The Mw 7.1 Hector Mine, California, earthquake occurred at 9:46 GMT on 16 October 1999. The event caused minimal damage because it was located in a remote, sparsely populated part of the Mojave Desert, approximately 47 miles east-southeast of Barstow, with epicentral coordinates 34.59°N 116.27°W and a hypocentral depth of 5 ± 3 km. Twelve foreshocks, M 1.9-3.8, preceded the mainshock during the previous twelve hours. All of these events were located close to the hypocenter of the mainshock.
The Hector Mine earthquake occurred within the Eastern California Shear Zone (ECSZ). By virtue of its remote location, the societal impact of the Hector Mine earthquake was, fortunately, minimal in spite of the event's appreciable size. The ECSZ is characterized by high seismicity, a high tectonic strain rate, and a broad, distributed zone of north-northwest-trending faults (ECSZ; Figure 1; Dokka and Travis, 1990; Sauber et al., 1986; Sauber et al., 1994; Sieh et al., 1993). Data regarding the slip rates of faults within the ECSZ suggest that on the order of 15% of the Pacific-North American plate motion occurs along this zone (Sauber et al., 1986; Wesnousky, 1986). Most of the faults in the ECSZ have low slip rates and long repeat times for major earthquakes, on the order of several thousands to tens of thousands of years. The occurrence of the Hector Mine earthquake within seven years and only about 30 km east of the 1992 Mw 7.3 Landers earthquake suggests that the closely spaced surface faults in the ECSZ are mechanically related.
The Hector Mine event involved rupture on two previously mapped fault zones—the Bullion Fault and an unnamed, more northerly-trending fault that is informally referred to in this paper as the Lavic Lake Fault (Dibblee, 1966, 1967a,b). Traces of the Bullion Fault exhibit evidence of Holocene displacement and were zoned as active in 1988 under California's Mquist-Priolo Earthquake Fault Zoning Act (Hart and Bryant, 1997). The pattern of rupture along more than one named fault was also observed from the 1992 Landers earthquake (Hauksson et al., 1993; Sieh et al., 1994).
Much of the fault zone that produced the Hector Mine earthquake had been buried by relatively young stream deposits, and the fault scarps in bedrock have a subdued morphology. It appears that these faults have not experienced significant offset for perhaps 10,000 years or more (Hart, 1987). Planned future investigations will refine the age of the last event on these faults. The portion of the Lavic Lake Fault that ruptured between the northern end of the Bullion Mountains and Lavic Lake had not previously been mapped. However, our field investigations have identified ancient, subdued fault scarps along portions of the 1999 rupture zone in this area. It thus appears that the entire segment of the Lavic Lake Fault that was involved in the 1999 event had ruptured in the past. As is typical for most faults within the Eastern California Shear Zone, the rate of movement along the Lavic Lake Fault may be quite slow (<1 mm/yr) and should produce earthquakes only infrequently. This event is a reminder that faults that have ruptured in late Quaternary time, but that lack evidence of Holocene displacement, can still produce earthquakes in this low-slip-rate tectonic setting.
Additionally, the Hector Mine earthquake is noteworthy for a couple of other reasons. First, it clearly produced triggered seismicity over much of southern California, from the rupture zone toward the south-southwest in particular. Second, as we will discuss, the event may provide new data and insight into recently developed paradigms concerning earthquake interactions and the role of static stress changes.
Questions such as these will, of course, be the subject of extensive detailed analyses in years to come. Fortunately, the Hector Mine sequence will provide one of the best data sets obtained to date for a significant earthquake in the United States. Because it occurred when major upgrades to both the regional seismic network (TriNet) and the regional geodetic network (SCIGN) were well underway, the Earth science community will have abundant high-quality data with which to explore the important and interesting questions that have been raised. In this paper, we present and discuss the basic data and preliminary results from the Hector Mine earthquake.
Accurate base maps are a prerequisite for any geologic study, regardless of the objectives. Land-based studies commonly utilize aerial photographs, USGS 7.5-minute quadrangle maps, and satellite images as base maps. Until now, studies that involve the ocean floor have been at a disadvantage due to an almost complete lack of accurate marine base maps. Many base maps of the sea floor have been constructed over the past century but with a wide range in navigational and depth accuracies. Only in the past few years has marine surveying technology advanced far enough to produce navigational accuracy of 1 meter and depth resolutions of 50 centimeters. The Pacific Seafloor Mapping Project of the U.S. Geological Survey's, Western Coastal and Marine Geology Program, Menlo Park, California, U.S.A., in cooperation with the Ocean Mapping Group, University of New Brunswick, Fredericton, Canada, is using this new technology to systematically map the ocean floor and lakes. This type of marine surveying, called multibeam surveying, collects high-resolution bathymetric and backscatter data that can be used for various base maps, GIS coverages, and scientific visualization methods. This is an interactive CD-ROM that contains images, movies, and data of all the surveys the Pacific Seafloor Mapping Project has completed up to January 1999. The images and movies on this CD-ROM, such as shaded relief of the bathymetry, backscatter, oblique views, 3-D views, and QuickTime movies help the viewer to visualize the multibeam data. This CD-ROM also contains ARC/INFO export (.e00) files and full-resolution TIFF images of all the survey sites that can be downloaded and used in many GIS packages.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ds55","usgsCitation":"Dartnell, P., and Gardiner, J.V., 1999, Sea-floor images and data from multibeam surveys in San Francisco Bay, Southern California, Hawaii, the Gulf of Mexico, and Lake Tahoe, California-Nevada (Version 1.0): U.S. Geological Survey Data Series 55, HTML Document; CD-ROM, https://doi.org/10.3133/ds55.","productDescription":"HTML Document; CD-ROM","onlineOnly":"N","additionalOnlineFiles":"Y","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":139677,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"},{"id":403319,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_22610.htm","text":"San Francisco Bay","linkFileType":{"id":5,"text":"html"},"description":"22610"},{"id":109861,"rank":10,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_22617.htm","text":"west of San Diego","linkFileType":{"id":5,"text":"html"},"description":"22617"},{"id":109864,"rank":13,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_22620.htm","text":"east Flower Gardens - Gulf of Mexico","linkFileType":{"id":5,"text":"html"},"description":"22620"},{"id":12400,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/dds/dds-55/","linkFileType":{"id":5,"text":"html"}},{"id":109855,"rank":4,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_22611.htm","text":"NE of the Island of Hawaii","linkFileType":{"id":5,"text":"html"},"description":"22611"},{"id":109860,"rank":9,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_22616.htm","text":"west of Los Angeles","linkFileType":{"id":5,"text":"html"},"description":"22616"},{"id":109862,"rank":11,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_22618.htm","text":"Stetson Bank - Gulf of Mexico","linkFileType":{"id":5,"text":"html"},"description":"22618"},{"id":109856,"rank":5,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_22612.htm","text":"west of the Island of Maui","linkFileType":{"id":5,"text":"html"},"description":"22612"},{"id":109857,"rank":6,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_22613.htm","text":"south and east of Oahu","linkFileType":{"id":5,"text":"html"},"description":"22613"},{"id":109858,"rank":7,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_22614.htm","text":"south of the Island of Kauai","linkFileType":{"id":5,"text":"html"},"description":"22614"},{"id":109859,"rank":8,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_22615.htm","text":"Lake Tahoe","linkFileType":{"id":5,"text":"html"},"description":"22615"},{"id":109863,"rank":12,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_22619.htm","text":"west Flower Gardens - Gulf of Mexico","linkFileType":{"id":5,"text":"html"},"description":"22619"}],"edition":"Version 1.0","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a0ce4b07f02db5fc564","contributors":{"authors":[{"text":"Dartnell, Peter 0000-0002-9554-729X pdartnell@usgs.gov","orcid":"https://orcid.org/0000-0002-9554-729X","contributorId":2688,"corporation":false,"usgs":true,"family":"Dartnell","given":"Peter","email":"pdartnell@usgs.gov","affiliations":[{"id":520,"text":"Pacific Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":149979,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gardiner, James V.","contributorId":44529,"corporation":false,"usgs":true,"family":"Gardiner","given":"James","email":"","middleInitial":"V.","affiliations":[],"preferred":false,"id":149980,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70021851,"text":"70021851 - 1999 - Early evolution of a stratospheric volcanic eruption cloud as observed with TOMS and AVHRR","interactions":[],"lastModifiedDate":"2017-04-07T15:12:28","indexId":"70021851","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2316,"text":"Journal of Geophysical Research D: Atmospheres","active":true,"publicationSubtype":{"id":10}},"title":"Early evolution of a stratospheric volcanic eruption cloud as observed with TOMS and AVHRR","docAbstract":"This paper is a detailed study of remote sensing data from the total ozone mapping spectrometer (TOMS) and the advanced very high resolution radiometer (AVHRR) satellite detectors, of the 1982 eruption of El Chichón, Mexico. The volcanic cloud/atmosphere interactions in the first four days of this eruption were investigated by combining ultraviolet retrievals to estimate the mass of sulfur dioxide in the volcanic cloud [Krueger et al., 1995] with thermal infrared retrievals of the size, optical depth, and mass of fine-grained (1–10 μm radius) volcanic ash [Wen and Rose, 1994]. Our study provides the first direct evidence of gravitational separation of ash from a stratospheric, gas-rich, plinian eruption column and documents the marked differences in residence times of volcanic ash and sulfur dioxide in volcanic clouds. The eruption column reached as high as 32 km [Carey and Sigurdsson, 1986] and was injected into an atmosphere with a strong wind shear, which allowed for an observation of the separation of sulfur dioxide and volcanic ash. The upper, more sulfur dioxide-rich part of the cloud was transported to the west in the stratosphere, while the fine-grained ash traveled to the south in the troposphere. The mass of sulfur dioxide released was estimated at 7.1 × 109 kg with the mass decreasing by approximately 4% 1 day after the peak. The mass of fine-grained volcanic ash detected was estimated at 6.5 × 109 kg, amounting to about 0.7% of the estimated mass of the ash which fell out in the mapped ash blanket close to the volcano. Over the following days, 98% of this remaining fine ash was removed from the volcanic cloud, and the effective radius of ash in the volcanic cloud decreased from about 8 μm to about 4 μm.
