exceeded the standard. Although nitrate concentrations for Vermont and New Hampshire generally were low, few data were available and those were seldom reported on the basis of drainage basin, making analysis difficult.
Trend analysis indicated that flow-adjusted concentrations of total and dissolved phosphorus generally decreased during the period of analysis, however, total nitrogen did not change substantially. Decreases in ammonia concentrations with time were usually accompanied by increases in nitrate, suggesting improvements in sewage treatment.
The lack of adequate data from more or less exclusively agricultural areas points to the need for further study of the effects of fanning on surface-water quality in the study unit. Furthermore, additional information is needed on the rates, transformations, and movements of nutrients and other materials through and between the aquatic and terrestrial components of the study unit.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/wri954203","usgsCitation":"Zimmerman, M.J., Grady, S.J., Trench, E.C., Flanagan, S.M., and Nielson, M.G., 1996, Water-quality assessment of the Connecticut, Housatonic, and Thames River Basins study unit: Analysis of available data on nutrients, suspended sediments, and pesticides, 1972-92: U.S. Geological Survey Water-Resources Investigations Report 95-4203, Report: x, 162 p.; 1 Plate: 35.00 x 43.81 inches, https://doi.org/10.3133/wri954203.","productDescription":"Report: x, 162 p.; 1 Plate: 35.00 x 43.81 inches","costCenters":[],"links":[{"id":393471,"rank":4,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_48290.htm"},{"id":358782,"rank":3,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/wri/1995/4203/plate-1.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":54577,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1995/4203/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":119120,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1995/4203/report-thumb.jpg"}],"country":"Canada, United States","state":"Connecticut, Massachusetts, New Hampshire, Quebec, Rhode Island, Vermont","otherGeospatial":"Connecticut River Basin, Housatonic River Basin, Thames River Basin","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -74,\n 41\n ],\n [\n -70,\n 41\n ],\n [\n -70,\n 45.25\n ],\n [\n -74,\n 45.25\n ],\n [\n -74,\n 41\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49e5e4b07f02db5e7121","contributors":{"authors":[{"text":"Zimmerman, Marc J. mzimmerm@usgs.gov","contributorId":3245,"corporation":false,"usgs":true,"family":"Zimmerman","given":"Marc","email":"mzimmerm@usgs.gov","middleInitial":"J.","affiliations":[{"id":376,"text":"Massachusetts Water Science Center","active":true,"usgs":true}],"preferred":true,"id":195250,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Grady, Stephen J.","contributorId":101636,"corporation":false,"usgs":true,"family":"Grady","given":"Stephen","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":195248,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Trench, Elaine C. Todd etrench@usgs.gov","contributorId":4557,"corporation":false,"usgs":true,"family":"Trench","given":"Elaine","email":"etrench@usgs.gov","middleInitial":"C. Todd","affiliations":[],"preferred":true,"id":195247,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Flanagan, Sarah M. sflanaga@usgs.gov","contributorId":2666,"corporation":false,"usgs":true,"family":"Flanagan","given":"Sarah","email":"sflanaga@usgs.gov","middleInitial":"M.","affiliations":[{"id":466,"text":"New England Water Science Center","active":true,"usgs":true}],"preferred":false,"id":195246,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Nielson, Martha G.","contributorId":210067,"corporation":false,"usgs":true,"family":"Nielson","given":"Martha","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":195249,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":22021,"text":"ofr9642 - 1996 - Possible continuous-type (unconventional) gas accumulation in the Lower Silurian \"Clinton\" sands, Medina Group and Tuscarora Sandstone in the Appalachian Basin; a progress report of the 1995 project activities","interactions":[],"lastModifiedDate":"2012-02-02T00:07:45","indexId":"ofr9642","displayToPublicDate":"1996-09-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":330,"text":"Open-File Report","code":"OFR","onlineIssn":"2331-1258","printIssn":"0196-1497","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"96-42","title":"Possible continuous-type (unconventional) gas accumulation in the Lower Silurian \"Clinton\" sands, Medina Group and Tuscarora Sandstone in the Appalachian Basin; a progress report of the 1995 project activities","docAbstract":"INTRODUCTION: \r\nIn the U.S. Geological Survey's (USGS) 1995 National Assessment of United States oil and gas resources (Gautier and others, 1995), the Appalachian basin was estimated to have, at a mean value, about 61 trillion cubic feet (TCF) of recoverable gas in sandstone and shale reservoirs of Paleozoic age. Approximately one-half of this gas resource is estimated to reside in a regionally extensive, continuous-type gas accumulation whose reservoirs consist of low-permeability sandstone of the Lower Silurian 'Clinton' sands and Medina Group (Gautier and others, 1995; Ryder, 1995). Recognizing the importance of this large regional gas accumulation for future energy considerations, the USGS initiated in January 1995 a multi-year study to evaluate the nature, distribution, and origin of natural gas in the 'Clinton' sands, Medina Group sandstones, and equivalent Tuscarora Sandstone. The project is part of a larger natural gas project, Continuous Gas Accumulations in Sandstones and Carbonates, coordinated in FY1995 by Ben E. Law and Jennie L. Ridgley, USGS, Denver. Approximately 2.6 man years were devoted to the Clinton/Medina project in FY1995.\r\n\r\nA continuous-type gas accumulation, referred to in the project, is a new term introduced by Schmoker (1995a) to identify those natural gas accumulations whose reservoirs are charged throughout with gas over a large area and whose entrapment does not involve a downdip gas-water contact. Gas in these accumulations is located downdip of the water column and, thus, is the reverse of conventional-type hydrocarbon accumulations. Commonly used industry terms that are more or less synonymous with continuous-type gas accumulations include basin- centered gas accumulation (Rose and others, 1984; Law and Spencer, 1993), tight (low-permeability) gas reservoir (Spencer, 1989; Law and others, 1989; Perry, 1994), and deep basin gas (Masters, 1979, 1984).\r\n\r\nThe realization that undiscovered gas in Lower Silurian sandstone reservoirs of the Appalachian basin probably occurs in a continuous accumulation rather than in conventionally trapped, discrete accumulations represents a significant departure from the 1989 National Assessment (Mast and others, 1989; deWitt, 1993). In 1989, a direct assessment (field-size distributions required for play analysis were unavailable) of the Lower Silurian sandstone play gave, at a mean value, about 1.7 TCF of gas. The 1995 estimate (~30 TCF of gas) is so much greater than the 1989 estimate (~1.7 TCF of gas) because of the interpreted continuous nature of the accumulation and the assessment methodology applied. The methodology for continuous hydrocarbon accumulations assumes that the reservoirs in the accumulation are gas-saturated and takes into account: 1) estimated ultimate recovery (EUR) per well probability distributions, 2) optimum area that a well can drain (spacing), 3) number of untested drill sites having the appropriate spacing area, 4) success ratio of previously drilled holes, and 5) risk (Schmoker, 1995b).