Bulletin of the United States Geological SurveyThe Survey., 1908 - Geology |
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Common terms and phrases
Alcalde appear Avenal axis barrels basal base beds of blue Big Blue Big Tar Canyon blue sand California Canoas Chico Coalinga anticline Coalinga district Coalinga field coarse Cretaceous deposits Diablo Range Eastside field Etchegoin formation exposed feet thick flank fossiliferous fossils Gatos Creek geology Glycymeris zone gravel gray sand interbedded Jacalitos Creek Jacalitos formation Kettleman Hills Knoxville-Chico Kreyenhagen field Kreyenhagen Hills layers Los Gatos Creek McLure Valley miles monocline north of Coalinga northern northwest occurs Oil City Oil Company oil sands oil zone outcrop overlain overlying Paso Robles Paso Robles formation pebbly sand Pecten petroleum Pleasant Valley prominent Pyramid Hills Reef Ridge region rocks San Joaquin Valley sandstone sandy clay Santa Margarita shale siliceous shale soft southeast southern southwest strata structure summit syncline tar sands Tejon Eocene tion unconformity upper Miocene uppermost Vaqueros lower Miocene Waltham Creek water sand Westside
Popular passages
Page 61 - Robles formation does not come in contact with the oil-bearing formations and contains no traces of oil. Over most of the area in which it occurs it is separated by so great a thickness of deposits from the productive zones that its mere presence is usually sufficient to indicate the inaccessibility of the oil.
Page 55 - The Etchegoin formation is nowhere within the Coalinga district known to contain any petroleum, but like the Jacalitos it has an important relation to the question of accessibility of the oil. Some wells in the Coalinga field pass through a considerable portion or the whole of this formation before reaching the Jacalitos or lower formations. All wells drilled around the edge of Pleasant Valley, or on Anticline Ridge, or in the Kettleman Hills will have to pass through this formation, and its thickness...
Page 73 - The shales are composed in large part of the tests of foraminifera and diatoms, and a smaller number of other organisms, in such abundance as fully to warrant the assumption that the animal and vegetable material that must have been contained in them when deposited was adequate for furnishing a quantity of hydrocarbons and other compounds more than equivalent to the quantity of petroleum found in this field...
Page 37 - ... shales. Santa Margarita formation. The Santa Margarita formation is exposed in a strip along Reef Ridge and also in the East Side field. In the East Side field it consists of a basal member of about 300 feet of light-gray fine sand and clay that have a light bluish tinge when moistened. This member is overlain by the TamiosOma zone, which comprises a thickness of about 175 feet of fossiliferous, fine, medium-grained, and coarse, usually gray sand and minor amounts of conglomerate. This in turn...
Page 8 - ARNOLD, RALPH, and ANDERSON, ROBERT, Geology and oil resources of the Santa Maria oil district, Santa Barbara County, Cal.
Page 23 - The most important and distinctive feature of the formation is the predominantly fine-grained nature of the beds toward the top as compared with those below. The Tejon comprises a thickness of from 1,400 to 2,300 feet where exposed most completely, the upper half of which is made up of thin beds of whitish and purplish, siliceous, argillaceous, and locally calcareous shale which is easily recognizable and which lends individuality to the formation. The lowermost few hundred feet are of variable sandy...
Page 48 - The lower portion of the formation is composed largely of beds of compact coarse and fine bluish-gray sand alternating with zones of pebbly sand, fine gray sand, and some clay, with occasional more hardened beds. The clay increases toward the upper part of the formation, being interbedded with unconsolidated light-gray sand that spreads over the surface and obscures the structure. The formation occurs in the low hills bordering the valley and passes beneath the alluvium of the floor. The Etchegoin...
Page 70 - The anticlinal theory of oil accumulation assumes that the oil, being of less specific gravity, rises above the water present in porous rocks and collects at the highest possible points in upward folds, being there confined by impervious strata arching over the folds. The presence of water, according to this theory, is considered as fundamentally necessary for the carrying out of the process of accumulation in anticlines.
Page 8 - Preliminary report on the Santa Maria oil district, Santa Barbara County, Cal., by Ralph Arnold and Robert Anderson. 1907.
Page 74 - Coalinga district has been roughly divided into five fields or regions, and these into lesser subdivisions or areas. The major subdivisions are as follows: (1) The Oil City field, lying in Oil Canyon near the north end of the district; (2) the Eastside field, embracing the territory northeast of Oil Canyon and including Anticline, Ridge; (3) the Westside field, extending southeastward from Oil Canyon as far as Alcalde Canyon; (4) the Kreyenhagen field, which includes the Jacalitos and Kreyenhagen...