","language":"English","publisher":"AGU","doi":"10.1029/1998JD200073","issn":"01480227","usgsCitation":"Schneider, D., Rose, W.I., Coke, L., Bluth, G., Sprod, I., and Krueger, A., 1999, Early evolution of a stratospheric volcanic eruption cloud as observed with TOMS and AVHRR: Journal of Geophysical Research D: Atmospheres, v. 104, no. D4, p. 4037-4050, https://doi.org/10.1029/1998JD200073.","productDescription":"14 p.","startPage":"4037","endPage":"4050","numberOfPages":"14","costCenters":[{"id":222,"text":"Earth Resources Observation and Science (EROS) Center","active":true,"usgs":true}],"links":[{"id":229119,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"104","issue":"D4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0486e4b0c8380cd50a2e","contributors":{"authors":[{"text":"Schneider, D.J.","contributorId":12997,"corporation":false,"usgs":true,"family":"Schneider","given":"D.J.","email":"","affiliations":[],"preferred":false,"id":391410,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Rose, William I. Jr.","contributorId":71556,"corporation":false,"usgs":true,"family":"Rose","given":"William","suffix":"Jr.","email":"","middleInitial":"I.","affiliations":[],"preferred":false,"id":391412,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Coke, L.R.","contributorId":84934,"corporation":false,"usgs":true,"family":"Coke","given":"L.R.","email":"","affiliations":[],"preferred":false,"id":391415,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Bluth, G.J.S.","contributorId":79258,"corporation":false,"usgs":true,"family":"Bluth","given":"G.J.S.","email":"","affiliations":[],"preferred":false,"id":391414,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Sprod, I.E.","contributorId":17391,"corporation":false,"usgs":true,"family":"Sprod","given":"I.E.","email":"","affiliations":[],"preferred":false,"id":391411,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Krueger, A.J.","contributorId":73764,"corporation":false,"usgs":true,"family":"Krueger","given":"A.J.","email":"","affiliations":[],"preferred":false,"id":391413,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70021719,"text":"70021719 - 1999 - Seafloor environments in the Long Island Sound estuarine system","interactions":[],"lastModifiedDate":"2012-03-12T17:19:37","indexId":"70021719","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2667,"text":"Marine Geology","active":true,"publicationSubtype":{"id":10}},"title":"Seafloor environments in the Long Island Sound estuarine system","docAbstract":"Four categories of modern seafloor sedimentary environments have been identified and mapped across the large, glaciated, topographically complex Long Island Sound estuary by means of an extensive regional set of sidescan sonographs, bottom samples, and video-camera observations and supplemental marine-geologic and modeled physical-oceanographic data. (1) Environments of erosion or nondeposition contain sediments which range from boulder fields to gravelly coarse-to-medium sands and appear on the sonographs either as patterns with isolated reflections (caused by outcrops of glacial drift and bedrock) or as patterns of strong backscatter (caused by coarse lag deposits). Areas of erosion or nondeposition were found across the rugged seafloor at the eastern entrance of the Sound and atop bathymetric highs and within constricted depressions in other parts of the basin. (2) Environments of bedload transport contain mostly coarse-to-fine sand with only small amounts of mud and are depicted by sonograph patterns of sand ribbons and sand waves. Areas of bedload transport were found primarily in the eastern Sound where bottom currents have sculptured the surface of a Holocene marine delta and are moving these sediments toward the WSW into the estuary. (3) Environments of sediment sorting and reworking comprise variable amounts of fine sand and mud and are characterized either by patterns of moderate backscatter or by patterns with patches of moderate-to-weak backscatter that reflect a combination of erosion and deposition. Areas of sediment sorting and reworking were found around the periphery of the zone of bedload transport in the eastern Sound and along the southern nearshore margin. They also are located atop low knolls, on the flanks of shoal complexes, and within segments of the axial depression in the western Sound. (4) Environments of deposition are blanketed by muds and muddy fine sands that produce patterns of uniformly weak backscatter. Depositional areas occupy broad areas of the basin floor in the western part of the Sound. The regional distribution of seafloor environments reflects fundamental differences in marine-geologic conditions between the eastern and western parts of the Sound. In the funnel-shaped eastern part, a gradient of strong tidal currents coupled with the net nontidal (estuarine) bottom drift produce a westward progression of environments ranging from erosion or nondeposition at the narrow entrance to the Sound, through an extensive area of bedload transport, to a peripheral zone of sediment sorting. In the generally broader western part of the Sound, a weak tidal-current regime combined with the production of particle aggregates by biologic or chemical processes, cause large areas of deposition that are locally interrupted by a patchy distribution of various other environments where the bottom currents are enhanced by and interact with the seafloor topography.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Marine Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0025-3227(98)00129-7","issn":"00253227","usgsCitation":"Knebel, H., Signell, R.P., Rendigs, R., Poppe, L., and List, J.H., 1999, Seafloor environments in the Long Island Sound estuarine system: Marine Geology, v. 155, no. 3-4, p. 277-318, https://doi.org/10.1016/S0025-3227(98)00129-7.","startPage":"277","endPage":"318","numberOfPages":"42","costCenters":[],"links":[{"id":229260,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206264,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0025-3227(98)00129-7"}],"volume":"155","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b882ae4b08c986b31682c","contributors":{"authors":[{"text":"Knebel, H.J.","contributorId":79092,"corporation":false,"usgs":true,"family":"Knebel","given":"H.J.","affiliations":[],"preferred":false,"id":390899,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Signell, R. P.","contributorId":89147,"corporation":false,"usgs":true,"family":"Signell","given":"R.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":390900,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Rendigs, R.R.","contributorId":50506,"corporation":false,"usgs":true,"family":"Rendigs","given":"R.R.","affiliations":[],"preferred":false,"id":390896,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Poppe, L.J.","contributorId":72782,"corporation":false,"usgs":true,"family":"Poppe","given":"L.J.","affiliations":[],"preferred":false,"id":390898,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"List, J. H.","contributorId":70406,"corporation":false,"usgs":true,"family":"List","given":"J.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":390897,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70021790,"text":"70021790 - 1999 - Stratigraphic framework and heavy minerals of the continental shelf of Onslow and Long Bays, North Carolina","interactions":[],"lastModifiedDate":"2013-10-29T11:40:12","indexId":"70021790","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2669,"text":"Marine Georesources and Geotechnology","active":true,"publicationSubtype":{"id":10}},"title":"Stratigraphic framework and heavy minerals of the continental shelf of Onslow and Long Bays, North Carolina","docAbstract":"One hundred fourteen vibracores from the Atlantic continental shelf offshore of southeastern North Carolina were opened, described, and processed over several contract years (years 6-9) of the Minerals Management Service-Association of American State Geologists Continental Margins program. Reports for years 9 and 10 of the program compiled the results of the work and assembled the data for release as an interactive CD-ROM report, respectively. The continental shelf of Onslow and Long Bays consists predominantly of outcropping Cretaceous through late Tertiary geologic units. Nearshore these units are covered and incised by late Tertiary and Quaternary units. From oldest to youngest, formally recognized geologic units mapped as part of this study are the Late Cretaceous Peedee Formation-a muddy, fine- to medium-grained quartz sand with trace amounts of glauconite and phosphate; the Paleocene Beaufort Formation-a muddy, fine- to medium-grained glauconitic quartz sand with locally occurring turritelid-mold biosparrudite; the middle Eocene Castle Hayne Formation-a sandy bryozoan biomicrudite and biosparrudite; the Oligocene River Bend Formation-a sandy molluscan-mold biosparrudite; and the Miocene Pungo River Formation-a medium-grained, poorly sorted slightly shelly phosphatic sand. Informal units include a very widespread, unnamed fine- to very fine grained, well-sorted, dolomitic muddy quartz sand that is biostratigraphically equivalent to the Oligocene River Bend Formation; several large valley-fill lithosomes composed of biomicrudite, biomicrite, and biosparrudite of Plio/Pleistocene age; muddy, shelly sands and silty clays of Pliocene, Pleistocene, or mixed Plio/Pleistocene age; and loose, slightly shelly, medium- to coarse-grained sands assigned a Holocene age. Heavy minerals (SG > 2.96) comprise an average of 0.54 wt% (on a bulk-sample basis) of the sediments in 306 samples derived from the 114 vibracores. Heavy-mineral content ranges from <0.01 to 3.69 wt%. The economic heavy mineral content (EHM = ilmenite + zircon + rutile + aluminosilicates + leucoxene [altered ilmenite] + monazite) of the bulk samples averages 0.26 wt% in a range of <0.01-1.70 wt%. As a percentage of the heavy-mineral concentrate, the average EHM value is 45.78% in a range of 0.27-68.60%. The distribution of heavy minerals offshore of southeastern North Carolina is controlled by the lithostratigraphic framework. The unnamed Oligocene sand unit has the highest heavy-mineral content, averaging 0.86 wt% on a bulk-sample basis. The remaining geologic units and their heavy-mineral content (in decreasing order of abundance) are Beaufort (0.64%), Holocene sand (0.60%), Plio-Pleistocene muddy sand and silty clay (0.59%), Peedee (0.42%), River Bend (0.34%), Plio-Pleistocene carbonate (0.12%), and Castle Hayne (0.08%). The heavy-mineral assemblage is fairly consistent throughout the different units. Significantly smaller percentages of heavy minerals correlate with increased amounts of CaCO3 in the sediments. The sediments analyzed in this study have significantly lower overall heavy-mineral content, as well as lower EHM content than sediments that are known to host commercially important heavy-mineral deposits in the southeastern United States. The potential for economic deposits of heavy minerals in the area of this study, therefore, appears to be limited.