\r\n\r\nDavis (1984), Zagorski (1988, 1991), and Law and Spencer (1993) were among the first petroleum geologists to suggest that gas in the 'Clinton' sands and Medina Group sandstones was trapped in a basin-centered/deep basin accumulation. They recognized many of the earmarks of a basin-centered/deep basin accumulation such as low-permeability reservoirs, abnormally low formation pressure, coalesced gas fields, gas shows or production in most holes drilled, low water yields, and a general lack of structural control on entrapment. Ryder (1995) adopted this interpretation by defining four continuous-type gas plays (6728-6731) in the 'Clinton' sands-Medina Group interval (fig.1).\r\n\r\nPlay 6728 (Clinton/Medina sandstone gas high potential) covers a 17,000 sq mi region of western New York, northwestern Pennsylvania, eastern Ohio, and a small part of westernmost West Virginia that is very favorable for future gas resources (fig.1). Also, this play includes a l","language":"ENGLISH","publisher":"U.S. Geological Survey,","doi":"10.3133/ofr9642","issn":"0094-9140","usgsCitation":"Ryder, R., Aggen, K., Hettinger, R.D., Law, B.E., Miller, J.J., Nuccio, V.F., Perry, W.J., Prensky, S.E., Filipo, J.J., and Wandrey, C.J., 1996, Possible continuous-type (unconventional) gas accumulation in the Lower Silurian \"Clinton\" sands, Medina Group and Tuscarora Sandstone in the Appalachian Basin; a progress report of the 1995 project activities: U.S. Geological Survey Open-File Report 96-42, iv, 82 p. :ill., maps (some col.); 28 cm., https://doi.org/10.3133/ofr9642.","productDescription":"iv, 82 p. :ill., maps (some col.); 28 cm.","costCenters":[],"links":[{"id":152949,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1996/0042/report-thumb.jpg"},{"id":9116,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/of/1996/of96-042/","linkFileType":{"id":5,"text":"html"}},{"id":51489,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1996/0042/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ad6e4b07f02db683d3b","contributors":{"authors":[{"text":"Ryder, Robert T.","contributorId":77918,"corporation":false,"usgs":true,"family":"Ryder","given":"Robert T.","affiliations":[],"preferred":false,"id":186720,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Aggen, Kerry L.","contributorId":106749,"corporation":false,"usgs":true,"family":"Aggen","given":"Kerry L.","affiliations":[],"preferred":false,"id":186724,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hettinger, Robert D.","contributorId":102486,"corporation":false,"usgs":true,"family":"Hettinger","given":"Robert","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":186723,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Law, Ben E.","contributorId":85033,"corporation":false,"usgs":true,"family":"Law","given":"Ben","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":186721,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Miller, John J. 0000-0002-9098-0967 jmiller@usgs.gov","orcid":"https://orcid.org/0000-0002-9098-0967","contributorId":3785,"corporation":false,"usgs":true,"family":"Miller","given":"John","email":"jmiller@usgs.gov","middleInitial":"J.","affiliations":[{"id":164,"text":"Central Energy Resources Science Center","active":true,"usgs":true}],"preferred":true,"id":186717,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Nuccio, Vito F. vnuccio@usgs.gov","contributorId":853,"corporation":false,"usgs":true,"family":"Nuccio","given":"Vito","email":"vnuccio@usgs.gov","middleInitial":"F.","affiliations":[],"preferred":true,"id":186715,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Perry, William J. Jr.","contributorId":32498,"corporation":false,"usgs":true,"family":"Perry","given":"William","suffix":"Jr.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":186718,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Prensky, Stephen E.","contributorId":96703,"corporation":false,"usgs":true,"family":"Prensky","given":"Stephen","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":186722,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Filipo, John J.","contributorId":45955,"corporation":false,"usgs":true,"family":"Filipo","given":"John","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":186719,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Wandrey, Craig J. cwandrey@usgs.gov","contributorId":1590,"corporation":false,"usgs":true,"family":"Wandrey","given":"Craig","email":"cwandrey@usgs.gov","middleInitial":"J.","affiliations":[{"id":164,"text":"Central Energy Resources Science Center","active":true,"usgs":true}],"preferred":true,"id":186716,"contributorType":{"id":1,"text":"Authors"},"rank":10}]}} ,{"id":38238,"text":"pp1538K - 1996 - Axial structures within the Reelfoot Rift delineated with magnetotelluric surveys","interactions":[],"lastModifiedDate":"2012-02-02T00:09:51","indexId":"pp1538K","displayToPublicDate":"1996-09-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":331,"text":"Professional Paper","code":"PP","onlineIssn":"2330-7102","printIssn":"1044-9612","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"1538","chapter":"K","title":"Axial structures within the Reelfoot Rift delineated with magnetotelluric surveys","docAbstract":"In the winter of 1811-12, three of the largest historic earthquakes in the United States occurred near New Madrid, Mo. Seismicity continues to the present day throughout a tightly clustered pattern of epicenters centered on the bootheel of Missouri, including parts of northeastern Arkansas, northwestern Tennessee, western Kentucky, and southern Illinois. In 1990, the New Madrid seismic zone/Central United States became the first seismically active region east of the Rocky Mountains to be designated a priority research area within the Natural Earthquake Hazards Reduction Program (NEHRP). This Professional Paper is a collection of papers, some published separately, presenting results of the newly intensified research program in this area. Major components of this research program include tectonic framework studies, seismicity and deformation monitoring and modeling, improved seismic hazard and risk assessments, and cooperative hazard mitigation studies.","language":"ENGLISH","doi":"10.3133/pp1538K","usgsCitation":"Rodriguez, B.D., Stanley, W.D., and Williams, J.M., 1996, Axial structures within the Reelfoot Rift delineated with magnetotelluric surveys: U.S. Geological Survey Professional Paper 1538, p. K1-K30, https://doi.org/10.3133/pp1538K.","productDescription":"p. K1-K30","costCenters":[],"links":[{"id":124266,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/pp/1538k/report-thumb.jpg"},{"id":64605,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/pp/1538k/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a82e4b07f02db64ae60","contributors":{"authors":[{"text":"Rodriguez, B. D.","contributorId":6084,"corporation":false,"usgs":true,"family":"Rodriguez","given":"B.