Eight characteristics of sediments are considered as possible means of recognizing source beds: 1, quantity of organic matter in the sediments; 2, reducing power, which is a measure of ability of the sediments to reduce chromic acid; 3, color of sediments; 4, volatility of sediments; 5, degree of volatility, which is a measure of the volatility with respect to the organic content; 6, ratio of carbon to nitrogen in the sediments; 7, oxidation factor, which is an index of the state of oxidation of the sediments, and is the ratio of the carbon content to' the reducing power; and, 8, the nitrogen-reduction ratio, which is the ratio of the nitrogen content to the reducing power. Several thousand determinations of these characteristics have been made and averaged from more than 800 lithologic units from many areas in the California, Rocky Mountain, Mid Continent, East Texas, and Gulf Coast oil regions. The thickness of these units ranges from 50 ft. to 500 ft. Each of them has been classified according to its probable richness in source material of petroleum. Nearness to producing zones has been the basis of classification, as it seems more reasonable to assume that oil in general accumulates near where it is generated than to assume that it ordinarily accumulates far from where it is made. Three classes were made: 1, lithologic units within 250 ft. stratigraphically above or below an oil zone and less than 2 miles from an oil field; 2, (a) units within 500 ft. above or below an oil zone and within 15 miles of an oil field (excluding, of course, those that belong to the first class) and (b) units within 250 ft. stratigraphically of a horizon and more than 15 miles distant from an oil field, provided the unit is located within a region in which the horizon is generally productive of oil or yields significant quantity of oily substances when extracted with ether; and, 3, all other beds, viz., those more than 500 ft. above or below an oil horizon or more than 15 miles distant from an oil field and beds at greater distance if they are within 250 ft. of horizons that generally contain oil in the area. These three classes are designated in this report as \" productive,\" \" questionably productive,\" and \" barren.\" \" Productive \" units naturally may contain spine beds that are poor in source material, and \" barren \" units may contain beds that are rich in source material; but, on the whole, the \" productive \" units-because of their nearness to oil zones-are more likely' to be richer in mother substances of petroleum than are the \" barren \" units. Each of the eight characteristics was averaged for each of the three classes of productivity, for each of the five oil areas: California, Rocky Mountains, Mid Continent, East Texas, and Gulf Coast. The average organic content of the \"productive\" and \" barren \" units was found to be approximately the same in each region studied, from which it is inferred that the quantity of organic matter in a sediment probably is not a reliable guide of the ability of the sediments to generate oil. The average reducing power of the \" productive \" beds is slightly greater than that of the \"barren\"; but the difference is so slight that the reducing power, also, probably is not a satisfactory guide to source beds. The color of, the sediments, in general, becomes darker as the organic content of the sediments increases; and, as the organic content seems to be a poor index of source beds, color presumably is not a serviceable means of recognizing source beds. The volatility of the \" productive \" beds is greater than that of the \" barren \" units in each of the five regions, but it differs so much from region to region that it cannot be used as an index of source beds unless the general volatility of the sediments in the region under consideration is known. For example, the average volatility of the \" barren \" units in California and the Rocky Mountain regions is greater than that of the \" productive \" units in the Mid Continent, East Texas, and Gulf Coast areas. The degree of volatility differs less from region to region than does the volatility, and in general exhibits a relationship to productivity equally as good as the volatility. The average ratio of carbon to nitrogen in each of the three regions from which data are available-Rocky Mountains, Mid Continent, and East Texas-is higher for \" productive \" beds than for \" barren \" units, but the ratio differs somewhat from one region to another. The oxidation factor of the \" productive \" units is approximately the same as that of the \" barren \" units in the Rocky Mountain region and in the East Texas region, but not in the Mid Continent region-where the oxidation factor of the \" productive \" units is definitely lower than that of the \" barren \" units. The average nitrogen-reduction ratio of the \" productive \" units is decidedly greater than that of the \" barren \" units in each of the five regions studied; and it, therefore, is the most reliable of the guides studied. Relatively few \" productive \" units have nitrogen-reduction ratios greater than 7.0, and relatively few \" barren \" units have ratios of less than 4.5. A considerable number of both \" productive \" and \" barren \" units have ratios ranging between 4.5 and 7.0, but even between these limits the productive units tend to be more commonly associated with low ratios than are the \" barren \" units. Four of these eight characteristics-volatility, degree of volatility, carbon-nitrogen ratio, and nitrogen-reduction ratio-therefore, give promise of being useful means of recognizing source beds; and one of them, the nitrogen-reduction ratio, is particularly encouraging. Additional studies of these four characteristics, and especially of the nitrogen-reduction ratio, are highly desirable.
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","language":"English","publisher":"U.S. Government Printing Office","publisherLocation":"Washington, D.C.","doi":"10.3133/b853","usgsCitation":"McKnight, E., 1935, Zinc and lead deposits of northern Arkansas: U.S. Geological Survey Bulletin 853, Report: iv, 311 p.; 6 Plates: 27.46 x 19.97 inches or smaller, https://doi.org/10.3133/b853.","productDescription":"Report: iv, 311 p.; 6 Plates: 27.46 x 19.97 inches or smaller","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":93161,"rank":400,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/0853/plate-03.pdf","text":"Plate 3","linkFileType":{"id":1,"text":"pdf"}},{"id":93162,"rank":401,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/0853/plate-03_a.pdf","text":"Plate 3A","linkFileType":{"id":1,"text":"pdf"}},{"id":93163,"rank":402,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/0853/plate-04.pdf","text":"Plate 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Edwin T.","contributorId":85039,"corporation":false,"usgs":true,"family":"McKnight","given":"Edwin T.","affiliations":[],"preferred":false,"id":214199,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":478,"text":"wsp742 - 1935 - Surface water supply of the United States, 1933, Part II, South Atlantic slope and eastern Gulf of Mexico basins","interactions":[],"lastModifiedDate":"2012-02-02T00:05:12","indexId":"wsp742","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1935","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":341,"text":"Water Supply Paper","code":"WSP","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"742","title":"Surface water supply of the United States, 1933, Part II, South Atlantic slope and eastern Gulf of Mexico basins","language":"ENGLISH","publisher":"U.S. Govt. Print. Off.,","doi":"10.3133/wsp742","usgsCitation":"Water Resources Division, U.S. Geological Survey, 1935, Surface water supply of the United States, 1933, Part II, South Atlantic slope and eastern Gulf of Mexico basins: U.S. Geological Survey Water Supply Paper 742, vii, 206 p. ;23 cm., https://doi.org/10.3133/wsp742.","productDescription":"vii, 206 p. ;23 cm.","costCenters":[],"links":[{"id":137420,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wsp/0742/report-thumb.jpg"},{"id":25041,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wsp/0742/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4afee4b07f02db697822","contributors":{"authors":[{"text":"Water Resources Division, U.S. Geological Survey","contributorId":128075,"corporation":true,"usgs":false,"organization":"Water Resources Division, U.S. Geological Survey","id":527450,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70160862,"text":"70160862 - 1935 - Geology and ground-water resources of the island of Oahu, Hawaii","interactions":[],"lastModifiedDate":"2016-01-06T08:55:05","indexId":"70160862","displayToPublicDate":"1939-01-01T10:00:00","publicationYear":"1935","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":4,"text":"Other Government Series"},"seriesTitle":{"id":242,"text":"Bulletin","active":false,"publicationSubtype":{"id":4}},"seriesNumber":"1","title":"Geology and ground-water resources of the island of Oahu, Hawaii","docAbstract":"Oahu, one of the islands of the Hawaiian group, lies in the Mid-Pacific 2,100 miles southwest of San Francisco. The principal city is Honolulu. The Koolau Range makes up the eastern part of the island, and the Waianae Range the western part. Both are extinct basaltic volcanoes deeply dissected by erosion. The Koolau Volcano was the later to become extinct.
The Waianae Range is made up of three groups of lavas erupted in Tertiary and possibly in early Pleistocene time. The exposed part of the older lava is nearly 2,000 feet thick and consists largely of thin-bedded pahoehoe. It is separated in most places from the middle lavas by an angular unconformity and talus breccia and in a few places by an erosional unconformity. The middle basalts are about 2,000 feet thick and closely resemble the lower ones except that they contain more aa. The upper lavas reach a thickness of about 2,300 feet and are mostly massive aa flows. The last eruptions produced large cinder cones and some nephelite basalts. The Waianae Volcano, like other Hawaiian volcanoes, produced only small amounts of ash, and the lavas were largely extruded from fissures a few feet wide, now occupied by dikes. The center of activity was near Kolekole Pass, at the head of Lualualei Valley.
The Koolau Volcano is made up of two groups of lavas extruded in Tertiary and early Pleistocene (?) time. The older group, the Kailua volcanic series, is greatly altered by hydrothermal action and was extruded from fissures near Lanikai. The flows of the younger group, the Koolau volcanic series, were extruded from fissures about a mile south of the Kailua rift and have an exposed thickness of about 3,000 feet. The Koolau Volcano produced even less ash than the Waianae Volcano, and its flows are thin-bedded pahoehoe and aa. The eruptive center of the Koolau Volcano lies between Kaneohe and Waimanalo.