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Marine Georesources and Geotechnology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Taylor & Francis Ltd","publisherLocation":"London, United Kingdom","doi":"10.1080/106411999273846","issn":"1064119X","usgsCitation":"Hoffman, C.W., Grosz, A., and Nickerson, J.G., 1999, Stratigraphic framework and heavy minerals of the continental shelf of Onslow and Long Bays, North Carolina: Marine Georesources and Geotechnology, v. 17, no. 2-3, p. 173-184, https://doi.org/10.1080/106411999273846.","startPage":"173","endPage":"184","numberOfPages":"12","costCenters":[],"links":[{"id":229266,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":268184,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1080/106411999273846"}],"volume":"17","issue":"2-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9901e4b08c986b31c1c1","contributors":{"authors":[{"text":"Hoffman, Charles W.","contributorId":101405,"corporation":false,"usgs":true,"family":"Hoffman","given":"Charles","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":391190,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Grosz, Andrew E.","contributorId":55051,"corporation":false,"usgs":true,"family":"Grosz","given":"Andrew E.","affiliations":[],"preferred":false,"id":391189,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Nickerson, John G.","contributorId":30390,"corporation":false,"usgs":true,"family":"Nickerson","given":"John","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":391188,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":21835,"text":"ofr9838 - 1998 - Geology, geochemistry, geophysics, mineral occurrences, and mineral resource assessment for the Commonwealth of Puerto Rico","interactions":[],"lastModifiedDate":"2022-06-27T20:27:23.780018","indexId":"ofr9838","displayToPublicDate":"2001-09-01T00:00:00","publicationYear":"1998","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":"98-38","title":"Geology, geochemistry, geophysics, mineral occurrences, and mineral resource assessment for the Commonwealth of Puerto Rico","docAbstract":"The Commonwealth of Puerto Rico has been investigated over a very long period of time by earth scientists from many disciplines and with diverse objectives in the studies. This publication attempts to apply much of the geologic, geochemical, geophysical, and mineral occurrence information to a single objective focused on producing a mineral resource assessment for the Commonwealth of Puerto Rico. However, the value of this publication lies not within the results of the mineral resource assessment nor within the interactive PDF files which can be viewed on the screen, but within the geologic, geochemical, geophysical, and mineral occurrence digital map coverages and databases which can be used for their own unique applications.\r\n\r\nThe mineral resource assessment of Puerto Rico represents compilation of several decades of mineral investigations and studies. These investigations have been the joint efforts of the U.S. Geological Survey, the Puerto Rico Department of Natural Resources, and the University of Puerto Rico. This report contains not only the mineral-resource assessment, but also much of the scientific evidence upon which the assessment was based.","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ofr9838","issn":"0566-8174","collaboration":"Prepared in cooperation with the Puerto Rico Department of Natural Resources, University of Puerto Rico at Mayaguez","usgsCitation":"1998, Geology, geochemistry, geophysics, mineral occurrences, and mineral resource assessment for the Commonwealth of Puerto Rico: U.S. Geological Survey Open-File Report 98-38, HTML Document; CD-ROM, https://doi.org/10.3133/ofr9838.","productDescription":"HTML Document; CD-ROM","onlineOnly":"N","additionalOnlineFiles":"Y","costCenters":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"links":[{"id":153597,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"},{"id":13388,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/of/1998/of98-038/","linkFileType":{"id":5,"text":"html"}},{"id":402559,"rank":2,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_34894.htm","linkFileType":{"id":5,"text":"html"}}],"country":"United States","state":"Puerto Rico","geographicExtents":"{\"type\":\"FeatureCollection\",\"features\":[{\"type\":\"Feature\",\"geometry\":{\"type\":\"MultiPolygon\",\"coordinates\":[[[[-65.3277,18.295843],[-65.337451,18.308308],[-65.327318,18.323666],[-65.342068,18.34529],[-65.335701,18.349535],[-65.329334,18.341955],[-65.321754,18.338316],[-65.309833,18.337973],[-65.304409,18.332054],[-65.298328,18.330529],[-65.255933,18.342117],[-65.221568,18.320959],[-65.222853,18.310464],[-65.249857,18.296691],[-65.260282,18.290823],[-65.283269,18.280214],[-65.3277,18.295843]]],[[[-67.89174,18.11397],[-67.887099,18.112574],[-67.87643,18.114157],[-67.869804,18.118851],[-67.861548,18.122144],[-67.848245,18.10832],[-67.843202,18.094858],[-67.843615,18.085099],[-67.845293,18.081938],[-67.853098,18.078195],[-67.865598,18.06544],[-67.871462,18.0578],[-67.895921,18.052342],[-67.904431,18.05913],[-67.918778,18.063116],[-67.927841,18.068572],[-67.940799,18.079716],[-67.934479,18.111306],[-67.932185,18.113221],[-67.91088,18.119668],[-67.89174,18.11397]]],[[[-65.308717,18.145172],[-65.302295,18.141089],[-65.294896,18.14283],[-65.287962,18.148097],[-65.275165,18.13443],[-65.276214,18.131936],[-65.283248,18.132999],[-65.296036,18.12799],[-65.322794,18.126589],[-65.327184,18.124106],[-65.338506,18.112439],[-65.342037,18.11138],[-65.350493,18.111914],[-65.364733,18.120377],[-65.397837,18.110873],[-65.399791,18.108832],[-65.411767,18.106211],[-65.423765,18.097764],[-65.426311,18.093749],[-65.45138,18.086096],[-65.45681,18.087778],[-65.465849,18.087715],[-65.468768,18.092643],[-65.47979,18.096352],[-65.507265,18.091646],[-65.524209,18.081977],[-65.542087,18.081177],[-65.558646,18.08566],[-65.569305,18.091616],[-65.570628,18.097325],[-65.57686,18.103224],[-65.575579,18.115669],[-65.546199,18.119329],[-65.511712,18.13284],[-65.489829,18.135912],[-65.46791,18.143767],[-65.437058,18.15766],[-65.399517,18.161935],[-65.371373,18.157517],[-65.334289,18.147761],[-65.313476,18.144296],[-65.308717,18.145172]]],[[[-66.438813,18.485713],[-66.420921,18.488639],[-66.410344,18.489886],[-66.394287,18.489748],[-66.377286,18.488044],[-66.37282,18.487726],[-66.349647,18.486335],[-66.337728,18.48562],[-66.315477,18.474724],[-66.31503,18.47468],[-66.291225,18.472347],[-66.283675,18.472203],[-66.276599,18.478129],[-66.269799,18.480281],[-66.258015,18.476906],[-66.251547,18.472464],[-66.241797,18.46874],[-66.220148,18.466],[-66.199032,18.466163],[-66.192664,18.466212],[-66.183886,18.460506],[-66.179218,18.455305],[-66.172315,18.451462],[-66.159796,18.451706],[-66.153037,18.454457],[-66.14395,18.459761],[-66.139572,18.462317],[-66.139451,18.462387],[-66.139443,18.462315],[-66.138532,18.453305],[-66.133085,18.445881],[-66.127938,18.444632],[-66.125198,18.451209],[-66.124284,18.456324],[-66.123188,18.45943],[-66.123343,18.460363],[-66.125015,18.470435],[-66.118338,18.469581],[-66.092098,18.466535],[-66.083254,18.462022],[-66.073987,18.4581],[-66.043272,18.453655],[-66.03944,18.454441],[-66.036559,18.450216],[-66.036491,18.450117],[-66.023221,18.443875],[-66.006523,18.444347],[-65.99718,18.449895],[-65.992935,18.457489],[-65.992793,18.458102],[-65.992349,18.460024],[-65.99079,18.460419],[-65.958492,18.451354],[-65.92567,18.444881],[-65.916843,18.444619],[-65.907756,18.446893],[-65.904988,18.450926],[-65.878683,18.438322],[-65.838825,18.431865],[-65.831476,18.426849],[-65.828457,18.423543],[-65.816691,18.410663],[-65.794556,18.402845],[-65.787666,18.402544],[-65.774937,18.413951],[-65.77053,18.41294],[-65.769749,18.409473],[-65.771695,18.406277],[-65.750455,18.385208],[-65.750179,18.38505],[-65.742154,18.380459],[-65.733567,18.382211],[-65.699069,18.368156],[-65.669636,18.362102],[-65.668845,18.361939],[-65.634431,18.369835],[-65.627246,18.376436],[-65.626527,18.381728],[-65.624975,18.386553],[-65.622761,18.387771],[-65.618229,18.386496],[-65.614891,18.382473],[-65.619068,18.367755],[-65.628198,18.353711],[-65.63419,18.338965],[-65.628047,18.328252],[-65.626456,18.298982],[-65.634389,18.292349],[-65.635826,18.288271],[-65.634893,18.283923],[-65.630833,18.264989],[-65.623111,18.248012],[-65.597618,18.234289],[-65.589947,18.228225],[-65.593795,18.224059],[-65.615981,18.227389],[-65.626731,18.235484],[-65.638181,18.229121],[-65.637565,18.224444],[-65.628414,18.205149],[-65.635281,18.199975],[-65.639688,18.205656],[-65.662185,18.207018],[-65.664127,18.207136],[-65.690749,18.19499],[-65.694515,18.187011],[-65.691021,18.178998],[-65.695856,18.179324],[-65.710895,18.186963],[-65.712533,18.189146],[-65.717999,18.190176],[-65.728471,18.185588],[-65.734664,18.180368],[-65.738834,18.174066],[-65.739125,18.173453],[-65.743632,18.163957],[-65.758728,18.156601],[-65.766919,18.148424],[-65.777584,18.129239],[-65.796711,18.083746],[-65.796289,18.079835],[-65.794686,18.078607],[-65.795028,18.073561],[-65.796711,18.069842],[-65.801831,18.058527],[-65.809174,18.056818],[-65.817107,18.063378],[-65.825848,18.057482],[-65.83109,18.050664],[-65.834274,18.038988],[-65.832429,18.014916],[-65.839591,18.015077],[-65.850913,18.011954],[-65.870335,18.006597],[-65.875122,18.002826],[-65.884937,17.988521],[-65.896102,17.99026],[-65.905319,17.983974],[-65.910537,17.981855],[-65.924738,17.976087],[-65.976611,17.967669],[-65.98455,17.969411],[-65.985358,17.971854],[-65.995185,17.978989],[-66.007731,17.980541],[-66.017308,17.979583],[-66.019539,17.978354],[-66.024,17.975896],[-66.046585,17.954853],[-66.049033,17.954561],[-66.058217,17.959238],[-66.068678,17.966335],[-66.069979,17.966357],[-66.08141,17.966552],[-66.116194,17.949141],[-66.127009,17.946953],[-66.140661,17.94102],[-66.147912,17.933963],[-66.155387,17.929406],[-66.159742,17.928613],[-66.161232,17.931747],[-66.175626,17.933565],[-66.186914,17.935363],[-66.189726,17.933936],[-66.200174,17.929515],[-66.206961,17.932268],[-66.213374,17.944614],[-66.202655,17.944753],[-66.185554,17.940997],[-66.179548,17.943727],[-66.174839,17.948214],[-66.176814,17.950438],[-66.206207,17.96305],[-66.206807,17.963307],[-66.215355,17.959376],[-66.218081,17.95729],[-66.231519,17.943912],[-66.229181,17.934651],[-66.232013,17.931154],[-66.252737,17.934574],[-66.260684,17.936083],[-66.270905,17.947098],[-66.275651,17.94826],[-66.290782,17.946491],[-66.297679,17.959148],[-66.31695,17.976683],[-66.323659,17.978536],[-66.338152,17.976492],[-66.33839,17.976458],[-66.362511,17.968231],[-66.365098,17.964832],[-66.368777,17.957717],[-66.371591,17.951469],[-66.385059,17.939004],[-66.391227,17.945819],[-66.398945,17.950925],[-66.412131,17.957286],[-66.445481,17.979379],[-66.450368,17.983226],[-66.454888,17.986784],[-66.461342,17.990273],[-66.491396,17.990262],[-66.510143,17.985618],[-66.540537,17.975476],[-66.583233,17.961229],[-66.589658,17.969386],[-66.594392,17.