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":219398,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Stanley, W. D.","contributorId":86756,"corporation":false,"usgs":true,"family":"Stanley","given":"W.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":219399,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Williams, J. M.","contributorId":91142,"corporation":false,"usgs":true,"family":"Williams","given":"J.","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":219400,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":26473,"text":"wri954215 - 1996 - Soil, water, and streambed quality at a demolished asphalt plant, Fort Bragg, North Carolina, 1992-94","interactions":[],"lastModifiedDate":"2017-01-27T11:47:14","indexId":"wri954215","displayToPublicDate":"1996-09-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"95-4215","title":"Soil, water, and streambed quality at a demolished asphalt plant, Fort Bragg, North Carolina, 1992-94","docAbstract":"A number of potentially hazardous chemicals were used at an asphalt plant on the Fort Bragg U.S. Army Reservation near Fayetteville, North Carolina. This plant was demolished in the late 1960's. Samples collected from soil, ground water, surface water, and streambed sediment were tested for the presence of contaminants. The sediment immediately underlying the demolished asphalt plant site consists mainly of sands, silts, and clayey sands with interbedded clay occurring at various depths. About 12 inches of rainfall per year infiltrate the unconfined surficial aquifer. The water table in this area is about 233 to 243 feet above sea level. Local ground water moves laterally, mainly towards the north- to-northwest at a rate of about 35 feet per year. where it discharges to Tank Creek, Little River, or one of their tributaries. A series of confining clays separate the surficial aquifer from the underlying upper Cape Fear aquifer. These clays help retard vertical migration of constituents dissolved in ground water. The saprolite-bedrock aquifer lies below the upper Cape Fear aquifer. In general ground water in the seven monitoring wells screened in the upper and lower part of the surficial aquifer did not contain detectable concentrations of chemicals related to past asphalt-plant activities. A small number of chemicals that were assumed to be unrelated to the asphalt plant were present in some of the study area monitoring wells. Ground water in four wells contained concentrations of organochlorine pesticides. Of these pesticides, concentrations of gamma-benzene hexachloride (lindane) (maximum of 0.76 micrograms per liter) exceeded the U.S. Environmental Protection Agency maximum contaminant level of 0.2 micrograms per liter in two wells. In addition, one well contained a trichloroethane concentration (7.7 micrograms per liter) that is assumed to be unrelated to demolished asphalt-plant operations, but exceeded the U.S. Environmental Protection Agency maximum contaminant level of 5.0 micrograms per liter. One well contained a fluoride concentration of 5.2 milligrams per liter that exceeded the U.S. Environmental Protection Agency maximum contaminant level of 4.0 milligrams per liter. Total and dissolved metals concentrations were generally typical of background levels. Some of the wells contained elevated levels of chloride (maximum of 749 milligrams per liter), specific conductance (maximum of 2,780 microsiemens per centimeter at 25 degrees Celsius), and dissolved solids (maximum of 1,520 milligrams per liter). Twelve of twenty-two soil samples that were collected at various depths at monitoring-well locations did not contain volatile organic compounds or polynuclear aromatic hydrocarbons. The remaining ten soil samples contained very low concentrations of polynuclear aromatic hydrocarbons and (or) analytical laboratory-related volatile organic compounds. The maximum concentrations were for fluoranthene and pyrene, at 780 and 750 micrograms per kilogram, respectively. In general, the polynuclear aromatic hydrocarbon concentrations were in sediment near the land surface. Streambed sediment from an unnamed, eastern tributary to Tank Creek in the eastern part of the site contained a small number of organochlorine pesticide compounds (a maximum of 1,400 milligrams per kilogram of 4,4'-DDD) and total petroleum hydrocarbons (113 milligrams per kilogram). Concentrations of metals and other inorganic constituents were generally typical of background concentrations. Surface water in this tributary did not contain elevated concentrations of anthropogenic chemicals.","language":"ENGLISH","publisher":"U.S. Geological Survey ;\r\nEarth Science Information Center, Open-File Reports Section [distributor],","doi":"10.3133/wri954215","usgsCitation":"Campbell, T., 1996, Soil, water, and streambed quality at a demolished asphalt plant, Fort Bragg, North Carolina, 1992-94: U.S. Geological Survey Water-Resources Investigations Report 95-4215, viii, 92 p. :ill., maps ;28 cm., https://doi.org/10.3133/wri954215.","productDescription":"viii, 92 p. :ill., maps ;28 cm.","costCenters":[{"id":13634,"text":"South Atlantic Water Science Center","active":true,"usgs":true}],"links":[{"id":158339,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1995/4215/report-thumb.jpg"},{"id":55292,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1995/4215/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"country":"United States","state":"North Carolina","city":"Fort Bragg","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -79.62890625,\n 34.79576153473033\n ],\n [\n -79.62890625,\n 36.09349937380574\n ],\n [\n -78.145751953125,\n 36.09349937380574\n ],\n [\n -78.145751953125,\n 34.79576153473033\n ],\n [\n -79.62890625,\n 34.79576153473033\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49efe4b07f02db5edbc8","contributors":{"authors":[{"text":"Campbell, T.R.","contributorId":99594,"corporation":false,"usgs":true,"family":"Campbell","given":"T.R.","email":"","affiliations":[],"preferred":false,"id":196454,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":26814,"text":"wri954154 - 1996 - Technique for estimating magnitude and frequency of peak flows in Maryland","interactions":[],"lastModifiedDate":"2012-02-02T00:08:32","indexId":"wri954154","displayToPublicDate":"1996-09-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"95-4154","title":"Technique for estimating magnitude and frequency of peak flows in Maryland","docAbstract":"Methods are presented for estimating peak-flow magnitudes of selected frequencies for drainage basins in Maryland. The methods were developed by generalized least-squares regression techniques using data from 219 streamflow-gaging stations in and near Maryland, and apply to peak flows with recurrence intervals of 2, 5, 10, 25, 50, 100, and 500 years. The State is divided into five hydrologic regions: the Appalachian Plateaus and Allegheny Ridges region, the Blue Ridge and Great Valley region, the Piedmont region, the Western Coastal Plain region, and the Eastern Coastal Plain region. Sets of equations for calculating peak discharges based on physical basin characteristics and their associated standard errors of prediction are provided for each of the five hydrologic regions. Basin characteristics