Great amounts of both the Waianae and Koolau Ranges were removed by fluvial and marine erosion during the Pleistocene. The master streams are characterized by deep amphitheater-headed valleys. After this erosion cycle the island was submerged more than 1,200 feet, and these great valleys were drowned and alluviated. Besides this submergence, several strand lines, preserved up to 100 feet above present sea level occur, which may be due to world-wide changes in sea level in response to the withdrawal and restoration of water concurrent with the advances and recessions of the polar ice caps and to accompanying changes in the ocean floor. During this time of shifting ocean levels spasmodic eruptions occurred on the southeast end of the Koolau Range, producing numerous lava flows and tuff cones, most of which are nephelite basalt.
The last of these eruptions occurred in Recent time. A description of the climate, rates of run-off, and results of experiments to determine evaporation and transpiration in the areas of high rainfall are given. It was found that the consumptive use decreases materially and becomes a very small percentage of the rainfall in the areas of high precipitation.
The lava rocks of the island are very permeable and, because of a rainfall reaching a maximum of 300 inches a year, carry large amounts of ground water, confined and unconfined, basal and perched. The basal ground water floats on salt water because of its lower specific gravity. Consequently for each foot the water table stands above sea level, salt water lies about 42 feet below sea level, in accordance with the sea along the coast as basal ground water. In most places the lava rocks along the shore are overlain by an impermeable or nearly impermeable caprock consisting of submerged lateritic soils and marine noncalcareous sediments. These deposits retard the escape of basal ground water into the sea and give rise to artesian water, but unlike most other artesian systems, this one has no lower restraining formation.
The artesian water is the principal source of domestic, municipal, and irrigation supplies. The average annual quantity pumped for the period 1928 to 1933 amounted to about 105,000,000,000 gallons, nearly 90 percent of which came from Koolau hasalt and the remainder from Waianae basalt.
There are ten artesian areas in the Koolau Range and two in the Waianae Range. Hydraulic gradients in these basins were found to range from 1.2 to 3 feet to the mile. Because of these extremely flat gradients and the high permeability of the aquifers it is possible to reverse the hydraulic gradients by draft and make the water flow from one artesian area to another.
The artesian water levels fluctuate in response to seasonal variations in draft and recharge and in a lesser way to tidal, barometric, and seismic pressures.
The water, as shown by chemical analysis, is of excellent quality except where it is contaminated with sea water. Methods have been devised for freshening wells that have gone salty, for detecting leaks, for sealing leaky and defective wells, and for recharging the artesian basins.
Owing to the danger of the wells becoming brackish with increased draft, it is believed that further large developments will be more successful if shafts are sunk to sea level in the basalt as far inland as practicable, and tunnels are driven from the bottom of the shafts near the top of the saturated zone. Favorable places for such development exist in Honolulu.
In addition to the basal water in the volcanic rocks, water is found in the recent gravel, beach, and dune deposits, and the emerged reef limestone. This water has been recovered by wells and tunnels, and there are favorable localities for developing additional water of this type.
The island contains two types of basal springs—those like the Pearl Harbor Springs, which issue from basalt and are supplied by overflow and leakage from the artesian basin, and those which issue from the coastal-plain sediments and are mainly return irrigation water. The total quantity of basal ground water issuing as springs is estimated to be 100,000,000 gallons a day.
Ground water occurs at high levels, confined by dikes and perched on tuff, alluvium, and soil beds. These structures give rise to innumerable high-level springs. In the Koolau Range 60 tunnels yield about 33,000,000 gallons daily, of which about 95 percent is obtained from tunnels penetrating the dike complex of the Koolau volcanic series, about 2 percent from tunnels entering post-Koolau ash or tuff deposits, and the remainder from tunnels whose geologic relations are not certainly known. The average daily yield of the tunnels that recover dike water is 2,330 gallons a foot, but the average daily yield of the tunnels in post-Koolau tuff is 450 gallons a foot, and that of the tunnels in alluvium or soil is only 23 gallons a foot.
Owing largely to the much lower rainfall on the Waianac Range, its 35 tunnels (not including two new tunnels under construction) yield only about 2,400,000 gallons daily, about 94 percent of which is believed to be obtained from dike systems. The average daily yield of the tunnels in this range that are supplied by dike systems is 581 gallons a foot, as compared to 5 gallons a foot from tunnels in ash or tuff.
An extensive tunnel system is proposed to develop a large supply of high-level water for Honolulu from the dike complex of the Koolau series, and high-level water can be recovered by tunnels at many other places.
The average daily discharge of all high-level springs in the Koolau Range is about 58,000,000 gallons, of which about 94 percent comes from the Koolau dike complex and about 6 percent from post-Koolau volcanic rocks. The average daily discharge of all high-level springs in the Waianae Range is about 500,000 gallons of which about 81 percent issues from the dike complex.
Rocks of rhyolitic type in eastern Idaho and adjacent parts of Wyoming were observed by the Teton Division of the Hayden Surveys under Orestes St. John (Report of the geological field work of the Teton Division, U.S. Geol. and Geog. Surv. Terr., 11th Ann. Rep., pp. 498–504, 1879), who described them as trachytes. He noted their relations to different types of underlying sedimentary rocks and their tendency to conform with the preexisting topography, but considered them all as flows. ©1935. American Geophysical Union. All Rights Reserved.
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\"}}]}","volume":"16","issue":"1","noUsgsAuthors":false,"publicationDate":"2014-08-18","publicationStatus":"PW","contributors":{"authors":[{"text":"Mansfield, G. R.","contributorId":81064,"corporation":false,"usgs":true,"family":"Mansfield","given":"G.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":775355,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ross, C.S.","contributorId":220633,"corporation":false,"usgs":false,"family":"Ross","given":"C.S.","email":"","affiliations":[],"preferred":false,"id":775356,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70241315,"text":"70241315 - 1935 - The pre-Cambrian igneous rocks of eastern Pennsylvania and Maryland","interactions":[],"lastModifiedDate":"2023-03-16T16:17:17.511783","indexId":"70241315","displayToPublicDate":"1935-08-01T11:12:16","publicationYear":"1935","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":13522,"text":"Transactions, American Geophysical Union","active":false,"publicationSubtype":{"id":10}},"title":"The pre-Cambrian igneous rocks of eastern Pennsylvania and Maryland","docAbstract":"The Blue Ridge and Piedmont geomorphic provinces, topographically distinct but geologically a unit, extend southwestward across eastern Pennsylvania and central Maryland, in a belt with an average width in these States of some 50 miles. In these provinces are exposed the crystalline formations of the Atlantic belt. Gneisses (with sporadic interbedded graphitic schist and marble), quartz-schist, crystalline limestone, and scnlsts, constitute the pre-Cambrian sedimentary series which has been folded, overturned, and overthrust with faulting, to the northwest.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/TR016i001p00328","usgsCitation":"Bascom, F., 1935, The pre-Cambrian igneous rocks of eastern Pennsylvania and Maryland: Transactions, American Geophysical Union, v. 16, no. 1, p. 328-350, https://doi.org/10.1029/TR016i001p00328.","productDescription":"23 p.","startPage":"328","endPage":"350","costCenters":[],"links":[{"id":414288,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Maryland, Pennsylvania","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -77.13061563955371,\n 39.171238776502236\n ],\n [\n -75.06024892714818,\n 41.213543500003\n ],\n [\n -76.16912330192815,\n 41.56106197840771\n ],\n [\n -77.89559859430706,\n 39.59434987834371\n ],\n [\n -77.13061563955371,\n 39.16579763068066\n ],\n [\n -77.13061563955371,\n 39.171238776502236\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"16","issue":"1","noUsgsAuthors":false,"publicationDate":"2014-08-18","publicationStatus":"PW","contributors":{"authors":[{"text":"Bascom, Florence","contributorId":107668,"corporation":false,"usgs":true,"family":"Bascom","given":"Florence","email":"","affiliations":[],"preferred":false,"id":866674,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70221657,"text":"70221657 - 1935 - Shore benches on the island of Oahu, Hawaii","interactions":[],"lastModifiedDate":"2021-06-27T15:15:08.035899","indexId":"70221657","displayToPublicDate":"1935-08-01T10:10:25","publicationYear":"1935","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1786,"text":"Geological Society of America Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Shore benches on the island of Oahu, Hawaii","docAbstract":"The Island of Oahu is third in size in the Hawaiian group and lies in the mid-Pacific about 2,100 miles southwest of San Francisco. Honolulu, the capital and principal port of this group, is on Oahu. Two dissected volcanic domes, the Waianae Range (4,035 feet high) and the Koolau Range (3,105 feet high) make up the island. They are surrounded by a nearly continuous coastal plain, in places reaching nearly 6 miles in width and consisting of emerged Pleistocene reef limestone and terrigenous deposits. A living coral reef fringes all of the island except the east and west ends.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/GSAB-46-1467","usgsCitation":"Stearns, H.T., 1935, Shore benches on the island of Oahu, Hawaii: Geological Society of America Bulletin, v. 46, no. 10, p. 1467-1482, https://doi.org/10.1130/GSAB-46-1467.","productDescription":"16 p.","startPage":"1467","endPage":"1482","costCenters":[],"links":[{"id":386780,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Hawaii","otherGeospatial":"Oahu","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -158.3184814453125,\n 21.18185076626611\n ],\n [\n -157.576904296875,\n 21.18185076626611\n ],\n [\n -157.576904296875,\n 21.825807350355362\n ],\n [\n -158.3184814453125,\n 21.825807350355362\n ],\n [\n -158.3184814453125,\n 21.18185076626611\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"46","issue":"10","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Stearns, Harold T.","contributorId":65831,"corporation":false,"usgs":true,"family":"Stearns","given":"Harold","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":818360,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70221650,"text":"70221650 - 1935 - Report of the Committee on Glaciers, 1934–35","interactions":[],"lastModifiedDate":"2021-06-26T11:48:11.931444","indexId":"70221650","displayToPublicDate":"1935-08-01T06:44:11","publicationYear":"1935","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1578,"text":"Eos, Transactions, American Geophysical Union","onlineIssn":"2324-9250","printIssn":"0096-394","active":true,"publicationSubtype":{"id":10}},"title":"Report of the Committee on Glaciers, 1934–35","docAbstract":"The members of the Committee on Glaciers for 1935 are as given in the report of the Committee for 1933–34 in the Transactions of the Fifteenth Annual Meeting with the addition of Kenneth N. Phillips (The Mazamas, Pacific Building, Portland, Oregon).