970682],[-66.605035,17.969015],[-66.623788,17.98105],[-66.631944,17.982746],[-66.645651,17.98026],[-66.657797,17.974605],[-66.664391,17.968259],[-66.672819,17.966451],[-66.699115,17.977568],[-66.709856,17.982109],[-66.713394,17.987763],[-66.716957,17.990344],[-66.731118,17.991658],[-66.746248,17.990349],[-66.750427,17.995443],[-66.753964,17.99959],[-66.755341,18.001203],[-66.764491,18.006317],[-66.770307,18.005955],[-66.799656,17.99245],[-66.806866,17.983786],[-66.807924,17.979606],[-66.806903,17.976046],[-66.805683,17.975052],[-66.795106,17.977438],[-66.789302,17.980793],[-66.784953,17.978326],[-66.787245,17.972914],[-66.80827,17.965635],[-66.8224,17.954499],[-66.838584,17.949931],[-66.852288,17.955004],[-66.856474,17.956553],[-66.859471,17.954316],[-66.862545,17.952022],[-66.871697,17.952707],[-66.88344,17.952526],[-66.899639,17.948298],[-66.904585,17.950527],[-66.906532,17.955356],[-66.906276,17.963368],[-66.924529,17.972808],[-66.928651,17.970204],[-66.930414,17.963127],[-66.916127,17.959102],[-66.909483,17.952559],[-66.909359,17.94988],[-66.912522,17.947446],[-66.930313,17.943389],[-66.932636,17.939998],[-66.931581,17.9369],[-66.919298,17.932062],[-66.923826,17.926923],[-66.927261,17.926875],[-66.959998,17.940216],[-66.980516,17.951648],[-66.98105,17.952505],[-66.982669,17.9551],[-66.982206,17.961192],[-66.987287,17.970663],[-66.996738,17.972899],[-67.003972,17.970799],[-67.014744,17.968468],[-67.024522,17.970722],[-67.062478,17.973819],[-67.076534,17.967759],[-67.089827,17.951418],[-67.101468,17.946621],[-67.109985,17.945806],[-67.109986,17.945806],[-67.128251,17.948153],[-67.133733,17.951919],[-67.167031,17.963073],[-67.178566,17.964792],[-67.183508,17.962706],[-67.188717,17.950989],[-67.187474,17.946252],[-67.183694,17.937982],[-67.183457,17.931135],[-67.194785,17.932826],[-67.196924,17.935651],[-67.197273,17.937461],[-67.197517,17.941514],[-67.197668,17.943549],[-67.198988,17.94782],[-67.200973,17.949896],[-67.210034,17.953595],[-67.212101,17.956027],[-67.21433,17.962436],[-67.215271,17.983464],[-67.211973,17.992993],[-67.207694,17.998019],[-67.177893,18.008882],[-67.174299,18.011149],[-67.172397,18.014906],[-67.172138,18.021422],[-67.173761,18.024548],[-67.193269,18.03185],[-67.209887,18.035439],[-67.196694,18.066491],[-67.190656,18.064269],[-67.184589,18.06775],[-67.183938,18.069914],[-67.186465,18.074195],[-67.192999,18.076877],[-67.198212,18.076828],[-67.199314,18.091135],[-67.19529,18.096149],[-67.183921,18.103683],[-67.182182,18.108507],[-67.176554,18.151046],[-67.178618,18.159318],[-67.180822,18.168055],[-67.180701,18.168182],[-67.155185,18.195001],[-67.152665,18.203493],[-67.158001,18.216719],[-67.173,18.230666],[-67.175429,18.248008],[-67.187843,18.266671],[-67.187873,18.266874],[-67.189971,18.281015],[-67.196056,18.290443],[-67.209963,18.294974],[-67.225403,18.296648],[-67.226081,18.296722],[-67.235137,18.299935],[-67.267484,18.353149],[-67.27135,18.362329],[-67.268259,18.366989],[-67.260671,18.370197],[-67.23909,18.375318],[-67.226744,18.378247],[-67.216998,18.382078],[-67.202167,18.389908],[-67.160144,18.415587],[-67.159608,18.415915],[-67.156599,18.418983],[-67.155245,18.424401],[-67.156619,18.439562],[-67.161746,18.453462],[-67.169011,18.466352],[-67.169016,18.478488],[-67.164144,18.487396],[-67.14283,18.505485],[-67.138249,18.507776],[-67.125655,18.511706],[-67.103468,18.514523],[-67.093752,18.515757],[-67.07929,18.513256],[-67.020276,18.510603],[-66.988958,18.497724],[-66.95954,18.489878],[-66.957733,18.489129],[-66.957517,18.489171],[-66.944636,18.491693],[-66.906872,18.483556],[-66.90143,18.484552],[-66.867386,18.490785],[-66.849673,18.490745],[-66.83694,18.487659],[-66.836635,18.487701],[-66.79932,18.492775],[-66.780311,18.491411],[-66.764893,18.484097],[-66.749301,18.476701],[-66.742067,18.474681],[-66.733986,18.473457],[-66.710743,18.472611],[-66.683719,18.481367],[-66.679876,18.484944],[-66.664364,18.487809],[-66.645839,18.488777],[-66.624618,18.494199],[-66.586778,18.484948],[-66.584074,18.484287],[-66.565241,18.485523],[-66.562916,18.48845],[-66.563485,18.490512],[-66.558503,18.489987],[-66.53484,18.481253],[-66.533487,18.481663],[-66.529476,18.482877],[-66.511609,18.476848],[-66.470292,18.46907],[-66.456486,18.46892],[-66.449184,18.470991],[-66.441852,18.479751],[-66.439961,18.485525],[-66.438813,18.485713]]]]},\"properties\":{\"name\":\"Puerto Rico\",\"nation\":\"USA \"}}]}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ac9e4b07f02db67c6c8","contributors":{"editors":[{"text":"Bawiec, Walter J.","contributorId":83909,"corporation":false,"usgs":true,"family":"Bawiec","given":"Walter","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":504023,"contributorType":{"id":2,"text":"Editors"},"rank":1}]}} ,{"id":23749,"text":"ofr98466 - 1998 - Comparative geology and geochemistry of sedimentary-rock-hosted (Carlin Type) gold deposits in the People's Republic of China and in Nevada, USA","interactions":[],"lastModifiedDate":"2012-02-02T00:08:15","indexId":"ofr98466","displayToPublicDate":"1999-05-01T00:00:00","publicationYear":"1998","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":"98-466","title":"Comparative geology and geochemistry of sedimentary-rock-hosted (Carlin Type) gold deposits in the People's Republic of China and in Nevada, USA","docAbstract":"Sedimentary-rock-hosted (Carlin-type) gold deposits have been considered economically significant and geologically distinct since the early 1960's. This report consists of a nine-part text and an interactive database. This small database is to help Western companies get more information about these gold deposits in China, and to help geologists who are interested in world Carlin-type deposits conduct research on them. Because of their economic significance and geological distinctiveness, these deposits have caught the interest of economic geologists all over the world since the early 1960's. Similar deposits have been discovered in China, Australia, Dominican Republic, Spain, and Russia besides Nevada. Perhaps most significant are the 165 Carlin-type gold deposits that were found in southwest China during the past 15 years. Of these, at least 19 deposits have proven to be of substantial tonnage, making China the second leading country to exploit such deposits. With the increasing interest in Chinese Carlin-type gold deposits, some western companies and geologists desire to get more information about these Chinese deposits. This seems to have been very difficult because the literature was in Chinese. It is estimated that several hundred scientific publications (including papers, books, and technical reports) have been published. This database of Chinese Carlin-type Gold deposits is built on the documentation published during the most recent 10 years and includes six subjects, which consist of 165 records and 30 fields. A new Proterozoic-age sedimentary-rock-hosted gold deposit in northeastern P.R. China also is described. Note that for the old version 1.1 on the CD-ROM, the latitude and longitude locations of the mineral occurrences have been estimated from sketch maps and journal articles and are not intended for digital analysis. One of the improvements in this version 1.2 is the accuracy of geographic data. Version 1.3 updates to the database and includes maps and photos of deposits, deposit information and a geochemical model. See the version history for details.","language":"ENGLISH","publisher":"U.S. Geological Survey,","doi":"10.3133/ofr98466","issn":"0094-9140","usgsCitation":"Li, Z., and Peters, S., 1998, Comparative geology and geochemistry of sedimentary-rock-hosted (Carlin Type) gold deposits in the People's Republic of China and in Nevada, USA (Version 1.3, 2001): U.S. Geological Survey Open-File Report 98-466, v, 160 p. :ill., maps ;28 cm., https://doi.org/10.3133/ofr98466.","productDescription":"v, 160 p. :ill., maps ;28 cm.","additionalOnlineFiles":"Y","costCenters":[],"links":[{"id":156785,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1998/0466/report-thumb.jpg"},{"id":9136,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/of/1998/of98-466/","linkFileType":{"id":5,"text":"html"}},{"id":52982,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1998/0466/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"edition":"Version 1.3, 2001","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b24e4b07f02db6ae511","contributors":{"authors":[{"text":"Li, Zhiping","contributorId":98762,"corporation":false,"usgs":true,"family":"Li","given":"Zhiping","email":"","affiliations":[],"preferred":false,"id":190651,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Peters, Stephen G. speters@usgs.gov","contributorId":2793,"corporation":false,"usgs":true,"family":"Peters","given":"Stephen G.","email":"speters@usgs.gov","affiliations":[{"id":596,"text":"U.S. Geological Survey National Center","active":false,"usgs":true}],"preferred":false,"id":190650,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":32152,"text":"ofr98343 - 1998 - Surficial geology of Shaver Hollow, Shenandoah National Park","interactions":[],"lastModifiedDate":"2015-11-12T13:18:13","indexId":"ofr98343","displayToPublicDate":"1999-05-01T00:00:00","publicationYear":"1998","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":"98-343","title":"Surficial geology of Shaver Hollow, Shenandoah National Park","docAbstract":"At the request of Shenandoah National Park and the Department of Environmental Sciences at the University of Virginia, the US Geological Survey has completed an examination and map of the surficial deposits in Shaver Hollow. The work was carried out as part of the US Geological Survey - National Park Service cooperative agreement implemented in 1994. Shaver Hollow is a small, well defined drainage basin on the west slope of the Blue Ridge about 6.5 miles south of Thornton Gap and can be reached by trail from mile 37.9 on the Skyline Drive. The hollow is drained by the North Fork of Dry Run, and the watershed within the Shenandoah National park is only 2 square miles in area. The area has been the site of extensive investigations by faculty and students at the University of Virginia and by NPS scientists and investigators studying the interaction of atmosphere chemistry, water composition, and the biota of the hollow (Furman and others, written communication, 1997). Modeling of the chemistry of Dry Run surface water, based on atmospheric, biologic, and geologic data, has been attempted with limited success. Better understanding of the surficial deposits and the interaction of streams and springs with near surface materials is needed before more sophisticated models can be devised. Although the bedrock lithology was mapped at a small scale (1:62,000-scale; Gathright, 1976) no examination of the surficial deposits of the hollow was made. The description of deposits contained herein is based on field observations carried out in September - November, 1996. Also included with this report is a 1/12,000-scale map of the surficial geology of Shaver Hollow (figure 1).