and flood-frequency characteristics are tabulated for 236 streamflow- gaging stations in Maryland and surrounding States. Methods of estimating peak flows at sites in Maryland for ungaged and gaged sites are presented.","language":"ENGLISH","publisher":"U.S. Geological Survey ;\r\nEarth Science Information Center, Open-File Reports Section [distributor],","doi":"10.3133/wri954154","usgsCitation":"Dillow, J., 1996, Technique for estimating magnitude and frequency of peak flows in Maryland: U.S. Geological Survey Water-Resources Investigations Report 95-4154, iv, 55 p. with errata : ill., maps ; 28 cm., https://doi.org/10.3133/wri954154.","productDescription":"iv, 55 p. with errata : ill., maps ; 28 cm.","costCenters":[],"links":[{"id":158402,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"},{"id":2097,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.water.usgs.gov/wri954154/","linkFileType":{"id":5,"text":"html"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4adce4b07f02db6861bb","contributors":{"authors":[{"text":"Dillow, Jonathan J.A.","contributorId":18412,"corporation":false,"usgs":true,"family":"Dillow","given":"Jonathan J.A.","affiliations":[],"preferred":false,"id":197052,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":29969,"text":"wri954167 - 1996 - Discharge, water-quality characteristics, and nutrient loads from McKay Bay, Delaney Creek, and East Bay, Tampa, Florida, 1991-1993","interactions":[],"lastModifiedDate":"2012-02-02T00:09:02","indexId":"wri954167","displayToPublicDate":"1996-09-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"95-4167","title":"Discharge, water-quality characteristics, and nutrient loads from McKay Bay, Delaney Creek, and East Bay, Tampa, Florida, 1991-1993","docAbstract":"Nutrient enrichment in Tampa Bay has caused a decline in water quality in the estuary. Efforts to reduce the nutrient loading to Tampa Bay have resulted in improvement in water quality from 1981 to 1991. However, Tampa Bay still is onsidered enriched with nutrients. Water quality in East Bay (located at the northeastern part of Hillsborough Bay, which is an embayment in Tampa Bay) is not improving at the same rate as the rest of the bay. East Bay is the center of shipping activity in Tampa Bay and the seventh largest port in the United States. One of the primary cargoes is phosphate ore and related products such as fertilizer. The potential for nutrient loading to East Bay from shipping activities is high and has not previously been measured. Nitrogen and phosphorus loads from East Bay to Hillsborough Bay were measured during selected time periods during June 1992 through May 1993; these data were used to estimate seasonal and annual loads. These loads were evaluated to determine whether the loss of fertilizer products from shipping activities resulted in increased nutrient loading to Hillsborough Bay. Discharge was measured, and water-quality samples were collected at the head of East Bay (exiting McKay Bay), and at the mouth of East Bay. Discharge and nitrogen and phosphorus concentrations for the period June 1992 through May 1993 were used to compute loads. Discharges from McKay Bay, Delaney Creek, and East Bay are highly variable because of the effect of tide. Flow patterns during discharge measurements generally were unidirectional in McKay Bay and Delaney Creek, but more complex, bidirectional patterns were observed at the mouth of East Bay. Tidally affected discharge data were digitally filtered with the Godin filter to remove the effects of tide so that residual, or net, discharge could be determined. Daily mean discharge from McKay Bay ranged from -1,900 to 2,420 cubic feet per second; from Delaney Creek, -3.8 to 162 cubic feet per second; and from East Bay, -437 to 3,780 cubic feet per second. Water quality in McKay Bay, Delaney Creek, and East Bay varies vertically, areally, and seasonally. Specific conductance and concentrations of phosphorus and ammonia nitrogen were greater near the bottom than near the surface at the head and mouth of East Bay. Concentrations of total nitrogen and ammonia plus organic nitrogen generally were greater at the head of East Bay than at the mouth, indicating that McKay Bay is the primary source of nitrogen to East Bay. Concentrations of total ammonia nitrogen, nitrite plus nitrate nitrogen, phosphorus, orthophosphorus, and suspended solids and values of turbidity and specific conductance generally were greater at the mouth of East Bay than at the head. The greatest concentrations of nitrogen and phosphorus were measured in Delaney Creek. In East Bay and McKay Bay, the greatest concentrations of nitrogen, phosphorus, and ammonia plus organic nitrogen occurred in summer, whereas turbidity, specific conductance, and concentrations of suspended solids were greater in winter. The greatest daily mean loads from McKay Bay and East Bay occurred in late June 1992 and April and May 1993 and coincided with periods of daily mean discharge greater than about 2,000 cubic feet per second. Although concentrations of nitrogen and phosphorus were greater in Delaney Creek than in McKay Bay and East Bay, loads were minimal because of minimal discharges from Delaney Creek. Monthly loads of total nitrogen ranged from about 20 tons to about 83 tons at McKay Bay; from about 1 ton to 4.2 tons at Delaney Creek; and from about 17 tons to 76 tons at the mouth of East Bay. Monthly loads of phosphorus ranged from about 11 tons to about 45 tons at McKay Bay; from about 0.62 ton to 2.6 tons at Delaney Creek; and from about 10 tons to about 45 tons at the mouth of East Bay. The results of this study indicate that nitrogen and phosphorus loads from the basin draining directly to East Bay (excluding loads from the McKa","language":"ENGLISH","publisher":"U.S. Geological Survey ;\r\nEarth Science Information Center, Open-File Reports Section [distributor],","doi":"10.3133/wri954167","usgsCitation":"Stoker, Y., Levesque, V., and Fritz, E., 1996, Discharge, water-quality characteristics, and nutrient loads from McKay Bay, Delaney Creek, and East Bay, Tampa, Florida, 1991-1993: U.S. Geological Survey Water-Resources Investigations Report 95-4167, v, 47 p. :ill. (some col.), maps ;28 cm., https://doi.org/10.3133/wri954167.","productDescription":"v, 47 p. :ill. (some col.), maps ;28 cm.","costCenters":[],"links":[{"id":2434,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.water.usgs.gov/wri954167","linkFileType":{"id":5,"text":"html"}},{"id":119526,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/wri_95_4167.