The year 1934 witnessed a further expansion of the program of systematic annual observations on the variations of American glaciers which was inaugurated by the Committee in 1931. Several of the collaborators in the field-work of their own initiative enlarged the scope of their activities, and a new group joined the movement in the Pacific Northwest, These are the Mountaineers, of Seattle, Washington, who began observations on the glaciers of Mount Baker, which are the largest in the continental United States next to those on Mount Rainier. Under the leadership of H. V. Strandberg a base-line was laid out by the Mountaineers for measurement of the recession of the Easton Glacier, on the south side of the peak.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/TR016i002p00387","usgsCitation":"Matthes, F.E., 1935, Report of the Committee on Glaciers, 1934–35: Eos, Transactions, American Geophysical Union, v. 16, no. 2, p. 387-392, https://doi.org/10.1029/TR016i002p00387.","productDescription":"6 p.","startPage":"387","endPage":"392","costCenters":[],"links":[{"id":386773,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Washington","otherGeospatial":"northwest Washington","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -123.31054687499999,\n 49.023461463214126\n ],\n [\n -123.42041015624999,\n 48.21003212234042\n ],\n [\n -124.67285156250001,\n 48.45835188280866\n ],\n [\n -125.0244140625,\n 47.97521412341618\n ],\n [\n -124.0576171875,\n 46.604167162931844\n ],\n [\n -121.86035156249999,\n 46.84516443029276\n ],\n [\n -121.53076171875,\n 48.151428143221224\n ],\n [\n -121.6845703125,\n 49.023461463214126\n ],\n [\n -123.31054687499999,\n 49.023461463214126\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"16","issue":"2","noUsgsAuthors":false,"publicationDate":"2014-08-18","publicationStatus":"PW","contributors":{"authors":[{"text":"Matthes, Francois E.","contributorId":97963,"corporation":false,"usgs":true,"family":"Matthes","given":"Francois","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":818353,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":471,"text":"wsp727 - 1934 - Surface water supply of the United States, 1932, Part II, South Atlantic slope and eastern Gulf of Mexico basins","interactions":[],"lastModifiedDate":"2012-02-02T00:05:12","indexId":"wsp727","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1934","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":341,"text":"Water Supply Paper","code":"WSP","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"727","title":"Surface water supply of the United States, 1932, Part II, South Atlantic slope and eastern Gulf of Mexico basins","language":"ENGLISH","publisher":"U.S. Govt. Print. Off.,","doi":"10.3133/wsp727","usgsCitation":"Water Resources Division, U.S. Geological Survey, 1934, Surface water supply of the United States, 1932, Part II, South Atlantic slope and eastern Gulf of Mexico basins: U.S. Geological Survey Water Supply Paper 727, vii, 221 p. ;23 cm., https://doi.org/10.3133/wsp727.","productDescription":"vii, 221 p. ;23 cm.","costCenters":[],"links":[{"id":137404,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wsp/0727/report-thumb.jpg"},{"id":25034,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wsp/0727/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4afee4b07f02db69786d","contributors":{"authors":[{"text":"Water Resources Division, U.S. Geological Survey","contributorId":128075,"corporation":true,"usgs":false,"organization":"Water Resources Division, U.S. Geological Survey","id":527443,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":3641,"text":"cir5 - 1934 - Geology of the North and South McCallum anticlines, Jackson County, Colorado, with special reference to petroleum and carbon dioxide","interactions":[],"lastModifiedDate":"2017-09-29T08:31:43","indexId":"cir5","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1934","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":"5","title":"Geology of the North and South McCallum anticlines, Jackson County, Colorado, with special reference to petroleum and carbon dioxide","docAbstract":"The McCallum anticlines, embracing an area about 2 miles wide and 12 miles long, are about 6 miles east of the town of Walden, Jackson County, Colo., on the east side of the Continental Divide. A cover of flat-lying Quaternary gravel obscures the outcrop of Pierre shale at many points on the two anticlines. Wells start in the upper part of the Pierre and penetrate all of the underlying Upper Cretaceous series to the top of the Dakota sandstone, where production of oil and carbon dioxide is obtained. The first prospecting for oil was reported in 1912, but it was not until December 1926 that oil was discovered in commercial quantities.
Two geologic sections across the anticlines, extending to the outcrop of the Dakota sandstone at the base of the Medicine Bow Range, to, the east, disclosed a marked thickening between this formation and a fossiliferous sandstone in the Pierre shale which was used as a key bed. Immediately beneath the Dakota sandstone along ore of these cross sections a sandy volcanic ash resembling that found at the horizon of the Mowry shale in Wyoming was discovered. However, it is considered here the top bed of the Morrison formation.
The impossibility of obtaining dips along the crests, owing to the cover of terrace gravel, made it necessary to construct ten structure sections across these anticlines, using the geometry of conic sections in their development. From the geometric figures developed structure contours were obtained graphically.
The occurrence of carbon dioxide in large volumes in association with petroleum on each of these anticlines provides an unusual problem in oil production. Experimental data relative to the physical properties of this gas offer an approach to the solution of the problem. The applicability of such data to actual operating conditions is yet to be tried, but the work of early investigators in the field of physical chemistry suggests the feasibility of mixing air with the carbon dioxide to assure continuity of production, which heretofore has not been attained in this area.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/cir5","usgsCitation":"Miller, J.C., 1934, Geology of the North and South McCallum anticlines, Jackson County, Colorado, with special reference to petroleum and carbon dioxide: U.S. Geological Survey Circular 5, 27 p., https://doi.org/10.3133/cir5.","productDescription":"27 p.","costCenters":[],"links":[{"id":346216,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/circ/0005/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":138384,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/circ/0005/report-thumb.jpg","linkFileType":{"id":1,"text":"pdf"}}],"country":"United States","state":"Colorado","county":"Jackson County","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -106.63330078125,\n 40.42290582797254\n ],\n [\n -106.32156372070312,\n 40.42290582797254\n ],\n [\n -106.32156372070312,\n 41.00373905329032\n ],\n [\n -106.63330078125,\n 41.00373905329032\n ],\n [\n -106.63330078125,\n 40.42290582797254\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4acce4b07f02db67e908","contributors":{"authors":[{"text":"Miller, John Charles","contributorId":97884,"corporation":false,"usgs":true,"family":"Miller","given":"John","email":"","middleInitial":"Charles","affiliations":[],"preferred":false,"id":147316,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":45335,"text":"b860A - 1934 - Part 1. The coal field from Gallup eastward toward Mount Taylor, with a measured section of pre-Dakota(?) rocks near Navajo Church","interactions":[{"subject":{"id":45335,"text":"b860A - 1934 - Part 1. The coal field from Gallup eastward toward Mount Taylor, with a measured section of pre-Dakota(?) rocks near Navajo Church","indexId":"b860A","publicationYear":"1934","noYear":false,"chapter":"A","title":"Part 1. The coal field from Gallup eastward toward Mount Taylor, with a measured section of pre-Dakota(?) rocks near Navajo Church"},"predicate":"IS_PART_OF","object":{"id":35766,"text":"b860 - 1936 - Geology and fuel resources of the southern part of the San Juan Basin, New Mexico","indexId":"b860","publicationYear":"1936","noYear":false,"title":"Geology and fuel resources of the southern part of the San Juan Basin, New Mexico"},"id":1}],"isPartOf":{"id":35766,"text":"b860 - 1936 - Geology and fuel resources of the southern part of the San Juan Basin, New Mexico","indexId":"b860","publicationYear":"1936","noYear":false,"title":"Geology and fuel resources of the southern part of the San Juan Basin, New Mexico"},"lastModifiedDate":"2026-01-21T20:11:25.971215","indexId":"b860A","displayToPublicDate":"1934-01-01T00:00:00","publicationYear":"1934","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":306,"text":"Bulletin","code":"B","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"860","chapter":"A","title":"Part 1. The coal field from Gallup eastward toward Mount Taylor, with a measured section of pre-Dakota(?) rocks near Navajo Church","docAbstract":"The report describes the geology and coal deposits of the southwestern part of the San Juan Basin, N.Mex. The field lies northeast of the town of Gallup, on the Atchison, Topeka & Santa Fe Railway, and is an irregular tract of about 630 square miles in central and west-central McKinley County; it includes the southeast corner of the Navajo Indian Reservation. Settlement is confined to the white families at a few trading posts and the Indian agency at Crown Point and to scattered Navajo Indians. The land forms, drainage, vegetation, and climate are those typical of the highland in the semiarid Southwest.