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ofr98343","usgsCitation":"Morgan, B.A., 1998, Surficial geology of Shaver Hollow, Shenandoah National Park: U.S. Geological Survey Open-File Report 98-343, Report: 13 p.; Plate: 16.04 x 21.46 inches, https://doi.org/10.3133/ofr98343.","productDescription":"Report: 13 p.; Plate: 16.04 x 21.46 inches","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":60270,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1998/0343/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":311134,"rank":301,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/of/1998/0343/figure-1.pdf","text":"Figure 1","linkFileType":{"id":1,"text":"pdf"}},{"id":162983,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1998/0343/report-thumb.jpg"}],"scale":"2000","country":"United States","state":"Virginia","otherGeospatial":"Shaver Hollow, Shenandoah National Park","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -78.651123046875,\n 38.28023506734758\n ],\n [\n -78.651123046875,\n 38.62008939987629\n ],\n [\n -78.26797485351562,\n 38.62008939987629\n ],\n [\n -78.26797485351562,\n 38.28023506734758\n ],\n [\n -78.651123046875,\n 38.28023506734758\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4ae2e4b07f02db688b31","contributors":{"authors":[{"text":"Morgan, Benjamin A.","contributorId":32158,"corporation":false,"usgs":true,"family":"Morgan","given":"Benjamin","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":207847,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":66872,"text":"i2557 - 1998 - Geologic map of the Dao, Harmakhis, and Reull Valles region of Mars","interactions":[],"lastModifiedDate":"2023-06-28T11:23:32.175922","indexId":"i2557","displayToPublicDate":"1998-12-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":320,"text":"IMAP","code":"I","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"2557","title":"Geologic map of the Dao, Harmakhis, and Reull Valles region of Mars","docAbstract":"The geology for this map was compiled using Viking Orbiter images on 1:500,000- scale photomosaics of the Mars Transverse Mercator quadrangles -40262, -40267, and -40272. This map represents a detailed extension of regional geologic mapping of the east Hellas rim (Crown and others 1990, 1992) and is published at 1:1,000,000 scale. The map area is on the east rim of one of the largest impact structures in the Solar System, the ~2,000-km-diameter Hellas basin (fig. 1). Channeled plains, with Dao, Harmakhis, and Reull Valles as the primary drainage features, dominate much of the surface within the map area. Dao Vallis is the downstream extension of Niger Vallis, which originates on the south flank of Hadriaca Patera, north of the map area. Harmakhis Vallis and Reull Vallis appear to intersect near latitutude 38°30' S., longitude 264°30'; Harmakhis Vallis trends southwest and Reull Vallis trends southeast from the area of intersection. The source area for these major outflow channels is at the intersection of two principal rings of multiring impact basins (Potter, 1976; Schultz and Frey, 1990; fig. 1). Hellas basin is centered southwest of the map area, and the proposed Hesperia basin is centered northeast of the map area (Schultz and Frey, 1990). The eastern part of the map area contains extensive remnants of ancient mountains and crater rim materials, along with large mesa-like features. Landforms over the entire map area appear to have been modified by multiple erosional events including downslope movement, eolian, and fluvial processes. The purpose of mapping the geology of the Dao, Harmakhis, and Reull Valles region of Mars is to refine stratigraphic and geomorphologic relations among the geologic units in thearea in order to better understand the nature of, relative timing of, and interactions among martian highland surface processes.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/i2557","isbn":"060790223X","usgsCitation":"Price, K.H., 1998, Geologic map of the Dao, Harmakhis, and Reull Valles region of Mars: U.S. Geological Survey IMAP 2557, HTML Document, https://doi.org/10.3133/i2557.","productDescription":"HTML Document","costCenters":[],"links":[{"id":438903,"rank":3,"type":{"id":30,"text":"Data Release"},"url":"https://doi.org/10.5066/P9NN56QJ","text":"USGS data release","linkHelpText":"Geologic map of the Dao, Harmakhis, and Reull Valles region of Mars"},{"id":189886,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"},{"id":6125,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/imap/i2557/","linkFileType":{"id":5,"text":"html"}}],"scale":"1004000","otherGeospatial":"Mars","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b09e4b07f02db69bcdd","contributors":{"authors":[{"text":"Price, Katherine H.","contributorId":22040,"corporation":false,"usgs":true,"family":"Price","given":"Katherine","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":275206,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":4860,"text":"ds50 - 1998 - Teaching earth science","interactions":[],"lastModifiedDate":"2018-01-26T11:17:52","indexId":"ds50","displayToPublicDate":"1998-08-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":310,"text":"Data Series","code":"DS","onlineIssn":"2327-638X","printIssn":"2327-0271","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"50","title":"Teaching earth science","docAbstract":"This CD-ROM contains 17 teaching tools: 16 interactive HyperCard 'stacks' and a printable model. They are separated into the following categories: Geologic Processes, Earthquakes and Faulting, and Map Projections and Globes. A 'navigation' stack, Earth Science, is provided as a 'launching' place from which to access all of the other stacks. You can also open the HyperCard Stacks folder and launch any of the 16 stacks yourself. In addition, a 17th tool, Earth and Tectonic Globes, is provided as a printable document. Each of the tools can be copied onto a 1.4-MB floppy disk and distributed freely.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/ds50","isbn":"0607898941","usgsCitation":"1998, Teaching earth science: U.S. Geological Survey Data Series 50, 1 computer laser optical disc, https://doi.org/10.3133/ds50.","productDescription":"1 computer laser optical disc","costCenters":[],"links":[{"id":139958,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"},{"id":115723,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://pubs.usgs.gov/dds/dds-50/","linkFileType":{"id":5,"text":"html"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4adce4b07f02db68633b","contributors":{"editors":[{"text":"Alpha, Tau Rho","contributorId":63371,"corporation":false,"usgs":true,"family":"Alpha","given":"Tau","email":"","middleInitial":"Rho","affiliations":[],"preferred":false,"id":725891,"contributorType":{"id":2,"text":"Editors"},"rank":1},{"text":"Diggles, Michael F. 0000-0002-9946-0247 mdiggles@usgs.gov","orcid":"https://orcid.org/0000-0002-9946-0247","contributorId":810,"corporation":false,"usgs":true,"family":"Diggles","given":"Michael","email":"mdiggles@usgs.gov","middleInitial":"F.","affiliations":[{"id":501,"text":"Office of Science Quality and Integrity","active":true,"usgs":true},{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true},{"id":5053,"text":"IPDS Training","active":true,"usgs":true},{"id":5066,"text":"Office of the Director USGS","active":true,"usgs":true}],"preferred":true,"id":725892,"contributorType":{"id":2,"text":"Editors"},"rank":2}]}} ,{"id":3483,"text":"cir1137 - 1998 - Hydrology of Central Florida Lakes - A Primer","interactions":[{"subject":{"id":24469,"text":"ofr96412 - 1996 - Hydrology of central Florida lakes, a primer","indexId":"ofr96412","publicationYear":"1996","noYear":false,"title":"Hydrology of central Florida lakes, a primer"},"predicate":"SUPERSEDED_BY","object":{"id":3483,"text":"cir1137 - 1998 - Hydrology of Central Florida Lakes - A Primer","indexId":"cir1137","publicationYear":"1998","noYear":false,"title":"Hydrology of Central Florida Lakes - A Primer"},"id":1}],"lastModifiedDate":"2012-02-02T00:05:38","indexId":"cir1137","displayToPublicDate":"1998-06-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":307,"text":"Circular","code":"CIR","onlineIssn":"2330-5703","printIssn":"1067-084X","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"1137","title":"Hydrology of Central Florida Lakes - A Primer","docAbstract":"INTRODUCTION\r\n\r\nLakes are among the most valued natural resources of central Florida. The landscape of central Florida is riddled with lakeswhen viewed from the air, it almost seems there is more water than land. Florida has more naturally formed lakes than other southeastern States, where many lakes are created by building dams across streams. The abundance of lakes on the Florida peninsula is a result of the geology and geologic history of the State. An estimated 7,800 lakes in Florida are greater than 1 acre in surface area. Of these, 35 percent are located in just four counties (fig. 1): Lake, Orange, Osceola, and Polk (Hughes, 1974b). Lakes add to the aesthetic and commercial value of the area and are used by many residents and visitors for fishing, boating, swimming, and other types of outdoor recreation. Lakes also are used for other purposes such as irrigation, flood control, water supply, and navigation. Residents and visitors commonly ask questions such as Whyare there so many lakes here?, Why is my lake drying up (or flooding)?, or Is my lake spring-fed? These questions indicate that the basic hydrology of lakes and the interaction of lakes with ground water and surface water are not well understood by the general population.\r\n\r\nBecause of the importance of lakes to residents of central Florida and the many questions and misconceptions about lakes, this primer was prepared by the U.S. Geological Survey (USGS) in cooperation with the St. Johns River Water Management District and the South Florida Water Management District. The USGS has been collecting hydrologic data in central Florida since the 1920s, obtaining valuable information that has been used to better understand the hydrology of the water resources of central Florida, including lakes. In addition to data collection, as of 1994, the USGS had published 66 reports and maps on central Florida lakes (Garcia and Hoy, 1995).\r\n\r\nThe main purpose of this primer is to describe the hydrology of lakes in central Florida, the interactions between lakes and ground- and surface-waters, and to describe how these interactions affect lake water levels. Included are descriptions of the basic geology and geomorphology of central Florida, origins of central Florida lakes, factors that affect lake water levels, lake water quality, and common methods of improving water quality. The geographic area discussed in this primer is approximate (fig. 1) and includes west and east-central Florida, extending from the Gulf of Mexico to the Atlantic Ocean coastlines, northward into Marion, Putnam, and Flagler Counties, and southward to Lake Okeechobee. The information presented here was obtained from the many publications available on lakes in central Florida, as well as from publications on Florida geology, hydrology, and primers on ground water, surface water, and water quality. Many publications are available that provide more detailed information on lake water quality, and this primer is not intended as an extensive treatise on that subject. The reader is referred to the reference section of this primer for sources of more detailed information on lake water quality. Lakes discussed in this report are identified in figure 2. Technical terms used in the report are shown in bold italics and are defined in the glossary.\r\n\r\nThe classification of some water bodies as lakes is highly subjective. What one individual considers a lake another might consider a pond. Generally, any water- filled depression or group of depressions in the land surface could be considered a lake. Lakes differ from swamps or wetlands in the type and amount of vegetation, water depth, and some water-quality characteristics. Lakes typically have emergent vegetation along the shoreline with a large expanse of open water in the center. Swamps or wetlands, on the other hand, are characterized by a water surface interrupted by the emergence of many varieties of plant life, from saw grasses to cypress trees.