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a82e4b07f02db64a9ba","contributors":{"authors":[{"text":"Stoker, Y.E.","contributorId":13253,"corporation":false,"usgs":true,"family":"Stoker","given":"Y.E.","email":"","affiliations":[],"preferred":false,"id":202453,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Levesque, V.A.","contributorId":56268,"corporation":false,"usgs":true,"family":"Levesque","given":"V.A.","email":"","affiliations":[],"preferred":false,"id":202455,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Fritz, E.M.","contributorId":26337,"corporation":false,"usgs":true,"family":"Fritz","given":"E.M.","email":"","affiliations":[],"preferred":false,"id":202454,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":26714,"text":"wri954279 - 1996 - Hydrogeology and simulation of ground-water flow at the South Well Field, Columbus, Ohio","interactions":[],"lastModifiedDate":"2012-02-02T00:08:30","indexId":"wri954279","displayToPublicDate":"1996-09-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"95-4279","title":"Hydrogeology and simulation of ground-water flow at the South Well Field, Columbus, Ohio","docAbstract":"The City of Columbus, Ohio, operates four radial collector wells in southern Franklin County. The 'South Well Field' is completed in permeable outwash and ice-contact deposits, upon which flow the Scioto River and Big Walnut Creek. The wells are designed to yield approximately 42 million gallons per day; part of that yield results from induced infiltration of surface water from the Scioto River and Big Walnut Creek. The well field supplied up to 30 percent of the water supply of southern Columbus and its suburbs in 1991. This report describes the hydrogeology of southern Franklin County and a tran sient three-dimensional, numerical ground-water- flow model of the South Well Field.\r\n\r\nThe primary source of ground water in the study area is the glacial drift aquifer. The glacial drift is composed of sand, gravel, and clay depos ited during the Illinoian and Wisconsinan glaciations. In general, thick deposits of till containing lenses of sand and gravel dominate the drift in the area west of the Scioto River. The thickest and most productive parts of the glacial drift aquifer are in the buried valleys in the central and eastern parts of the study area underlying the Scioto River and Big Walnut Creek. Horizontal hydraulic conductivity of the glacial drift aquifer differs spa tially and ranges from 30 to 375 feet per day. The specific yield ranges from 0.12 to 0.30.\r\n\r\nThe secondary source of ground water within the study area is the underlying carbonate bedrock aquifer, which consists of Silurian and Devonian limestones, dolomites, and shales. The horizontal hydraulic conductivity of the carbonate bedrock aquifer ranges from 10 to 15 feet per day. The storage coefficient is about 0.0002. \r\n\r\nThe ground-water-flow system in the South Well Field area is recharged by precipitation, regional ground-water flow, and induced stream infiltration. Yearly recharge rates varied spatially and ranged from 4.0 to 12.0 inches. \r\n\r\nThe three-dimensional, ground-water-flow model was constructed by use of the U.S. Geological Survey three-dimensional finite-difference ground-water-flow code. Recharge, boundary flux, and river leakage are the principal sources of water to the flow system. The study area is bounded on the north and south by streamlines, with flow entering the area from the east and west. Areal recharge is contributed throughout the study area, although a comparatively high percentage of precipitation reaches the water table in the area east of the Scioto River where little surface drain age exists. Ground-water flow is downward in the uplands of the Scioto River, and upward near the river in the glacial drift and carbonate bedrock aquifers.\r\n\r\nThe numerical model contains 53 rows, 45 columns, and 3 layers. The uppermost two layers represent the glacial drift. The bottom layer represents the carbonate bedrock. The horizontal model grid is variably spaced to account for differences in available data and to simulate heads accurately in specific areas of interest. The length and width of grid cells range from 200 to 2,000 feet; the finer spacings are designed to increase detail in the areas near the collector wells. The model uses 7,155 active nodes. \r\n\r\nMeasurements of water levels from October 1979 were used to represent steady-state conditions before municipal pumping at the well field began. Measurements made during March 1986 were used to represent steady-state conditions after commencement of pumping at the well field. Water levels measured during March 1986 - June 1991 were used for calibration targets in the transient simulations. \r\n\r\nThe transient model was discretized into eight stress periods of 93 to 487 days on the basis of recharge, well-field pumpage, and available water-level data. Transient model calibration was based on seven sets of hydraulic-head measure ments made during March 1986 - June 1991. This time period includes large-scale increases in well- field production associated with a drought in the summer of 1988, an","language":"ENGLISH","publisher":"U.S. Geological Survey ;\r\nEarch Science Information Center, Open-File Reports Section [distributor],","doi":"10.3133/wri954279","usgsCitation":"Cunningham, W.L., Bair, E., and Yost, W., 1996, Hydrogeology and simulation of ground-water flow at the South Well Field, Columbus, Ohio: U.S. Geological Survey Water-Resources Investigations Report 95-4279, iv, 56 p. :ill., maps ;28 cm., https://doi.org/10.3133/wri954279.","productDescription":"iv, 56 p. :ill., maps ;28 cm.","costCenters":[],"links":[{"id":121963,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1995/4279/report-thumb.jpg"},{"id":55589,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1995/4279/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a4be4b07f02db6253b5","contributors":{"authors":[{"text":"Cunningham, W. L.","contributorId":22801,"corporation":false,"usgs":true,"family":"Cunningham","given":"W.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":196873,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bair, E. Scott","contributorId":73231,"corporation":false,"usgs":true,"family":"Bair","given":"E. Scott","affiliations":[],"preferred":false,"id":196875,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Yost, W.P.","contributorId":51791,"corporation":false,"usgs":true,"family":"Yost","given":"W.P.","email":"","affiliations":[],"preferred":false,"id":196874,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":28519,"text":"wri914035 - 1996 - Hydrogeology and simulation of ground-water flow in the alluvial aquifer at Louisville, Kentucky","interactions":[],"lastModifiedDate":"2012-02-02T00:08:52","indexId":"wri914035","displayToPublicDate":"1996-09-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"91-4035","title":"Hydrogeology and simulation of ground-water flow in the alluvial aquifer at Louisville, Kentucky","docAbstract":"The alluvial aquifer at Louisville, Ky., lies in a valley eroded by glacial meltwater that was later partly filled with outwash sand and gravel deposits. The aquifer is primarily unconfined, and the direction of flow is from the adjacent limestone and shale valley wall toward the Ohio River and major pumping centers. Pumpage and water-level data indicate that the alluvial aquifer was in a steady-state condition in November 1962 and again in November 1983. Between these two dates, water-level data indicate a general rise in the water table. A two-dimensional finite-element ground-water-flow model of the alluvial aquifer was calibrated for both the steady-state and the transient-state period of 1962-83. The year 1962 represented a period in time when pumping was nearly three times that in 1983. The simulated steady-state water budget for 1962 indicated that of the total recharge to the aquifer of 5.19 million feet per day, 37.2 percent was flow from the river to pumped wells, 28.3 percent was recharge