The investigation disclosed complicated relations of the Mancos shale and the Mesaverde formation, of Upper Cretaceous age, and a marked variation in the stratigraphic boundary between them. At the western edge of the field, as in the adjoining Gallup coal district, the Mancos consists of about 725 feet of marine shale almost wholly of Benton (lower Colorado) age. It is overlain by about 1,800 feet of chiefly estuarine and fluviatile deposits that represent the lower part of the Mesaverde formation. In ascending order the Mesaverde here consists of the Gallup sandstone member (which includes local lenses of valuable coal), the Dilco coal member, the Bartlett barren member, the Gibson coal member, and the Allison barren member. Eastward through the field the outcrops extend obliquely across the trend of old shore lines out into the ancient basin of marine deposition, and some of the beds consequently show a progressive lateral change into rocks of littoral and marine types. The Gallup sandstone member is in part replaced by marine shale of the Mancos. The upper part of the Dilco coal member is replaced by the Dalton sandstone member, and still farther east the bottom of the Dalton and the top of the remaining Dilco are replaced by the Mulatto tongue of the Mancos shale. The Bartlett barren member becomes coal-bearing and thus merges with the Gibson. The Gibson coal member is split by the thick Hosta sandstone member, which toward the east and northeast is in turn split by the Satan tongue of the Mancos shale, of upper Niobrara (upper Colorado) age.
In general the structure of the rocks is simple, showing a gentle northward dip into the San Juan Basin. At the west edge of the field the rocks dip steeply west in the north end of the prominent ridges known locally as the Hogback. In the eastern part there is a series of pronounced folds, whose crests and troughs retain the gentle basinward dip but whose limbs are steep monoclines that in places are faulted.
The coal is of subbituminous rank and of fairly good grade. The coal beds are very irregular and lenticular. Those in the Gallup and Dilco members are of comparatively little importance, reaching a thickness of 4 to 5 feet in only a few places and, in general, being less than 3 feet thick. The coal beds of the Gibson, especially of its lower part, are more numerous and thicker, measurements of 4 to 6 feet thick being fairly common and one bed showing a thickness of 12 feet for more than a mile. No commercial mining has been undertaken in this field, but a few small mines have been used to supply trading posts and the Indian schools at Crown Point and Tohatchi.
","largerWorkType":{"id":18,"text":"Report"},"largerWorkTitle":"Geology and fuel resources of the southern part of the San Juan Basin, New Mexico (Bulletin 860)","largerWorkSubtype":{"id":5,"text":"USGS Numbered Series"},"language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/b860A","usgsCitation":"Sears, J., 1934, Part 1. The coal field from Gallup eastward toward Mount Taylor, with a measured section of pre-Dakota(?) rocks near Navajo Church: U.S. Geological Survey Bulletin 860, Report: iv, 29 p.; 8 plates: 45.89 x 27.86 inches or smaller, https://doi.org/10.3133/b860A.","productDescription":"Report: iv, 29 p.; 8 plates: 45.89 x 27.86 inches or smaller","costCenters":[],"links":[{"id":94020,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/bul/0860a/report.pdf","text":"Report","linkFileType":{"id":1,"text":"pdf"},"description":"Report"},{"id":94005,"rank":3,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/0860a/plate-01.pdf","text":"Plate 1","linkFileType":{"id":1,"text":"pdf"},"description":"Plate 1"},{"id":94006,"rank":4,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/0860a/plate-11.pdf","text":"Plate 11","linkFileType":{"id":1,"text":"pdf"},"description":"Plate 11"},{"id":94007,"rank":5,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/0860a/plate-12.pdf","text":"Plate 12","linkFileType":{"id":1,"text":"pdf"},"description":"Plate 12"},{"id":340388,"rank":6,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/0860a/plate-13.pdf","text":"Plate 13","linkFileType":{"id":1,"text":"pdf"}},{"id":340389,"rank":7,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/0860a/plate-14.pdf","text":"Plate 14","linkFileType":{"id":1,"text":"pdf"}},{"id":340390,"rank":8,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/0860a/plate-15.pdf","text":"Plate 15","linkFileType":{"id":1,"text":"pdf"}},{"id":94008,"rank":9,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/0860a/plate-16.pdf","text":"Plate 16","linkFileType":{"id":1,"text":"pdf"},"description":"Plate 16"},{"id":94009,"rank":10,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/0860a/plate-17.pdf","text":"Plate 17","linkFileType":{"id":1,"text":"pdf"},"description":"Plate 17"},{"id":416455,"rank":11,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_93205.htm","linkFileType":{"id":5,"text":"html"}},{"id":169587,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/bul/0860a/report-thumb.jpg"}],"country":"United States","state":"New Mexico","otherGeospatial":"San Juan Basin","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -108.74267578125,\n 35.561277754384555\n ],\n [\n -107.9,\n 35.561277754384555\n ],\n [\n -107.9,\n 35.775485962767995\n ],\n [\n -108.74267578125,\n 35.775485962767995\n ],\n [\n -108.74267578125,\n 35.561277754384555\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4adce4b07f02db686222","contributors":{"authors":[{"text":"Sears, Julian D.","contributorId":42583,"corporation":false,"usgs":true,"family":"Sears","given":"Julian D.","affiliations":[],"preferred":false,"id":231436,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":45320,"text":"b846A - 1933 - Some mining districts of eastern Oregon","interactions":[{"subject":{"id":45320,"text":"b846A - 1933 - Some mining districts of eastern Oregon","indexId":"b846A","publicationYear":"1933","noYear":false,"chapter":"A","title":"Some mining districts of eastern Oregon"},"predicate":"IS_PART_OF","object":{"id":34988,"text":"b846 - 1934 - Contributions to economic geology (short papers and preliminary reports), 1933","indexId":"b846","publicationYear":"1934","noYear":false,"title":"Contributions to economic geology (short papers and preliminary reports), 1933"},"id":1}],"isPartOf":{"id":34988,"text":"b846 - 1934 - Contributions to economic geology (short papers and preliminary reports), 1933","indexId":"b846","publicationYear":"1934","noYear":false,"title":"Contributions to economic geology (short papers and preliminary reports), 1933"},"lastModifiedDate":"2022-04-27T21:20:34.123389","indexId":"b846A","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1933","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":306,"text":"Bulletin","code":"B","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"846","chapter":"A","title":"Some mining districts of eastern Oregon","docAbstract":"This report presents the results of a reconnaissance of most of the mining districts of Oregon east of the Cascade Range, with the exception of the districts in the Sumpter quadrangle. The districts described are distributed through an area roughly coincident with the Blue Mountains, which extend over much of the northeast quarter of the State.
The geology of the Blue Mountains, except for certain small areas, is known only in its most general outlines. The most widespread rocks are the Tertiary volcanic rocks, which extend over a very large part of the State. They are separated by a profound angular and erosional unconformity from the pre-Tertiary rocks.
The pre-Tertiary rocks include representatives of all the geologic periods from Carboniferous to Cretaceous, and earlier periods may also be represented.
The known Carboniferous rocks include argillite, chert, greenstone, and subordinate limestone of uncertain age and a thick series of Permian greenstone, tuff, and limestone. The Triassic rocks include shale, slate, and limestone; the Jurassic rocks are shale and slate; and the Cretaceous are conglomerate and sandstone. Schist and phyllite with some limestone and greenstone of uncertain age occur along the Burnt River west of Durkee and in the Mormon Basin.
Intrusive rocks of at least two magmatic cycles are widespread in the Blue Mountains, and the stratigraphy suggests that several cycles may be represented. The older intrusive rocks include gabbro, pyroxenite, norite, dunite, hornblende-quartz diorite, and albite granite and are characterized by a considerable degree of shearing and both cataclastic and metasomatic metamorphism. The age of some of these rocks in the Canyon Range has been fixed as Lower or Middle Triassic, and others are known to be post-Triassic. Younger biotite-quartz diorite and granodiorite of post-Triassic (possibly post-Jurassic) age are widespread, arid the ore deposits of pre-Tertiary age are believed to be genetically related to these rocks.
Representatives of the Tertiary period include Eocene volcanic rocks and sediments, Oligocene fluviatile deposits, Miocene basic lavas and fluviatile and lacustrine sediments, and Pliocene tuff and gravel. The Quaternary deposits include glacial moraines in the higher mountains, stream gravel, and volcanic ash.
The structure of the pre-Tertiary rocks is complex. Folds are characteristically close or isoclinal and strike eastward. The post-Permian rocks appear to be less metamorphosed and less strongly deformed than the earlier rocks, and the Jurassic less than the Triassic. More than one epoch of diastrophism is therefore involved.