\r\n\r\nLakes may be na","language":"ENGLISH","publisher":"Geological Survey (U.S.)","doi":"10.3133/cir1137","isbn":"0607885610","collaboration":"Prepared in cooperation with the St. Johns River Water Management District and South Florida Water Management District","usgsCitation":"Schiffer, D.M., 1998, Hydrology of Central Florida Lakes - A Primer: U.S. Geological Survey Circular 1137, vi, 38 p., https://doi.org/10.3133/cir1137.","productDescription":"vi, 38 p.","costCenters":[{"id":595,"text":"U.S. Geological Survey","active":false,"usgs":true}],"links":[{"id":84,"rank":100,"type":{"id":15,"text":"Index Page"},"url":"https://fl.water.usgs.gov/Abstracts/c1137_schiffer.html","linkFileType":{"id":5,"text":"html"}},{"id":139443,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/usgs_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a17e4b07f02db6049b2","contributors":{"authors":[{"text":"Schiffer, Donna M. schiffer@usgs.gov","contributorId":2138,"corporation":false,"usgs":true,"family":"Schiffer","given":"Donna","email":"schiffer@usgs.gov","middleInitial":"M.","affiliations":[],"preferred":true,"id":147010,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70020702,"text":"70020702 - 1998 - Mapping the Gulf of Maine with side-scan sonar: A new bottom-type classification for complex seafloors","interactions":[],"lastModifiedDate":"2012-03-12T17:20:18","indexId":"70020702","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2220,"text":"Journal of Coastal Research","active":true,"publicationSubtype":{"id":10}},"title":"Mapping the Gulf of Maine with side-scan sonar: A new bottom-type classification for complex seafloors","docAbstract":"The bedrock-framed seafloor in the northwestern Gulf of Maine is characterized by extreme changes in bathymetric relief and covered with a wide variety of surficial materials. Traditional methods of mapping cannot accurately represent the great heterogeneity of such a glaciated region. A new mapping scheme for complex seafloors, based primarily on the interpretation of side-scan sonar imagery, utilizes four easily recognized units: rock, gravel, sand and mud. In many places, however, the seafloor exhibits a complicated mixture or extremely 'patchy' distribution of the four basic units, which are too small to map individually. Twelve composite units, each a two-component mixture of the basic units, were established to represent this patchiness at a small scale (1:100,000). Using a geographic information system, these and all other available data (seismic profiles, grab samples, submersible dives and cores) were referenced to a common geographic base, superimposed on bathymetric contours and then integrated into surficial geologic maps of the regional inner continental shelf. This digital representation of the seafloor comprises a multidimensional, interactive model complete with explicit attributes (depth, bottom type) that allow for detailed analysis of marine environments.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Coastal Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"07490208","usgsCitation":"Barnhardt, W., Kelley, J.T., Dickson, S., and Belknap, D.F., 1998, Mapping the Gulf of Maine with side-scan sonar: A new bottom-type classification for complex seafloors: Journal of Coastal Research, v. 14, no. 2, p. 646-659.","startPage":"646","endPage":"659","numberOfPages":"14","costCenters":[],"links":[{"id":231386,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"14","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5079e4b0c8380cd6b6f0","contributors":{"authors":[{"text":"Barnhardt, W. A.","contributorId":86449,"corporation":false,"usgs":true,"family":"Barnhardt","given":"W. A.","affiliations":[],"preferred":false,"id":387191,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kelley, J. T.","contributorId":34197,"corporation":false,"usgs":true,"family":"Kelley","given":"J.","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":387189,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dickson, S.M.","contributorId":74905,"corporation":false,"usgs":true,"family":"Dickson","given":"S.M.","email":"","affiliations":[],"preferred":false,"id":387190,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Belknap, D. F.","contributorId":96739,"corporation":false,"usgs":true,"family":"Belknap","given":"D.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":387192,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70019705,"text":"70019705 - 1997 - Analysis of borehole televiewer measurements in the Vorotilov drillhole, Russia - First results","interactions":[],"lastModifiedDate":"2025-08-14T16:37:58.927983","indexId":"70019705","displayToPublicDate":"1998-06-25T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3525,"text":"Tectonophysics","active":true,"publicationSubtype":{"id":10}},"title":"Analysis of borehole televiewer measurements in the Vorotilov drillhole, Russia - First results","docAbstract":"In the Eurasian part of the World Stress Map almost the whole region east of the Tornquist-Teisseyre line is terra incognita. The closure of this information gap is of fundamental importance to the understanding of the geodynamics of the Eurasian continent. A detailed analysis of stress-induced wellbore breakouts has been performed over a 4.1-km-long depth interval in the Vorotilov drillhole (VGS). The borehole is located in the central part of the Russian platform, right in the center of the Vorotilov meteorite impact crater 60 km to the NNE of the city of Nizni Novgorod. An ultrasonic borehole televiewer (BHTV) was used to obtain high-resolution acoustical images from the borehole wall. With an interactive system for analyzing BHTV data the azimuth and shape of borehole breakouts occurring in the depth range of 1.3–4.8 km were analyzed. A statistical analysis of the resulting orientation profile of the breakout azimuths yields an overall direction of the maximum horizontal principal stress SH of N 137°E ± 15°. Variations of breakout orientation with depth ranging from a few degrees up to more than 90° are seen on various depth scales.
The observed stress direction of N 137°E agrees very well with the average SH orientation of N 145°E in Central Europe. If this measurement is taken as representative for the Russian platform, the stress field in Russia is only slightly rotated in comparison to Central Europe. This can possibly be interpreted as indicative for the stress field to be governed by broad scale tectonic forces, such as a strong contribution from the forces exerted by the collision zone in the Alpine-Himalayan belt and by the Mid-Atlantic ridge.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0040-1951(97)00031-0","issn":"00401951","usgsCitation":"Huber, K., Fuchs, K., Palmer, J., Roth, F., Khakhaev, B., Van-Kin, L.E., Pevzner, L., Hickman, S., Moos, D., Zoback, M.D., and Schmitt, D., 1997, Analysis of borehole televiewer measurements in the Vorotilov drillhole, Russia - First results: Tectonophysics, v. 275, no. 1-3, p. 261-272, https://doi.org/10.1016/S0040-1951(97)00031-0.","productDescription":"12 p.","startPage":"261","endPage":"272","costCenters":[],"links":[{"id":228132,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Russia","otherGeospatial":"Vorotilov drillhole","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n 43.85361151516585,\n 56.377878378335424\n ],\n [\n 43.85361151516585,\n 56.24665273409747\n ],\n [\n 44.20560894507008,\n 56.24665273409747\n ],\n [\n 44.20560894507008,\n 56.377878378335424\n ],\n [\n 43.85361151516585,\n 56.377878378335424\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"275","issue":"1-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059eb0ae4b0c8380cd48b92","contributors":{"authors":[{"text":"Huber, K.","contributorId":18230,"corporation":false,"usgs":true,"family":"Huber","given":"K.","email":"","affiliations":[],"preferred":false,"id":383658,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fuchs, K.","contributorId":89666,"corporation":false,"usgs":true,"family":"Fuchs","given":"K.","email":"","affiliations":[],"preferred":false,"id":383664,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Palmer, J.","contributorId":25040,"corporation":false,"usgs":true,"family":"Palmer","given":"J.","affiliations":[],"preferred":false,"id":383660,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Roth, F.","contributorId":92929,"corporation":false,"usgs":true,"family":"Roth","given":"F.","email":"","affiliations":[],"preferred":false,"id":383665,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Khakhaev, B.N.","contributorId":17101,"corporation":false,"usgs":true,"family":"Khakhaev","given":"B.N.","email":"","affiliations":[],"preferred":false,"id":383657,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Van-Kin, L. E.","contributorId":52043,"corporation":false,"usgs":true,"family":"Van-Kin","given":"L.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":383661,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Pevzner, L.A.","contributorId":6327,"corporation":false,"usgs":true,"family":"Pevzner","given":"L.A.","email":"","affiliations":[],"preferred":false,"id":383656,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Hickman, S.","contributorId":79995,"corporation":false,"usgs":true,"family":"Hickman","given":"S.","email":"","affiliations":[],"preferred":false,"id":383662,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Moos, Daniel","contributorId":105048,"corporation":false,"usgs":true,"family":"Moos","given":"Daniel","affiliations":[],"preferred":false,"id":383666,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Zoback, Mark D.","contributorId":80275,"corporation":false,"usgs":true,"family":"Zoback","given":"Mark","middleInitial":"D.","affiliations":[],"preferred":false,"id":383663,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Schmitt, D.","contributorId":19395,"corporation":false,"usgs":true,"family":"Schmitt","given":"D.","email":"","affiliations":[],"preferred":false,"id":383659,"contributorType":{"id":1,"text":"Authors"},"rank":11}]}} ,{"id":70020159,"text":"70020159 - 1997 - El Salvador, Chile porphyry copper deposit revisited: Geologic and geochronologic framework","interactions":[],"lastModifiedDate":"2024-03-15T11:22:13.083855","indexId":"70020159","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2020,"text":"International Geology Review","active":true,"publicationSubtype":{"id":10}},"title":"El Salvador, Chile porphyry copper deposit revisited: Geologic and geochronologic framework","docAbstract":"The Eocene (42 to 41 Ma) El Salvador porphyry copper deposit in the Indio Muerto district, northern Chile (26° 15′ S Lat.), formerly thought to have formed at the culmination of a 9-m.y. period of episodic magmatism, is shown by new mapping, U-Pb and K-Ar geochronology, and petrologic data to have formed during the younger of two distinct but superposed magmatic events-a Paleocene (∼63 to 58 Ma) and an Eocene (44 to 41 Ma) event. In the district, high-K Paleocene volcano-plutonic activity was characterized by a variety of eruptive styles and magmatic compositions, including a collapse caldera associated with explosive rhyolitic magmatism (El Salvador trapdoor caldera), a post-collapse rhyolite dome field (Cerro Indio Muerto), and andesitic-trachyandesitic stratovolcanos (Kilometro Catorce-Los Amarillos sequence). Pre-caldera basement faults were reactivated during Paleocene volcanism as part of the collapse margin of the caldera. Beneath Cerro Indio Muerto, where the porphyry Cu deposit subsequently formed, the intersection of two major basement faults and the NNE-striking rotational axis of tilted ignimbrites of the Paleocene El Salvador caldera localized emplacement of post-collapse rhyolite domes and peripheral dikes and sills. Subsequent Eocene rhyolitic and granodioritic-dacitic porphyries intruded ~14 m.y. after cessation of Paleocene magmatism along the same NNE-striking structural belt through Cerro Indio Muerto as did the post-collapse Paleocene rhyolite domes. Eocene plutonism over a 3-m.y. period was contemporaneous with NW-SE-directed shortening associated with regional sinistral transpression along the Sierra Castillo fault, lying ∼10 km to the east. Older Eocene rhyolitic porphyries in the Indio Muerto district were emplaced between 44 and 43 Ma, and have a small uneconomic Cu center associated with a porphyry at Old Camp. The oldest granodioritic-dacitic porphyries also were emplaced at ∼44 to 43 Ma, but their petrogenetic relation to the rhyolitic porphyries and younger granodioritic-dacitic porphyries in the district is unclear. The main porphyry Cu-Mo-related granodioritic-dacitic stocks in Quebrada Turquesa on Cerro Indio Muerto intruded, cooled, and were mineralized within ∼1 m.y. between 42 and 41 Ma. Volumetrically minor late- to post-mineral porphyries are slightly more mafic than earlier granodioritic-dacitic porphyries, a compositional trend possibly repeated on several scales and more than once over the 3-million-year Eocene magmatic history of the Indio Muerto district. This compositional trend requires either addition of basaltic material into an open-system silicic magma chamber or tapping of progressively deeper levels of a vertically zoned magma chamber. Eocene porphyry magmas were more hydrous and their residual source mineralogy richer in garnet than the relatively anhydrous Paleocene rocks, whose source was rich in pyroxene. The presence of inherited zircons in Paleocene and Eocene rocks requires interaction with crustal rocks of Paleozoic and/or Proterozoic age.