from rainfall, 19.7 percent was flow across the eastern valley wall, and 14.8 percent was upward flow from the bedrock. Discharge from the aquifer was to wells (68.9 percent) and to the Ohio River (31.1 percent). The simulated steady-state water budget for 1983 indicated that of the total recharge to the aquifer of 4.11 million feet per day, 42.6 percent was recharge from rainfall, 18.2 percent was flow across the eastern valley wall, 17.8 percent was flow from the river to pumped wells, 15.6 percent was upward flow from the bedrock, and 5.8 percent was flow from septic systems. The transient simulation resulted in an acceptable match between measured and simulated hydrographs. This gave additional confidence to the model calibration, choice of boundary conditions, and published values of specific yield. Both steady-state and transient-state models demonstrated that the main source of water needed to meet increased pumping requirements was induced flow from the Ohio River.","language":"ENGLISH","publisher":"U.S. Geological Survey ;\r\nEarth Science Information Center, Open-File Reports Section [distributor],","doi":"10.3133/wri914035","usgsCitation":"Lyverse, M.A., Starn, J., and Unthank, M., 1996, Hydrogeology and simulation of ground-water flow in the alluvial aquifer at Louisville, Kentucky: U.S. Geological Survey Water-Resources Investigations Report 91-4035, vi, 41 p. :ill., maps ;28 cm., https://doi.org/10.3133/wri914035.","productDescription":"vi, 41 p. :ill., maps ;28 cm.","costCenters":[],"links":[{"id":123608,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1991/4035/report-thumb.jpg"},{"id":57319,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1991/4035/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a4be4b07f02db62562d","contributors":{"authors":[{"text":"Lyverse, M. A.","contributorId":89151,"corporation":false,"usgs":true,"family":"Lyverse","given":"M.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":199954,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Starn, J.J.","contributorId":69591,"corporation":false,"usgs":true,"family":"Starn","given":"J.J.","email":"","affiliations":[],"preferred":false,"id":199953,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Unthank, M.D.","contributorId":35351,"corporation":false,"usgs":true,"family":"Unthank","given":"M.D.","email":"","affiliations":[],"preferred":false,"id":199952,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":68031,"text":"ha736 - 1996 - Geohydrology of the shallow aquifers in the Denver metropolitan area, Colorado","interactions":[],"lastModifiedDate":"2015-10-28T11:25:32","indexId":"ha736","displayToPublicDate":"1996-09-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":318,"text":"Hydrologic Atlas","code":"HA","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"736","title":"Geohydrology of the shallow aquifers in the Denver metropolitan area, Colorado","docAbstract":"The Denver metropolitan area is underlain by shallow layers of water-bearing sediments (aquifers) consisting of unconsolidated gravel, sand, silt, and clay. The depth to water in these aquifers is less than 20 feet in much of the area, and the aquifers provide a ready source of water to numerous shallow, small-capacity wells. The shallow depth to water also makes the aquifers susceptible to contamination from the land surface. Water percolating downward from residential, commercial, and industrial property, spills of hazardous materials, and leaks from underground storage tanks and pipelines can cause contaminants to enter the shallow aquifers. Wet basements, unstable foundation materials, and waterlogged soils also are common in areas of very shallow ground water.
Knowledge of the extent, thickness, and water-table altitude of the shallow aquifers is incomplete. This, coupled with the complexity of development in this large metropolitan area, makes effective use, management, and protection of these aquifers extremely difficult. Mapping of the geologic and hydrologic characteristics of these aquifers would provide the general public and technical users with information needed to better use, manage, and protect this water resource. A study to map the geohydrology of shallow aquifers in the Denver metropolitan area was begun in 1994. The work was undertaken by the U.S. Geological Survey in cooperation with the U.S. Army-Rocky Mountain Arsenal, U.S. Department of Energy-Rocky Flats Field Office, Colorado Department of Public Health and Environment, Colorado Department of Natural Resources-State Engineers Office, Denver Water Department, Littleton-Englewood Wastewater Treatment Plant, East Cherry Creek Valley Water and Sanitation District, Metro Wastewater Reclamation District, Willows Water District, and the cities of Aurora, Lakewood, and Thornton.
This report presents the results of a systematic mapping of the extent, thickness, and water-table altitude of the shallow aquifers in a 700-square-mile part of the greater Denver metropolitan area (fig. 1). The five sheets in this report (figs. 2-7) show (1) the thickness and extent of the unconsolidated sediments that overlie bedrock formations in the area, (2) the altitude and configuration of the buried bedrock surface, (3) the altitude of the water table and direction of ground-water movement, (4) the saturated thickness of the shallow aquifers, and (5) the depth to the water table in the shallow aquifers. The maps primarily are intended to indicate the general trends in altitude and thickness of the aquifers and are not intended to define conditions at specific sites.
One of the often-stated functions of wetlands is their ability to remove sediments and other particulates from water, thus improving water quality in the adjacent aquatic system. However, actual rates of suspended sediment removal have rarely been measured in freshwater wetland systems. To address this issue, suspended sediment dynamics were measured in a 85-km2 bottomland hardwood (BLH) wetland adjacent to the highly turbid Cache River in eastern Arkansas during the 1988–1990 water years. A suspended sediment mass balance was calculated using depth-integrated, flow-weighted daily measurements at wetland inflow and outflow points. Over the three-year period, suspended sediment load decreased an average of 14% between upstream and downstream sampling points. To test the idea that the suspended sediments were retained by the adjacent wetland and to determine what portion of the BLH forest was most responsible for retaining the suspended sediments, concurrent measurements of sediment accretion were made at 30 sites in the wetland using feldspar clay marker horizons, sedimentation disks, the137cesium method, and dendrogeomorphic techniques. Sedimentation rates exceeding 1 cm/yr were measured in frequently flooded areas dominated by Nyssa aquatica and Taxodium distichum. Maximum sedimentation rates did not occur on the natural levee, as would be predicted by classical fluvial geomorphology, but in the “first bottom,” where retention time of the water reached a maximum. Multiple regression was used to relate sedimentation rates with several physical and biological factors. A combination of distance from the river, flood duration, and tree basal area accounted for nearly 90% of the variation in sedimentation rates.