","largerWorkType":{"id":18,"text":"Report"},"largerWorkTitle":"Contributions to economic geology (short papers and preliminary reports), 1933","largerWorkSubtype":{"id":5,"text":"USGS Numbered Series"},"language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/b846A","usgsCitation":"Gilluly, J., Reed, J., and Park, C.F., 1933, Some mining districts of eastern Oregon: U.S. Geological Survey Bulletin 846, viii, 140 p., https://doi.org/10.3133/b846A.","productDescription":"viii, 140 p.","costCenters":[],"links":[{"id":399784,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_20512.htm"},{"id":93981,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/bul/0846a/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":170331,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/bul/0846a/report-thumb.jpg"}],"country":"United States","state":"Oregon","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -117.6290,\n 44.4129\n ],\n [\n -117.548,\n 44.4129\n ],\n [\n -117.548,\n 44.4519\n ],\n [\n -117.6290,\n 44.4519\n ],\n [\n -117.6290,\n 44.4129\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4aefe4b07f02db6914de","contributors":{"authors":[{"text":"Gilluly, James","contributorId":51743,"corporation":false,"usgs":true,"family":"Gilluly","given":"James","email":"","affiliations":[],"preferred":false,"id":231417,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reed, J. C.","contributorId":75589,"corporation":false,"usgs":true,"family":"Reed","given":"J. C.","affiliations":[],"preferred":false,"id":231418,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Park, C. F. Jr.","contributorId":90277,"corporation":false,"usgs":true,"family":"Park","given":"C.","suffix":"Jr.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":231419,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":39324,"text":"pp175A - 1933 - Miocene foraminifera of the coastal plain of the eastern United States","interactions":[],"lastModifiedDate":"2013-06-13T13:51:19","indexId":"pp175A","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1933","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":331,"text":"Professional Paper","code":"PP","onlineIssn":"2330-7102","printIssn":"1044-9612","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"175","chapter":"A","title":"Miocene foraminifera of the coastal plain of the eastern United States","language":"English","publisher":"United States Government Printing Office","publisherLocation":"Washington, D.C.","doi":"10.3133/pp175A","usgsCitation":"Cushman, J., and Cahill, E., 1933, Miocene foraminifera of the coastal plain of the eastern United States: U.S. Geological Survey Professional Paper 175, 68 p., https://doi.org/10.3133/pp175A.","productDescription":"68 p.","costCenters":[],"links":[{"id":169902,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/pp/0175a/report-thumb.jpg"},{"id":268939,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/pp/0175a/report.pdf"}],"country":"United States","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -8.083333333333334,2.068055555555556 ], [ -8.083333333333334,0.0011111111111111111 ], [ -7.018055555555556,0.0011111111111111111 ], [ -7.018055555555556,2.068055555555556 ], [ -8.083333333333334,2.068055555555556 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b05e4b07f02db699c40","contributors":{"authors":[{"text":"Cushman, J.A.","contributorId":97162,"corporation":false,"usgs":true,"family":"Cushman","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":221308,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cahill, E.D.","contributorId":75207,"corporation":false,"usgs":true,"family":"Cahill","given":"E.D.","email":"","affiliations":[],"preferred":false,"id":221307,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":35439,"text":"b842 - 1933 - Metalliferous deposits of the greater Helena mining region, Montana","interactions":[],"lastModifiedDate":"2015-12-21T11:00:43","indexId":"b842","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1933","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":306,"text":"Bulletin","code":"B","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"842","title":"Metalliferous deposits of the greater Helena mining region, Montana","docAbstract":"The ore deposits described in this bulletin are distributed through a region of about 3,000 square miles surrounding the city of Helena, Mont. In general the surface of this region is mountainous, but it includes several large intermontane valleys. Large areas in the northern and eastern parts of the region sire underlain by sedimentary rocks of the Algonkian Belt series, and on the northeast and southwest the Belt rocks are overlain without any noticeable angular unconformity by Paleozoic and Mesozoic beds. Oligocene, Miocene, and possibly Pliocene sediments, composed chiefly of volcanic ash and land waste of local origin, occupy large areas in the intermontane valleys and lie unconformably upon Cretaceous and older rocks. A thin veneer of Pleistocene and Recent alluvium generally overspreads the Tertiary. In the extreme northern part of the region are large deposits of glacial drift that represent two stages of the Pleistocene.
The principal igneous body of the region is the northern part of the early Tertiary or late Cretaceous Boulder batholitb of quartz monzonite. The main exposure of this body occupies an area of nearly 1,200 square miles and extends southward beyond the limits of the particular region considered. Smaller areas of similar rocks are clustered around this exposure. Most of the exposures probably represent bodies that are connected in depth to form a single mass.
The late Cretaceous and older sedimentary rocks are involved in a series of northwestward-trending folds. Along the east side of the region overthrust faults related to the great Lewis overthrust of Glacier National Park cause Belt rocks to overlie rocks of Paleozoic and Mesozoic ages. Large normal faults occur near Marysville and faults of moderate displacement near Helena. The Tertiary beds are slightly deformed by folds and faults that are unrelated to the structure of the older rock. The geologic history of the region includes two contrasting periods, the earlier of which was characterized by the accumulation of marine sediments and the later by mountain building and erosion. The later period began with folding and elevation in late Cretaceous or early Eocene time, followed by overthrust faulting and the intrusion of the Boulder batholith. Next, there ensued a period of crustal stability, during which erosion reduced the region to a surface of low relief and cut away at least 10,000 feet of strata in the area north of Helena. In Oligocene, Miocene, and Pliocene (?) time sediments composed of land waste and volcanic ash were deposited, and this event was followed by warping and faulting that elevated the present mountains. During Pliocene and Pleistocene time the mountains were maturely dissected, and in middle and late Pleistocene time local glaciers formed in the higher mountains and large valley glaciers invaded the extreme northern part of the region.
The ore deposits include lodes and placers that have yielded gold, silver, lead, copper, and zinc to a value of at least $176,860,000. The placers were formed mostly during interglacial stages of the Pleistocene. They have been almost entirely exhausted. Most of the lodes are classified as regards age in two groups, an older and a younger. The older lodes are related in origin to the Boulder batholith or some of the neighboring intrusive granitic bodies and were probably formed during early Eocene time. The younger lodes were formed after dacite of probable Miocene age was erupted. They are possibly related in origin to some unexposed intrusive granitic rock.
For convenience in description the region is divided into three parts districts north of Helena, districts in the Belt Mountains, and districts south of Helena.
The districts north of Helena include a 50-mile stretch of the Continental Divide that forms a broad ridge surmounted with considerable areas of flat or gently sloping surface at a general altitude of 7,000 feet. Narrow valleys 1,000 to 2,000 feet deep are cut into this surface and lead out to the neighboring wide intermontane valleys. The area is underlain mostly by shale, sandstone, and limestone of the upper part of the Belt series. Beds of Paleozoic and Mesozoic age occur south of the Belt area and extend from Helena west and northwest. The igneous rocks of the area include diorite and gabbro sills and dikes of probable Cretaceous age, extrusive andesite that is probably Oligocene or Miocene, and stocks of quartz monzonite, granodiorite, and quartz diorite, probably of Oligocene or Miocene age.
The ore deposits of the northern districts are chiefly lodes that are valuable for gold and silver but contain some lead and copper. In the Ophir district bodies of gold and silver ore occur mainly in limestone near a body of quartz monzonite. In the Scratchgravel Hills and Grass Valley districts veins of gold quartz and veins containing lead-silver ore occur in quartz monzonite and in the adjoining metamorphic rocks. In the Austin district lodes containing gold; silver, lead, and copper are found in limestone near intrusive quartz monzonite. An unusual mineral in one of these lodes is corkite, a hydrous sulphate of lead containing arsenic. A small stock of quartz diorite in the Marysville district has invaded and domed Belt rocks. Marginal and radial fractures formed during the cooling and contraction of the igneous body became the receptacles of gold and silver veins, one of which, the Drumlummon, has produced $16,000,000. The veins filled open fractures and are characterized by a gangue of platy calcite and quartz. Lodes in Towsley Gulch in the western part of the district contain lead in addition to gold. In the Gould district a small stock of the granodiorite has invaded the Belt rocks and caused the deposition of veins similar to those near Marysville. In the Heddleston district lodes valuable for gold, silver, lead, and copper occur in Belt sedimentary rocks and diorite, some of them associated with porphyry dikes. In the Wolf Creek district veins in Belt rocks have produced copper ore composed mainly of chalcopyrite or chalcopyrite and tennantite accompanied by pyrite and a gangue of quartz and barite.
Placer deposits along the western slope of the Belt Mountains have produced $17,500,000 in gold. Sapphires were formerly obtained from some of these deposits. The central part of the Belt Mountains is a plateaulike area considered to be the remnant of a surface produced by erosion during Tertiary time. This surface was elevated and has been deeply trenched by narrow, transverse valleys that are bordered with remnants of low terraces in which most of the placer deposits occur. Most of the western slope of the mountains is underlain by sedimentary rocks of the Belt series. At the foot of the mountains these give place to Paleozoic rocks, and these in turn are overlain unconformably in Townsend Valley by Tertiary and later deposits. The main structural feature is a great arch called the York anticline, which occupies most of the west side of the mountains. At the west foot of the mountains this fold is bordered by a series of small synclines that are tightly squeezed, faulted, and overturned as a result of pressure exerted from the west or southwest along a fracture described as the El Dorado overthrust On another fracture called1 the Scout Camp overthrust the Belt rocks composing the western slope of the mountains are thrust eastward over Paleozoic beds. Both faults are regarded as branches of the Lewis overthrust of Glacier Park. Igneous rocks that probably range in age from early Eocene to Pleistocene are widely but sparingly distributed.' They include sills and dikes of quartz dibrite, porphyry dikes, small stocks of quartz monzonite and quartz diorite, and surface flows of andesite and basalt.