","language":"English","publisher":"Taylor and Francis","doi":"10.1080/00206819709465258","issn":"00206814","usgsCitation":"Cornejo, P., Tosdal, R., Mpodozis, C., Tomlinson, A., Rivera, O., and Fanning, C., 1997, El Salvador, Chile porphyry copper deposit revisited: Geologic and geochronologic framework: International Geology Review, v. 39, no. 1, p. 22-54, https://doi.org/10.1080/00206819709465258.","productDescription":"33 p.","startPage":"22","endPage":"54","numberOfPages":"33","costCenters":[],"links":[{"id":228314,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"39","issue":"1","noUsgsAuthors":false,"publicationDate":"2010-07-06","publicationStatus":"PW","scienceBaseUri":"505a0880e4b0c8380cd51b47","contributors":{"authors":[{"text":"Cornejo, P.","contributorId":48333,"corporation":false,"usgs":true,"family":"Cornejo","given":"P.","email":"","affiliations":[],"preferred":false,"id":385234,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Tosdal, R. M.","contributorId":54982,"corporation":false,"usgs":true,"family":"Tosdal","given":"R. M.","affiliations":[],"preferred":false,"id":385235,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mpodozis, C.","contributorId":66869,"corporation":false,"usgs":true,"family":"Mpodozis","given":"C.","email":"","affiliations":[],"preferred":false,"id":385236,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Tomlinson, A.J.","contributorId":79255,"corporation":false,"usgs":true,"family":"Tomlinson","given":"A.J.","email":"","affiliations":[],"preferred":false,"id":385238,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Rivera, O.","contributorId":78102,"corporation":false,"usgs":true,"family":"Rivera","given":"O.","email":"","affiliations":[],"preferred":false,"id":385237,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Fanning, C.M.","contributorId":82434,"corporation":false,"usgs":true,"family":"Fanning","given":"C.M.","email":"","affiliations":[],"preferred":false,"id":385239,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70020053,"text":"70020053 - 1997 - Induced polarization research at Kennecott, 1965-1977","interactions":[],"lastModifiedDate":"2012-03-12T17:19:19","indexId":"70020053","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2610,"text":"Leading Edge (Tulsa, OK)","active":true,"publicationSubtype":{"id":10}},"title":"Induced polarization research at Kennecott, 1965-1977","docAbstract":"Geophysics research and development (R&D) was a small research group at Kennecott Inc. (KEI), a subsidiary of Kennecott Copper Corporation. The research group served Geophysics-Operations, which in turn worked for another subsidiary, Bear Creek Mining Company (BCMC). BCMC did Kennecott's exploration work such as reconnaissance mapping, staking and proving up claims, and assessment drilling. The working environment at Geophysics R&D included emphasis on instrument development and being strongly field oriented; having entrepreneurial leaders engaged in technical work; interaction between R&D and its `customer', the Operations group and; emphasis on lowering costs and increasing production.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Leading Edge (Tulsa, OK)","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Soc of Exploration Geophysicists","publisherLocation":"Tulsa, OK, United States","doi":"10.1190/1.1437648","issn":"1070485X","usgsCitation":"Nelson, P.H., 1997, Induced polarization research at Kennecott, 1965-1977: Leading Edge (Tulsa, OK), v. 16, no. 1, p. 29-33, https://doi.org/10.1190/1.1437648.","startPage":"29","endPage":"33","numberOfPages":"5","costCenters":[],"links":[{"id":206022,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1190/1.1437648"},{"id":227907,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"16","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3aa9e4b0c8380cd61e78","contributors":{"authors":[{"text":"Nelson, Philip H. pnelson@usgs.gov","contributorId":862,"corporation":false,"usgs":true,"family":"Nelson","given":"Philip","email":"pnelson@usgs.gov","middleInitial":"H.","affiliations":[{"id":164,"text":"Central Energy Resources Science Center","active":true,"usgs":true}],"preferred":true,"id":384839,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70020013,"text":"70020013 - 1997 - An interactive program for computer-aided map design, display, and query: EMAPKGS2","interactions":[],"lastModifiedDate":"2013-01-21T13:17:15","indexId":"70020013","displayToPublicDate":"1997-01-01T00:00:00","publicationYear":"1997","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1315,"text":"Computers & Geosciences","printIssn":"0098-3004","active":true,"publicationSubtype":{"id":10}},"title":"An interactive program for computer-aided map design, display, and query: EMAPKGS2","docAbstract":"EMAPKGS2 is a user-friendly, PC-based electronic mapping tool for use in hydrogeologic exploration and appraisal. EMAPKGS2 allows the analyst to construct maps interactively from data stored in a relational database, perform point-oriented spatial queries such as locating all wells within a specified radius, perform geographic overlays, and export the data to other programs for further analysis. EMAPKGS2 runs under Microsoft?? Windows??? 3.1 and compatible operating systems. EMAPKGS2 is a public domain program available from the Kansas Geological Survey. EMAPKGS2 is the centerpiece of WHEAT, the Windows-based Hydrogeologic Exploration and Appraisal Toolkit, a suite of user-friendly Microsoft?? Windows??? programs for natural resource exploration and management. The principal goals in development of WHEAT have been ease of use, hardware independence, low cost, and end-user extensibility. WHEAT'S native data format is a Microsoft?? Access?? database. WHEAT stores a feature's geographic coordinates as attributes so they can be accessed easily by the user. The WHEAT programs are designed to be used in conjunction with other Microsoft?? Windows??? software to allow the natural resource scientist to perform work easily and effectively. WHEAT and EMAPKGS have been used at several of Kansas' Groundwater Management Districts and the Kansas Geological Survey on groundwater management operations, groundwater modeling projects, and geologic exploration projects. ?? 1997 Elsevier Science Ltd.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Computers and Geosciences","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/S0098-3004(96)00070-2","issn":"00983004","usgsCitation":"Pouch, G., 1997, An interactive program for computer-aided map design, display, and query: EMAPKGS2: Computers & Geosciences, v. 23, no. 3, p. 259-266, https://doi.org/10.1016/S0098-3004(96)00070-2.","startPage":"259","endPage":"266","numberOfPages":"8","costCenters":[],"links":[{"id":227904,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":266159,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0098-3004(96)00070-2"}],"volume":"23","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ea84e4b0c8380cd488f9","contributors":{"authors":[{"text":"Pouch, G.W.","contributorId":71710,"corporation":false,"usgs":true,"family":"Pouch","given":"G.W.","email":"","affiliations":[],"preferred":false,"id":384703,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":24369,"text":"ofr96557 - 1996 - Gaining, losing, and dry stream reaches at Bear Creek Valley, Oak Ridge, Tennessee, March and September 1994","interactions":[],"lastModifiedDate":"2022-12-23T22:52:46.705603","indexId":"ofr96557","displayToPublicDate":"1997-05-01T00:00:00","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":"96-557","title":"Gaining, losing, and dry stream reaches at Bear Creek Valley, Oak Ridge, Tennessee, March and September 1994","docAbstract":"A study was conducted to delineate stream reaches that were gaining flow, losing flow, or that were dry in the upper reaches of Bear Creek Valley near the Y-12 Plant in Oak Ridge, Tennessee. The study included a review of maps and discharge data from a seepage investigation conducted at Bear Creek Valley; preparation of tables showing site identification and discharge and stream reaches that were gaining flow, losing flow, or that were dry; and preparation of maps showing measurement site locations and discharge measurements, and gaining, losing, and dry stream reaches. This report will aid in developing a better understanding of ground-water and surface-water interactions in the upper reaches of Bear Creek.","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ofr96557","usgsCitation":"Robinson, J.A., and Mitchell, R.L., 1996, Gaining, losing, and dry stream reaches at Bear Creek Valley, Oak Ridge, Tennessee, March and September 1994: U.S. Geological Survey Open-File Report 96-557, Report: iii, 17 p.; 1 Plate: 27.14 x 21.91 inches, https://doi.org/10.3133/ofr96557.","productDescription":"Report: iii, 17 p.; 1 Plate: 27.14 x 21.91 inches","costCenters":[],"links":[{"id":411043,"rank":4,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_18648.htm","linkFileType":{"id":5,"text":"html"}},{"id":53467,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1996/0557/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":53466,"rank":3,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/of/1996/0557/plate-1.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":156256,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1996/0557/report-thumb.jpg"}],"country":"United States","state":"Tennessee","city":"Oak Ridge","otherGeospatial":"Bear Creek Valley","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -84.28044454354242,\n 36.00270945658738\n ],\n [\n -84.28044454354242,\n 35.96049748128307\n ],\n [\n -84.24287353421924,\n 35.96049748128307\n ],\n [\n -84.24287353421924,\n 36.00270945658738\n ],\n [\n -84.28044454354242,\n 36.00270945658738\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b28e4b07f02db6b1457","contributors":{"authors":[{"text":"Robinson, J. A.","contributorId":57417,"corporation":false,"usgs":true,"family":"Robinson","given":"J.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":191793,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mitchell, R. L.","contributorId":41458,"corporation":false,"usgs":true,"family":"Mitchell","given":"R.