","language":"English","publisher":"Springer Nature","doi":"10.1007/BF03161323","issn":"02775212","usgsCitation":"Kleiss, B., 1996, Sediment retention in a bottomland hardwood wetland in eastern Arkansas: Wetlands, v. 16, no. 3, p. 321-333, https://doi.org/10.1007/BF03161323.","productDescription":"13 p.","startPage":"321","endPage":"333","costCenters":[],"links":[{"id":503770,"rank":2,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://digitalcommons.lsu.edu/gradschool_disstheses/6025","text":"External Repository"},{"id":226719,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Arkansas","otherGeospatial":"eastern Arkansas","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -91.21480606880425,\n 36.05701646084884\n ],\n [\n -91.6592849714275,\n 34.425186910956285\n ],\n [\n -91.5122639998533,\n 32.53441399953529\n ],\n [\n -90.84299278500842,\n 32.331053891219526\n ],\n [\n -90.86333874610101,\n 33.56914964201549\n ],\n [\n -89.5141845795728,\n 36.16899487873114\n ],\n [\n -89.77878071589814,\n 36.5449158948269\n ],\n [\n -91.21480606880425,\n 36.05701646084884\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"16","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b89bce4b08c986b316e7f","contributors":{"authors":[{"text":"Kleiss, B.A.","contributorId":107320,"corporation":false,"usgs":false,"family":"Kleiss","given":"B.A.","email":"","affiliations":[],"preferred":false,"id":381315,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70018987,"text":"70018987 - 1996 - Ground-water-flow conditions within a bottomland hardwood wetland, eastern Arkansas","interactions":[],"lastModifiedDate":"2026-04-27T17:09:27.608481","indexId":"70018987","displayToPublicDate":"1996-09-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3750,"text":"Wetlands","onlineIssn":"1943-6246","printIssn":"0277-5212","active":true,"publicationSubtype":{"id":10}},"title":"Ground-water-flow conditions within a bottomland hardwood wetland, eastern Arkansas","docAbstract":"Water levels were measured monthly at 9 staff gages and 35 wells along two transects within the Black Swamp bottomland hardwood wetland and perpendicular to the Cache River in eastern Arkansas from December 1989 to September 1992 in order to (1) describe the ground-water-flow conditions at locations within a bottomland hardwood wetland and (2) determine the relation between the frequency of different ground-water-flow conditions and physical characteristics within the wetland. Three ground-water-flow conditions predominated at various times in the Black Swamp: (1) discharge of water from the alluvial aquifer to the wetland, (2) recharge of water from the wetland into the alluvial aquifer, and (3) flow of water from the wetland into the alluvial aquifer and then to the nearby Cache River (local flow). Analyses of hydraulic head differences between surface and ground water indicate that discharge occurred 31% of the measurement times at both transects. Recharge occurred 39% of the measurement times and tended to occur more often at locations that are far from the Cache River and that overlie low ground-water levels in the lower part of the alluvial aquifer. Local ground-water flow occurred 28% of the measurement times and tended to occur more often at locations close to the Cache River. Ground-water pumpage results in water-level declines in the lower part of the alluvial aquifer near the Black Swamp wetland. When compared with an area not affected by pumping, these lower ground-water levels increased the frequency of recharge of Black Swamp water into the alluvial aquifer by nearly a factor of 7, decreased the frequency of local ground-water flow to the Cache River to less than half, and decreased the frequency of discharge by about 22%.
","language":"English","publisher":"Springer Nature","doi":"10.1007/BF03161324","issn":"02775212","usgsCitation":"Gonthier, G., 1996, Ground-water-flow conditions within a bottomland hardwood wetland, eastern Arkansas: Wetlands, v. 16, no. 3, p. 334-346, https://doi.org/10.1007/BF03161324.","productDescription":"13 p.","startPage":"334","endPage":"346","costCenters":[],"links":[{"id":226718,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Arkansas","otherGeospatial":"eastern Arkansas","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -91.21480606880425,\n 36.05701646084884\n ],\n [\n -91.6592849714275,\n 34.425186910956285\n ],\n [\n -91.5122639998533,\n 32.53441399953529\n ],\n [\n -90.84299278500842,\n 32.331053891219526\n ],\n [\n -90.86333874610101,\n 33.56914964201549\n ],\n [\n -89.5141845795728,\n 36.16899487873114\n ],\n [\n -89.77878071589814,\n 36.5449158948269\n ],\n [\n -91.21480606880425,\n 36.05701646084884\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"16","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a2d7ae4b0c8380cd5bef4","contributors":{"authors":[{"text":"Gonthier, G.J.","contributorId":27484,"corporation":false,"usgs":true,"family":"Gonthier","given":"G.J.","email":"","affiliations":[],"preferred":false,"id":381314,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70019041,"text":"70019041 - 1996 - Earthquakes and the southeastern boundary of the intact Iapetan margin in eastern North America","interactions":[],"lastModifiedDate":"2025-07-29T16:24:10.187499","indexId":"70019041","displayToPublicDate":"1996-09-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3372,"text":"Seismological Research Letters","onlineIssn":"1938-2057","printIssn":"0895-0695","active":true,"publicationSubtype":{"id":10}},"title":"Earthquakes and the southeastern boundary of the intact Iapetan margin in eastern North America","docAbstract":"Earthquakes at three localities in eastern North America have been attributed on geological and seismological grounds to compressional reactivation of some of the late Proterozoic or early Paleozoic normal faults in the northeast-trending Iapetan passive margin. Assessment of seismic hazard can be aided by identifying the boundaries of the area of Iapetan faulting. A previous paper located the northwestern boundary. This report interprets deep seismic-reflection profiles as showing that the margin comprises a seismically active northwestern part, where Precambrian crust contains some Iapetan faults but remains mostly as it was formed, and a southeastern part, where later deformations likely destroyed or modified the Precambrian crust and Iapetan faults. Accordingly, the boundary between the northwestern and southeastern parts of the margin, which coincides approximately with the Appalachian gravity gradient, can be taken as the southeastern limit of potentially seismogenic Iapetan faults.