The deposits in the Belt Mountains that are of most interest at the present time are lodes that are chiefly valuable for gold. Most of them are found in the vicinity of York and Confederate Gulch. Nearly all are small quartz veins formed along fractures in diorite dikes and stocks or on bedding planes in the adjoining Belt sedimentary rocks. An exception is the Golden Messenger, a replacement deposit of large size but low grade, formed along fractures in a quartz diorite dike. Other veins in the same dike belong to the rather uncommon class called ladder veins. Many of the small veins contain shoots and bunches of rich ore in their upper parts. Downward- enrichment in gold is indicated to have occurred in some of the veins near York that lie below an old erosion surface. Elsewhere the origin of the placer deposits from erosion o'f the lodes during interglacial stages of the Pleistocene is indicated. Lodes containing chalcopyrite occupy tension fractures in the Belt shales that were produced by lateral movements of the mass composing the mountain front.
In the districts south of Helena mining began with the discovery, on July 14, 1864, of rich placer deposits at the present site of the city of Helena, on Last Chance Creek. Since then the placer and lode deposits of these districts have produced metals worth $130,000,000 or more, of which about one-third was gold, the remainder chiefly lead and zinc. Sedimentary rocks ranging in age from Algonkian to Cretaceous underlie parts of the region, and other parts are underlain by a bedded series of andesite and latite tuffs, breccias, and flows. These rocks have been intruded and severely metamorphosed by the quartz monzonite of the Boulder batholith, the exposures of which occupy a large area. Rocks later than the intrusion of the batholith are chiefly a series of late Tertiary dacites and rhyolites.
The placers of the southern districts have been almost entirely worked out. The lodes have yielded metals worth $111,600,000, but many of them are still productive. They include veins and contact-metamorphic deposits. Some of the contact deposits contain copper ore, and others contain iron ore valuable for fluxing. The veins are of two ages. The older veins have yielded most of the metallic production of the region. Their ores in general are heavy sulphide aggregates composed mainly of galena, sphalerite, and pyrite. Arsenopyrite is generally present; tetrahedrite and chalcopyrite are less common. Many of the veins are distinguished from the usual type of ore body by the occurrence of abundant tourmaline. The, metals produced are chiefly silver, lead, gold, and zinc, with some copper. The younger veins are essentially precious-metal deposits. They are mainly fissure veins but include some disseminated deposits of low grade. They are widely distributed and include several productive bodies. A distinguishing feature is the occurrence in the gangue of cryptocrystalline quartz and lamellar calcite. A dominant eastward trend of the vein fractures of the older group indicates them to be tension cracks in the crust block lying west of the Lewis overthrust that were produced by stretching in a direction at right angles to the thrust.
No abstract available.
","largerWorkType":{"id":18,"text":"Report"},"largerWorkTitle":"Mineral resources of Alaska: Report on progress of investigations in 1930 (B836)","largerWorkSubtype":{"id":5,"text":"USGS Numbered Series"},"language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/b836D","usgsCitation":"Capps, S.R., and Moffit, F.H., 1933, The eastern portion of Mount McKinley National Park. The Kantishna district. Mining development in the Tatlanika and Totatlanika basins: U.S. Geological Survey Bulletin 836, Report: 130 p.; 1 Plate: 38.40 × 24.64 iniches, https://doi.org/10.3133/b836D.","productDescription":"Report: 130 p.; 1 Plate: 38.40 × 24.64 iniches","costCenters":[],"links":[{"id":399854,"rank":4,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_20499.htm"},{"id":177130,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/bul/0836d/report-thumb.jpg"},{"id":114651,"rank":400,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/bul/0836d/plate-4.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":114650,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/bul/0836d/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"country":"United States","state":"Alaska","otherGeospatial":"Kantishna district, Mount McKinley National Park, Tatlanika and Totatlanika basins","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -151.171875,\n 62.492027730426905\n ],\n [\n -148.11767578125,\n 62.492027730426905\n ],\n [\n -148.11767578125,\n 64.03374392176401\n ],\n [\n -151.171875,\n 64.03374392176401\n ],\n [\n -151.171875,\n 62.492027730426905\n ]\n ]\n ]\n }\n },\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -142,\n 64.8\n ],\n [\n -141,\n 64.8\n ],\n [\n -141,\n 65.5\n ],\n [\n -142,\n 65.5\n ],\n [\n -142,\n 64.8\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b08e4b07f02db69b6ea","contributors":{"authors":[{"text":"Capps, Stephen Reid","contributorId":95041,"corporation":false,"usgs":true,"family":"Capps","given":"Stephen","email":"","middleInitial":"Reid","affiliations":[],"preferred":false,"id":246086,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Moffit, Fred Howard","contributorId":18815,"corporation":false,"usgs":true,"family":"Moffit","given":"Fred","email":"","middleInitial":"Howard","affiliations":[],"preferred":false,"id":246085,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70221747,"text":"70221747 - 1933 - Further remarks on the Cripple Creek Volcano, Colorado","interactions":[],"lastModifiedDate":"2021-06-30T18:02:56.774297","indexId":"70221747","displayToPublicDate":"1933-06-01T12:58:44","publicationYear":"1933","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1578,"text":"Eos, Transactions, American Geophysical Union","onlineIssn":"2324-9250","printIssn":"0096-394","active":true,"publicationSubtype":{"id":10}},"title":"Further remarks on the Cripple Creek Volcano, Colorado","docAbstract":"Structural evidence, particularly in the deeper mine‐workings, indicates that the volcano, which is of Tertiary age, was developed by explosive eruptions at a number of points along intersecting fissure‐systems that had been formed in pre‐Cambrian granite by east‐west compression, probably during the Laramide revolution. The volcanic breccia, which consists principally of phonolitic material, appears to fill several elongate or elliptical funnel‐shaped openings that coalesce upward and taper downward into roots. Local adjustments that followed the principal explosive eruptions developed fissure‐systems in the breccia parallel and transverse to the older fissure‐systems and permitted the intrusion of dikes and irregular masses of latite‐phonolite and syenite within the breccia mass. Mild regional readjustment, caused by compression in a nearly north‐south direction, ensued and reopened these fissure‐systems within and around the breccia mass. It was followed by the relatively widespread intrusion of dikes and irregular masses of phonolite. Local readjustment then recurred repeatedly, mainly along the master fissure‐systems, and was followed by three successive intrusions of alkaline basaltic dikes and finally by the formation of mineral veins.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/TR014i001p00243-1","usgsCitation":"Loughlin, G.F., 1933, Further remarks on the Cripple Creek Volcano, Colorado: Eos, Transactions, American Geophysical Union, v. 14, no. 1, p. 243-243, https://doi.org/10.1029/TR014i001p00243-1.","productDescription":"1 p.","startPage":"243","endPage":"243","costCenters":[],"links":[{"id":386907,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado","city":"Cripple Creek","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -105.31219482421875,\n 38.70480271154007\n ],\n [\n -105.00732421875,\n 38.70480271154007\n ],\n [\n -105.00732421875,\n 38.78620445725866\n ],\n [\n -105.31219482421875,\n 38.78620445725866\n ],\n [\n -105.31219482421875,\n 38.70480271154007\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"14","issue":"1","noUsgsAuthors":false,"publicationDate":"2014-08-18","publicationStatus":"PW","contributors":{"authors":[{"text":"Loughlin, G. F.","contributorId":8428,"corporation":false,"usgs":true,"family":"Loughlin","given":"G.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":818606,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70220433,"text":"70220433 - 1933 - Fluctuations of water‐surface in observation‐wells and at stream gaging‐stations in the Mokelumne Area, California, during the earthquake of December 20, 1932","interactions":[],"lastModifiedDate":"2021-05-13T13:04:33.295378","indexId":"70220433","displayToPublicDate":"1933-05-13T07:55:11","publicationYear":"1933","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1578,"text":"Eos, Transactions, American Geophysical Union","onlineIssn":"2324-9250","printIssn":"0096-394","active":true,"publicationSubtype":{"id":10}},"title":"Fluctuations of water‐surface in observation‐wells and at stream gaging‐stations in the Mokelumne Area, California, during the earthquake of December 20, 1932","docAbstract":"On December 20, 1932, much of the western United States felt a pronounced earthquake‐shock which caused noticeable fluctuations of the water‐surface in several observation‐wells and at two stream gaging‐stations in the Mokelumne Area, central California. These effects of the earthquake are reported briefly in this paper.