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":191792,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":24372,"text":"ofr95459 - 1996 - Results of a seepage investigation at Bear Creek Valley, Oak Ridge, Tennessee, January through September 1994","interactions":[],"lastModifiedDate":"2012-02-02T00:08:11","indexId":"ofr95459","displayToPublicDate":"1996-12-01T00:00:00","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":"95-459","title":"Results of a seepage investigation at Bear Creek Valley, Oak Ridge, Tennessee, January through September 1994","docAbstract":"A seepage investigation was conducted of 4,600 acres of Bear Creek Valley southwest of the Y-12 Plant, Oak Ridge, Tennessee, for the period of January through September 1994. The data were collected to help the Y-12 Environmental Restoration Program develop a better understanding of ground-water and surface-water interactions, recharge and discharge relations, and ground-water flow patterns. The project was divided into three phases: a reconnaissance and mapping of seeps, springs, and stream-measurment sites; a high base flow seepage investigation; and a low base flow seepage investigation. The reconnaissance was conducted from January 6 to March 1, 1994, to identify and map the locations of seeps, springs, and stream-measurement sites. A total of 701 sites were identified. They consisted of 382 stream- measurement sites, 265 seeps, 48 springs, and 6 wetlands. A global positioning system was used to locate 680 sites to within 3- to 5-meter accuracy. The high base flow seepage investigation was conducted from March 14 through March 19, 1994. Measurements were made at 579 of the 701 sites identified in the reconnaissance that still had flowing water. Flow rates ranged from less than 0.005 to 6.89 cubic feet per second for the streams, from less than 0.005 to 0.13 cubic foot per second for the seeps, and from less than 0.005 to 1 cubic foot per second for the springs. pH ranged from 5.0 to 8.4 for the streams, from 5.1 to 8.2 for the seeps, from 5.3 to 8.0 for the springs, and from 6.7 to 6.8 for the wetland sites. Specific conductance ranged from 16 to 1,670 microsiemens per centimeter for the streams, from 17 to 1,710 microsiemens per centimeter for the seeps, from 14 to 1,150 microsiemens per centimeter for the springs, and from 102 to 160 microsiemens per centimeter for the wetland sites. Temperature ranged from 4.5 to 16.0 degrees Celsius for the streams, from 5.0 to 21.0 degrees Celsius for the seeps, from 6.0 to 13.5 degrees Celsius for the springs, and from 13.0 to 19.5 degrees Celsius for the wetland sites. Dissolved oxygen ranged from 4.8 to 11.2 milligrams per liter for the streams, 1.2 to 11.3 milligrams per liter for the seeps, and from 0.6 to 11.0 milligrams per liter for the springs. Dissolved oxygen at a wetland site measured 3.8 milligrams per liter. The low base flow investigation was conducted from September 9 through September 29, 1994. The stream sites, seeps, and springs that had flow during the high base flow seepage investigation were revisited. One-hundred seventy-six of the stream sites visited still had flow. Discharge ranged from less than 0.005 to 0.76 cubic foot per second; pH, from 4.8 to 8.3; specific conductance, from 47 to 2,030 microsiemens per centimeter; temperature, from 13.5 to 22.5 degrees Celsius; and dissolved oxygen, from 3.6 to 8.7 milligrams per liter. Twenty-five of the seeps visited were flowing and had discharge ranging from less than 0.005 to 0.01 cubic foot per second; pH, from 6.0 to 7.7; specific conductance, from 36 to 395 microsiemens per centimeter; temperature, from 16.0 to 21.0 degrees Celsius; and dissolved oxygen, from 2.2 to 9.0 milligrams per liter. Thirty springs visited were flowing and had discharge ranging from less than 0.005 to 0.37 cubic foot per second; pH, from 6.5 to 7.7; specific conductance, from 26 to 1,220 microsiemens per centimeter; temperature, from 14.0 to 20.0 degrees Celsius; and dissolved oxygen, from 1.0 to 9.2 milligrams per liter. All of the wetland sites visited were dry.","language":"ENGLISH","publisher":"U.S. Geological Survey,","doi":"10.3133/ofr95459","issn":"0094-9140","usgsCitation":"Robinson, J.A., and Johnson, G., 1996, Results of a seepage investigation at Bear Creek Valley, Oak Ridge, Tennessee, January through September 1994: U.S. Geological Survey Open-File Report 95-459, iv, 45 p. :ill., maps ;28 cm., https://doi.org/10.3133/ofr95459.","productDescription":"iv, 45 p. :ill., maps ;28 cm.","costCenters":[],"links":[{"id":156276,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1995/0459/report-thumb.jpg"},{"id":19501,"rank":400,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/of/1995/0459/plate-1_a.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":19502,"rank":401,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/of/1995/0459/plate-1_b.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":53468,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1995/0459/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a14e4b07f02db602c25","contributors":{"authors":[{"text":"Robinson, J. A.","contributorId":57417,"corporation":false,"usgs":true,"family":"Robinson","given":"J.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":191800,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Johnson, G.C.","contributorId":14450,"corporation":false,"usgs":true,"family":"Johnson","given":"G.C.","email":"","affiliations":[],"preferred":false,"id":191799,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018568,"text":"70018568 - 1996 - Potential role of vegetation feedback in the climate sensitivity of high-latitude regions: A case study at 6000 years B.P.","interactions":[],"lastModifiedDate":"2023-11-29T16:24:05.038875","indexId":"70018568","displayToPublicDate":"1996-12-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1836,"text":"Global Biogeochemical Cycles","active":true,"publicationSubtype":{"id":10}},"title":"Potential role of vegetation feedback in the climate sensitivity of high-latitude regions: A case study at 6000 years B.P.","docAbstract":"Previous climate model simulations have shown that the configuration of the Earth's orbit during the early to mid-Holocene (approximately 10–5 kyr) can account for the generally warmer-than-present conditions experienced by the high latitudes of the northern hemisphere. New simulations for 6 kyr with two atmospheric/mixed-layer ocean models (Community Climate Model, version 1, CCMl, and Global ENvironmental and Ecological Simulation of Interactive Systems, version 2, GENESIS 2) are presented here and compared with results from two previous simulations with GENESIS 1 that were obtained with and without the albedo feedback due to climate-induced poleward expansion of the boreal forest. The climate model results are summarized in the form of potential vegetation maps obtained with the global BIOME model, which facilitates visual comparisons both among models and with pollen and plant macrofossil data recording shifts of the forest-tundra boundary. A preliminary synthesis shows that the forest limit was shifted 100–200 km north in most sectors. Both CCMl and GENESIS 2 produced a shift of this magnitude. GENESIS 1 however produced too small a shift, except when the boreal forest albedo feedback was included. The feedback in this case was estimated to have amplified forest expansion by approximately 50%. The forest limit changes also show meridional patterns (greatest expansion in central Siberia and little or none in Alaska and Labrador) which have yet to be reproduced by models. Further progress in understanding of the processes involved in the response of climate and vegetation to orbital forcing will require both the deployment of coupled atmosphere-biosphere-ocean models and the development of more comprehensive observational data sets.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/96GB02690","usgsCitation":"Kutzbach, J., Bartlein, P., Foley, J., Harrison, S.P., Hostetler, S.W., Liu, Z., Prentice, I.C., and Webb, T., 1996, Potential role of vegetation feedback in the climate sensitivity of high-latitude regions: A case study at 6000 years B.P.: Global Biogeochemical Cycles, v. 10, no. 4, p. 727-736, https://doi.org/10.1029/96GB02690.","productDescription":"10 p.","startPage":"727","endPage":"736","numberOfPages":"10","costCenters":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"links":[{"id":227612,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"10","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a7f5be4b0c8380cd7aaa3","contributors":{"authors":[{"text":"Kutzbach, J.-E.","contributorId":93221,"corporation":false,"usgs":true,"family":"Kutzbach","given":"J.-E.","email":"","affiliations":[],"preferred":false,"id":380075,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bartlein, P. J.","contributorId":54566,"corporation":false,"usgs":false,"family":"Bartlein","given":"P. J.","affiliations":[],"preferred":false,"id":380070,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Foley, J.A.","contributorId":11782,"corporation":false,"usgs":true,"family":"Foley","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":380068,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Harrison, S. P.","contributorId":78488,"corporation":false,"usgs":false,"family":"Harrison","given":"S.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":380074,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Hostetler, Steven W.. 0000-0003-2272-8302 swhosteller@usgs.gov","orcid":"https://orcid.org/0000-0003-2272-8302","contributorId":69731,"corporation":false,"usgs":true,"family":"Hostetler","given":"Steven","email":"swhosteller@usgs.gov","middleInitial":"W..","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":false,"id":380072,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Liu, Z.","contributorId":70943,"corporation":false,"usgs":true,"family":"Liu","given":"Z.","email":"","affiliations":[],"preferred":false,"id":380073,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Prentice, I. C.","contributorId":63969,"corporation":false,"usgs":true,"family":"Prentice","given":"I.","middleInitial":"C.","affiliations":[],"preferred":false,"id":380071,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Webb, T. III","contributorId":38297,"corporation":false,"usgs":true,"family":"Webb","given":"T.","suffix":"III","email":"","affiliations":[],"preferred":false,"id":380069,"contributorType":{"id":1,"text":"Authors"},"rank":8}]}} ,{"id":24711,"text":"ofr95762 - 1996 - Real-Time Mapping alert system; user's manual","interactions":[],"lastModifiedDate":"2012-02-02T00:08:24","indexId":"ofr95762","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":"95-762","title":"Real-Time Mapping alert system; user's manual","docAbstract":"The U.S. Geological Survey has an extensive hydrologic network that records and transmits precipitation, stage, discharge, and other water- related data on a real-time basis to an automated data processing system. Data values are recorded on electronic data collection platforms at field monitoring sites. These values are transmitted by means of orbiting satellites to receiving ground stations, and by way of telecommunication lines to a U.S. Geological Survey office where they are processed on a computer system. Data that exceed predefined thresholds are identified as alert values. These alert values can help keep water- resource specialists informed of current hydrologic conditions. The current alert status at monitoring sites is of critical importance during floods, hurricanes, and other extreme hydrologic events where quick analysis of the situation is needed. This manual provides instructions for using the Real-Time Mapping software, a series of computer programs developed by the U.S. Geological Survey for quick analysis of hydrologic conditions, and guides users through a basic interactive session. The software provides interactive graphics display and query of real-time information in a map-based, menu-driven environment.","language":"ENGLISH","publisher":"U.S. Geological Survey ;\r\nEarth Science Information Center, Open-File Reports Section [distributor],","doi":"10.3133/ofr95762","issn":"0094-9140","usgsCitation":"Torres, L., 1996, Real-Time Mapping alert system; user's manual: U.S. Geological Survey Open-File Report 95-762, vi, 49 p. :ill., maps ;28 cm., https://doi.org/10.3133/ofr95762.","productDescription":"vi, 49 p. :ill., maps ;28 cm.","costCenters":[],"links":[{"id":157519,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1995/0762/report-thumb.jpg"},{"id":53743,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1995/0762/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a53e4b07f02db62b5ed","contributors":{"authors":[{"text":"Torres, L.A.","contributorId":19195,"corporation":false,"usgs":true,"family":"Torres","given":"L.A.","email":"","affiliations":[],"preferred":false,"id":192416,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ]}