","language":"English","publisher":"GeoScienceWorld","doi":"10.1785/gssrl.67.5.77","issn":"00128287","usgsCitation":"Wheeler, R.L., 1996, Earthquakes and the southeastern boundary of the intact Iapetan margin in eastern North America: Seismological Research Letters, v. 67, no. 5, p. 77-83, https://doi.org/10.1785/gssrl.67.5.77.","productDescription":"7 p.","startPage":"77","endPage":"83","costCenters":[],"links":[{"id":226273,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Canada, United States","otherGeospatial":"eastern North America","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -54.2502026221228,\n 52.455495547752676\n ],\n [\n -77.31466901821747,\n 41.2383548936905\n ],\n [\n -80.48862204496822,\n 34.752591778926934\n ],\n [\n -86.90152402114032,\n 31.46634422283111\n ],\n [\n -84.24811384541448,\n 25.84563151864664\n ],\n [\n -79.94840683558355,\n 24.914617306669044\n ],\n [\n -74.23579295630763,\n 30.63667351222948\n ],\n [\n -68.5231790770317,\n 36.35872971778991\n ],\n [\n -59.510799405663164,\n 43.74758113158556\n ],\n [\n -50.81989444848227,\n 47.09943858375916\n ],\n [\n -54.2502026221228,\n 52.455495547752676\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"67","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0511e4b0c8380cd50c53","contributors":{"authors":[{"text":"Wheeler, R. L.","contributorId":34916,"corporation":false,"usgs":true,"family":"Wheeler","given":"R.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":381496,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":28516,"text":"wri964010 - 1996 - Geohydrology and contamination at the Michigan Department of Transportation maintenance garage area, Kalamazoo County, Michigan","interactions":[],"lastModifiedDate":"2017-01-12T13:02:49","indexId":"wri964010","displayToPublicDate":"1996-08-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"96-4010","title":"Geohydrology and contamination at the Michigan Department of Transportation maintenance garage area, Kalamazoo County, Michigan","docAbstract":"A leaking underground storage tank was removed from the Michigan Department of Transportation maintenance garage area in Kalamazoo County., Mich., in 1985. The tank had been leaking unleaded gasoline. Although a remediation system was operational at the site for several years after the tank was removed, ground-water samples collected from monitoring wells in the area consistently showed high concentrations of benzene, toluene. ethylbenzene, and xylenes--indicators of the presence of gasoline. The U.S. Geological Survey did a study in cooperation with the Michigan Department of Transportation, to define the geology, hydrology, and occurrence of gasoline contamination in the maintenance garage area. The aquifer affected by gasoline contamination is an unconfined glaci'a.l sand and gravel aquifer. The average depth to water in the study area is about 74.7 feet. Water-level fluctuations are small; maximum fluctuation was slightly more than 1 foot during August 1993-August 1994. Hydraulic conductivities based on aquifer-test data collected for the study and estimated by use of the Cooper-Jacob method of solution ranged from 130 to 144 feet per day. Ground water is moving in an east-southeasterly direction at a rate of about I foot per day. Leakage from perforated pipes leading from the underground storage tanks to the pump station was identified as a second source of gasoline contamination\t to saturated and unsaturated zones. The existence of this previously unknown second source is part of the reason that previous remediation efforts were ineffective. Residual contaminants in the unsaturated zone are expected to continue to move to the water table with recharge, except in a small area covered by asphalt at the land surface. The gasoline plume from the perforated pipe source has merged with that from the leaking underground storage tank, and the combined plume in the saturated zone is estimated to cover an area of 30,000 square feet. The combined plume is in the upper 20 feet of the saturated zone. The relative distribution of benzene, toluene, ethylbenzene, and xylenes indicate that factors such as sorption, solubility, and susceptibility to microbial degradation are affecting the movement of the combined plume. Given these factors, the plume is expected to move at a rate of less than 1 foot per day.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Lansing, MI","doi":"10.3133/wri964010","collaboration":"Prepared in cooperation with the Michigan Department of Transportation","usgsCitation":"Lynch, E.A., and Huffman, G., 1996, Geohydrology and contamination at the Michigan Department of Transportation maintenance garage area, Kalamazoo County, Michigan: U.S. Geological Survey Water-Resources Investigations Report 96-4010, v, 31 p., https://doi.org/10.3133/wri964010.","productDescription":"v, 31 p.","costCenters":[{"id":382,"text":"Michigan Water Science Center","active":true,"usgs":true}],"links":[{"id":57316,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1996/4010/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":123586,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1996/4010/report-thumb.jpg"}],"country":"United States","state":"Michigan","county":"Kalamazoo County","otherGeospatial":"Department of Transportation Maintenance Garage Area","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -85.664167,\n 42.283611\n ],\n [\n -85.664167,\n 42.292222\n ],\n [\n -85.659167,\n 42.292222\n ],\n [\n -85.659167,\n 42.283611\n ],\n [\n -85.664167,\n 42.283611\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b24e4b07f02db6aec59","contributors":{"authors":[{"text":"Lynch, E. A.","contributorId":99167,"corporation":false,"usgs":true,"family":"Lynch","given":"E.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":199947,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Huffman, G.C.","contributorId":44150,"corporation":false,"usgs":true,"family":"Huffman","given":"G.C.","email":"","affiliations":[],"preferred":false,"id":199946,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":39630,"text":"pp1404I - 1996 - Hydrogeologic framework of the North Carolina coastal plain","interactions":[{"subject":{"id":16592,"text":"ofr87690 - 1989 - Hydrogeologic framework of the North Carolina Coastal Plain aquifer system","indexId":"ofr87690","publicationYear":"1989","noYear":false,"title":"Hydrogeologic framework of the North Carolina Coastal Plain aquifer system"},"predicate":"SUPERSEDED_BY","object":{"id":39630,"text":"pp1404I - 1996 - Hydrogeologic framework of the North Carolina coastal plain","indexId":"pp1404I","publicationYear":"1996","noYear":false,"chapter":"I","title":"Hydrogeologic framework of the North Carolina coastal plain"},"id":1}],"lastModifiedDate":"2025-04-17T19:50:05.684131","indexId":"pp1404I","displayToPublicDate":"1996-08-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":331,"text":"Professional Paper","code":"PP","onlineIssn":"2330-7102","printIssn":"1044-9612","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"1404","chapter":"I","title":"Hydrogeologic framework of the North Carolina coastal plain","docAbstract":"The hydrogeologic framework of the North Carolina Coastal Plain aquifer system consists of 10 aquifers separated by 9 confining units. From top to bottom, the aquifers are the surficial aquifer, Yorktown aquifer, Pungo River aquifer, Castle Hayne aquifer, Beaufort aquifer, Peedee aquifer, Black Creek aquifer, upper Cape Fear aquifer, lower Cape Fear aquifer, and Lower Cretaceous aquifer. The uppermost aquifer (the surficial aquifer in most places) is a water-table aquifer, and the bottom of the system is underlain by crystalline bedrock.\r\n\r\nThe sedimentary deposits forming the aquifers are of Holocene to Cretaceous age and are composed mostly of sand, with lesser amounts of gravel and limestone. The confining units between the aquifers are composed primarily of clay and silt. The thickness of the aquifers ranges from zero along the Fall Line to more than 10,000 feet at Cape Hatteras. Prominent structural features are the increasing easterly homoclinal dip of the sediments and the Cape Fear arch, the axis of which trends in a southeast direction.\r\n\r\nStratigraphic continuity was determined from correlations of 161 geophysical logs along with data from drillers? and geologists? logs. Aquifers were defined by means of these logs as well as water-level and water-quality data and evidence of the continuity of pumping effects. Eighteen hydrogeologic sections depict the correlation of these aquifers throughout the North Carolina Coastal Plain.","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/pp1404I","usgsCitation":"Winner, M.D., and Coble, R.W., 1996, Hydrogeologic framework of the North Carolina coastal plain: U.S. Geological Survey Professional Paper 1404, Report: 106 p.; 24 Plates: 52.00 x 25.00 inches or smaller, https://doi.org/10.3133/pp1404I.","productDescription":"Report: 106 p.; 24 Plates: 52.00 x 25.00 inches or 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D. Jr.","contributorId":51766,"corporation":false,"usgs":true,"family":"Winner","given":"M.","suffix":"Jr.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":221845,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Coble, R. W.","contributorId":49380,"corporation":false,"usgs":true,"family":"Coble","given":"R.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":221844,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ]}