According to Dr. Byerly (personal communication, February 9, 1933), in charge of the seismograph‐station of the University of California at Berkeley, the earthquake‐ vibrations at that place began at 10h 11m 00s p.m., Pacific Standard Time, December 20, 1932, and continued three hours on the records of his most sensitive instruments. He reports further that the maximum double amplitude of the Earth‐motion at Berkeley was of the order of two mm and that the north‐south and east‐west components of the amplitude were approximately equal. In the Mokelumne Area, which centers about the City of Lodi, 57 miles north 70° east from the seismograph‐station at Berkeley, the pronounced initial Earth‐shock caused chandeliers to sway, upset some bric‐a‐brac, and in at least one building opened a few cracks in the interior plastering. At Stockton, 15 miles south of Lodi, the glass of at least one display‐window in a shop was cracked.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/TR014i001p00471","usgsCitation":"Piper, A., 1933, Fluctuations of water‐surface in observation‐wells and at stream gaging‐stations in the Mokelumne Area, California, during the earthquake of December 20, 1932: Eos, Transactions, American Geophysical Union, v. 14, no. 1, p. 471-475, https://doi.org/10.1029/TR014i001p00471.","productDescription":"5 p.","startPage":"471","endPage":"475","costCenters":[],"links":[{"id":385604,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","otherGeospatial":"Mokelumne Area","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -120.48431396484375,\n 38.31041334882078\n ],\n [\n -119.7015380859375,\n 38.31041334882078\n ],\n [\n -119.7015380859375,\n 38.72730457751627\n ],\n [\n -120.48431396484375,\n 38.72730457751627\n ],\n [\n -120.48431396484375,\n 38.31041334882078\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"14","issue":"1","noUsgsAuthors":false,"publicationDate":"2014-08-18","publicationStatus":"PW","contributors":{"authors":[{"text":"Piper, Arthur M.","contributorId":65060,"corporation":false,"usgs":true,"family":"Piper","given":"Arthur M.","affiliations":[],"preferred":false,"id":815532,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70188621,"text":"70188621 - 1933 - Sixth report of the United States Geographic Board: 1890 to 1932","interactions":[],"lastModifiedDate":"2017-06-19T11:50:39","indexId":"70188621","displayToPublicDate":"1933-01-01T00:00:00","publicationYear":"1933","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":1,"text":"Federal Government Series"},"seriesTitle":{"id":5429,"text":"Report of the United States Geographic Board","active":false,"publicationSubtype":{"id":1}},"seriesNumber":"6","title":"Sixth report of the United States Geographic Board: 1890 to 1932","docAbstract":"This report contains, with the exception of a comparatively small number, all the decisions rendered by the board from its organization in 1890 through June, 1932, and supersedes all previous reports. Not included in this report are such decisions as have either been vacated, or, being revised, have been replaced by new decisions listed under the revised name or spelling.
Several thousand earlier decisions for features and places in the United States, Alaska, and the Philippine Islands have been amplified, brought up to date, and made to agree in form and content with the decisions rendered in recent years.
So great have been the changes since 1914 in the geographic nomenclature of the Eastern Hemisphere that the board deemed it advisable to vacate all the names as given in the fifth and earlier reports for places and features not within the United States and its outlying territories and possessions. In place of these a new list has been drawn up comprising some 2,500 of the more important names, which are in accord with the changes which have taken place since the World War. These new decisions, printed in 1932 in a separate pamphlet with the title, \"First Report on Foreign Geographic Names,\" have been consolidated in this volume with domestic names in one alphabetical arrangement.
In the fifth report the Philippine and the Hawaiian names were each separately listed at the close of that volume. In the present report, however, they are interspersed alphabetically with other names.
The Board welcomes the views of map makers and of all others who are interested in geographic nomenclature as to how its decisions may be made of greater service.
","language":"English","publisher":"U.S. Government Printing Office","publisherLocation":"Washington D.C.","usgsCitation":"U.S. Government Printing Office, 1933, Sixth report of the United States Geographic Board: 1890 to 1932: Report of the United States Geographic Board 6, ix, 834 p.","productDescription":"ix, 834 p.","numberOfPages":"844","costCenters":[],"links":[{"id":342639,"rank":2,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/unnumbered/70188621/report-thumb.jpg"},{"id":342638,"rank":1,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/unnumbered/70188621/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5948e2a8e4b062508e354c86"} ,{"id":70159324,"text":"70159324 - 1932 - Ground water supplies of the Camden area, New Jersey","interactions":[],"lastModifiedDate":"2020-04-30T14:33:02.555607","indexId":"70159324","displayToPublicDate":"2015-05-04T08:00:00","publicationYear":"1932","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":2,"text":"State or Local Government Series"},"seriesNumber":"39","title":"Ground water supplies of the Camden area, New Jersey","docAbstract":"This report is one of several setting forth the results of investigations as to the safe yield of the principal water-bearing formations in certain parts of New Jersey, carried on cooperatively by the New Jersey Department of Conservation and Development and the United States Geological Survey. Other areas in which similar studies have been made are the Atlantic City area; the Asbury Park area; the Runyon area, including the Perth Amboy well field; the area embracing the well fields of the Commonwealth-Water Co., the East Orange Water Department, and other municipalities near the Passaic River in the vicinity of Chatham; and the Garfield Water Department well field and those of several industries in the vicinity of East Paterson.
\nThe results of the study in the Camden area are of value for several reasons. The greater part of the water supply of Camden comes from wells in three fields with an estimated capacity of about 30 million gallons a day, distribute1 over a triangular area of less than one square mile. This is one of the largest developments of ground water in so small an area in the United States. During the investigation a number of new wells were drilled in this area, and the type of wells and methods of pumping were changed, and observations were possible that otherwise could seldom be obtained under such favorable circumstances. As a result of the building of the new bridge across the Delaware River between Philadelphia and Camden there has been a considerable increase in population and in consumption of water in the Camden area, and this investigation is valuable in showing the extent to which further development of ground water is possible.
\nThe observations on which the report is based were made in the period from July 1, 1923, to the date of writing the report, in the early part of 1928.1 The continuing observations have been confined essentially to the well fields of the Camden Water Department. Certain data in regard to other well fields within a radius of 10 miles of Camden, collected by F. Clark Rule under the direction of the writer in the summer of 1923, and other data obtained from the files of the Department of Conservation and Development are also included in so far as they bear on the problems under consideration. The City of Camden has cooperated heartily through C. P. Sherwood, formerly director of the Department of Streets and Public Improvements, his successor, W. D. Sayrs, Jr., James H. Long, maintenance engineer of the Water Department, and David B. Owen, chief engineer of the Morris pumping station. Much valuable information has been furnished by the Layne-New York Co., which, during the period of the investigation, replaced nearly all the old-type wells of the Camden system with those of the most modern type. The investigation was under the immediate supervision of H. T. Critchlow, then chief of the Division of Waters of the Department of Conservation and Development, and O.E. Meinzer, geologist in charge of the Division of Ground Water of the United States Geological Survey. The late Dr. M. W. Twitchell, assistant State geologist, was consulted on phases relating to the stratigraphy. A number of analyses of water have been made by C. S. Howard, of the United States Geological Survey, and advice in regard to problems arising from the mineral character of the water has been given by W. D. Collins, chemist in charge of the Division of Quality of Water of the same organization. Thanks are also due to those of the other water departments and private well owners in the area who have furnished information.
","language":"English","publisher":"New Jersey Department of Conservation and Development","collaboration":"In cooperation with the United States Geological Survey, Division of Ground Water","usgsCitation":"Thompson, D., 1932, Ground water supplies of the Camden area, New Jersey, iv, 80 p.","productDescription":"iv, 80 p.","numberOfPages":"86","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":310300,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/70159324.jpg"},{"id":311211,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/unnumbered/70159324/report.pdf","text":"Report","linkFileType":{"id":1,"text":"pdf"},"description":"Report"}],"country":"United States","state":"New Jersey","county":"Camden County","city":"Camden","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -75.07095336914062,\n 39.9811978499522\n ],\n [\n -75.09550094604492,\n 39.97435761238716\n ],\n [\n -75.13172149658203,\n 39.959490889505346\n ],\n [\n -75.13687133789061,\n 39.93659244591381\n ],\n [\n -75.13292312622069,\n 39.92290236029078\n ],\n [\n -75.13275146484375,\n 39.907761097366105\n ],\n [\n -75.1332664489746,\n 39.89485546645595\n ],\n [\n -75.10374069213867,\n 39.893275018082456\n ],\n [\n -75.03250122070312,\n 39.910657945728\n ],\n [\n -75.03644943237305,\n 39.94172552213356\n ],\n [\n -75.05430221557617,\n 39.973436758888674\n ],\n [\n -75.05773544311523,\n 39.980145550276994\n ],\n [\n -75.07095336914062,\n 39.9811978499522\n ]\n ]\n ]\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5628b734e4b0d158f5926c25","contributors":{"authors":[{"text":"Thompson, David G.","contributorId":8443,"corporation":false,"usgs":true,"family":"Thompson","given":"David G.","affiliations":[],"preferred":false,"id":578012,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":4616,"text":"wsp682 - 1932 - Surface water supply of the United States, 1929, Part II, South Atlantic slope and eastern Gulf of Mexico basins","interactions":[],"lastModifiedDate":"2012-02-02T00:05:40","indexId":"wsp682","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1932","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":341,"text":"Water Supply Paper","code":"WSP","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"682","title":"Surface water supply of the United States, 1929, Part II, South Atlantic slope and eastern Gulf of Mexico basins","language":"ENGLISH","publisher":"U.S. Govt. Print. Off.,","doi":"10.3133/wsp682","usgsCitation":"Water Resources Division, U.S. Geological Survey, 1932, Surface water supply of the United States, 1929, Part II, South Atlantic slope and eastern Gulf of Mexico basins: U.S. Geological Survey Water Supply Paper 682, vi, 178 p. ;23 cm., https://doi.org/10.3133/wsp682.","productDescription":"vi, 178 p. ;23 cm.","costCenters":[],"links":[{"id":139216,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wsp/0682/report-thumb.jpg"},{"id":31673,"rank":300,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wsp/0682/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4afee4b07f02db697964","contributors":{"authors":[{"text":"Water Resources Division, U.S. Geological Survey","contributorId":128075,"corporation":true,"usgs":false,"organization":"Water Resources Division, U.S. Geological Survey","id":528310,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":39321,"text":"pp171 - 1932 - Geology and ore deposits of the Pioche district, Nevada","interactions":[],"lastModifiedDate":"2015-12-21T11:21:43","indexId":"pp171","displayToPublicDate":"1994-01-01T00:00:00","publicationYear":"1932","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":331,"text":"Professional Paper","code":"PP","onlineIssn":"2330-7102","printIssn":"1044-9612","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"171","title":"Geology and ore deposits of the Pioche district, Nevada","docAbstract":"LOCATION AND SURFACE FEATURES
The Bristol Range, Highland, and Ely Range quadrangles make up the larger part of a. rectangular area 35 miles north and south by 24 miles east and west, which lies 19 miles west of the Nevada-Utah line and about 250 miles southwest of Salt Lake City. The district lies within the Great Basin, a semiarid region of alternating mountain ranges and intermontane plains floored largely by outwash from the mountains.
The plain, which slopes away from the ranges, stands between 4,700 and 6,000 feet above the sea. The Bristol and Highland Ranges, which are separated only by a low gap, form an almost continuous north-south range that rises about 2,500 feet above the highest part of the surrounding plain, to general altitudes of 8,000 to 9,000 feet, though the highest point, Highland Peak, reaches 9,395 feet. A lower range, the Ely Range, with a northwesterly trend, lies farther east and nearly in touch with the Bristol-Highland Range. The town of Pioche lies midway on the. eastern foot of the Ely Range.
ROOKS OF THE PIOOHB REGION
The rocks of the ranges are Paleozoic sediments, Tertiary (?) lavas and intrusive rocks, and Pliocene (?) tuffs.
The Paleozoic sediments have a total thickness of nearly 18,000 feet. Over 8,000 feet of the Cambrian has been measured without reaching its base. The lowest Cambrian formation is a quartzite, of which only the upper 1,500 feet is exposed, and this is followed by 1,200 feet of shale, 400 feet of limestone, aoid 150 feet of shale. Above this second shale the upper three-fourths of the Cambrian consists of limestone and dolomitic limestone. It is in the quartzite and in the limestone interbedded in and bounding the shales that the main ore bodies of the district have been found. Above the Cambrian comes 1,795 feet of Ordovician limestone, with some interbedded dolomite and with a 50-foot quartzite a, third of the way down from the top; 75 feet of Silurian dolomite; 3,000 feet of Middle Devonian dolomite with thin interbedded quartzite near the top, followed by 550 feet of Upper Devonian limestone; 3,775 feet of Mississippian limestone with a heavy quartzitic sandstone just below the middle; then, at the top of the series, 700 feet of Pennsylvania n limestone.
The Paleozoic formations are tilted, bent, and faulted, but sharp folding is extremely rare. Dips between 10° and 30° are common, but there are few greater than 40°. The rocks are cut by many large and innumerable small normal faults, which in many parts of the area are difficult to recognize because they cut thick formations of similar rocks. A large thrust fault occurs along the west side of the Bristol-Highland Range.
A thick series of lavas with interbedded tuffs lies along the flanks of the ranges and makes up a large part of the hilly northwest corner of the Bristol quadrangle. The lavas lie unconformably on the Paleozoic sediments and consist mainly of dacite, latite, and andesite, with some basalt and a little rhyolite. About 6,000 feet of lavas and tuffs were measured in Condor Canyon, near the south end of the Ely Range. The age of the lavas is not sharply fixed; they may be early Tertiary or even late Mesozoic. It is not unlikely that they are the result of volcanic action extending over a long period. The lavas are tilted and faulted, though their average dip is less than that of the Paleozoic sediments.
At Blind Mountain, on the west side of the Bristol Range, stocks of quartz monzonite and dikes of similar composition cut an infaulted block consisting of sediments, chiefly Devonian, and lavas. Both the sediments and the lavas are metamorphosed, and a belt of marked metamorphism extends south along the west base of the Bristol-Highland Range for several miles. The quartz porphyry dikes of the region, including those near Pioche, are believed to have come in at the same time.
The plain west of the Bristol-Highland Range is a. valley of interior drainage floored with outwash from the mountains, coarser near the range but finer and making a clay flat along the west side of the Bristol Range and Highland quadrangles. The valley east of the Bristol-Highland Range, however, has outside drainage by way of Meadow Valley to the Virgin and Colorado Rivers. The stream in upper Meadow Valley and its tributaries have cut through the surface wash from the mountains and laid bare several hundred feet of white, yellow, and red water-laid Pliocene tuffs that lie in nearly the position in which they were laid down. This erosion has developed a striking badland topography in the Pliocene beds.
HISTORICAL SUMMARY
The general succession of events may be summarized as follows:
1. Sedimentation during most of Paleozoic time from Cambrian to Pennsylvanian.
2. Uplift, slight warping, and erosion.
3. Volcanism of perhaps late Mesozoic or early Tertiary time, producing lavas and tuffs. This period of volcanism may have lasted a long time and spanned one or more of the epochs of faulting.
4. Tilting and normal faulting.
5. Thrust faulting.
6. Quartz monzonite intrusions at Blind Mountain.
7. Normal block faulting of the Basin Range type.
8. Erosion of the faulted blocks to maturity and to essen-. tially the topography of to-day.
9. Outbursts of volcanic ash, probably in late Pliocene time, and the deposition of several hundred feet of water-laid tuffs in the valleys.
10. In Meadow Valley, valley cutting, which has produced a badland topography in the soft Pliocene tuffs and canyons where the streams cross the harder Paleozoic limestones.
ECONOMIC GEOLOGY
The Pioche district during four years in the early seventies was second only to the Comstock district in output of silver. The bonanza ore of those stirring times came from fissure veins in the Prospect Mountain quartzite, of Lower Cambrian age. In recent years the main interest has shifted to the bedded replacement deposits of silver-bearing lead-zinc sulphide ore occurring in the limestone members of the Pioche shale a type of ore body which was discovered accidentally during the prospecting of the fissure veins.
The ore deposits of the district comprise three groups (1) silver-bearing fissure veins in quartzite; (2) silver-bearing mineralized granite porphyry; (3) replacement deposits in limestone and dolomite. All of them appear to have been formed at about the same time, in the epoch of mineralization that occurred shortly after the intrusion of the granitic rocks and their allied dikes of granite porphyry and lamprophyre.
The entire present output of the district is coming from the replacement deposits in limestone and dolomite, but exploratory work is still in progress on the fissure veins and mineralized porphyry.
The replacement deposits include both replacement fissure veins and stratiform (\"bedded\") replacement deposits.
The replacement fissure veins dip steeply and cut across the bedding of the carbonate rocks in which they are inclosed. They are thoroughly oxidized, as deep at least as 1,100 feet, for on none of them have the mine workings penetrated to water level, and they are highly manganiferous and limonitic and low in silica. At-certain horizons stratiform replacement deposits extend out as lateral branches from the fissure veins. Deposits of this kind occur mainly in the Mendha limestone, Highland Peak limestone, and Lyndon limestone. The stratigraphic range is therefore at least 5,500 feet, and as some of the fissure veins extend down through the underlying Pioche shale the indicated range may exceed 6,500 feet. The most notable representatives of the replacement fissure veins are at the Bristol mine, where they yield silver-bearing copper-leadzinc ores. So far unique among the ore bodies of the district is the pipe of wad and pyrolusite ore at the Jackrabbit mine, the periphery of the pipe consisting of a girdle of extraordinarily coarse white calcite spar produced by the recrystallization of the surrounding limestones.
The stratiform replacement deposits that are attracting most attention occur at the intersections of steep fissures with the limestone members of the Pioche shale. In recent years the \" bedded \" ore of the Combined Metals mine has been of main interest. The ore is essentially a.n intimate intergrowth of pyrite, sphalerite, and galena. Although above water level, the ore is unoxidized. It extends on both sides of the mineralizing fissure as far as 100 feet. At the Prince mine ore beds were formed at seven successively higher horizons in the Pioche shale and the overlying Lyndon and Highland Peak limestones. The ore \" beds \" above water level in the Prince mine are thoroughly oxidized and consist of manganese-iron oxides low in silver, lead, and zinc. About 800,000 tons of ore carrying 2.5 to 3 ounces of silver to the ton, 3 per cent of lead, 35 per cent of iron, and 15 per cent of manganese has been shipped. The Prince mine was in 1915-1918 the premier producer of lead in Nevada. The ore \" bed \" that occurs here below water level consists of sphalerite, galena, and pyrite in a gangue of manganosiderite and minor quartz. This is the only locality in the district in which the primary source of the abundant oxidized manganese minerals (wad, pyrolusite, and braunite) has so far been found.
Some of the stratiform ore bodies the ore beds, as they are locally called were formed adjacent to exceedingly insignificant-looking fissures; and this dependence on inconspicuous mineralizing fissures is beyond doubt one of the most impressive features in the geology of the district. It opens the possibility that there may be many other bedded deposits which, like the Combined Metals ore bed, do not crop out. To find these ore bodies will be difficult, but their discovery will be aided primarily by applying skillfully a knowledge of the geologic column and by determining the faulting that has disturbed or changed the normal sequence of the strata.