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Although the Golden fault dies out southeastward
<br />in the quadrangle, a belt of steeply dipping or over-
<br />turned strata continues to the southeast from the A4t.
<br />Carbon area (Scot[, 1962). This fact and structural
<br />relations such as [hose of the Lillie Pallaoro wells
<br />and wells in the Littleton quadrangle suggest chat a
<br />belt of complex structure may continue southward
<br />beyond the end of the fault for several miles in the
<br />subsurface,
<br />Minor faults,--Several short northwest-trending
<br />[auks, probablycontemporaneous with the Gold-
<br />en quadrangle, cut the Fort Hays Limestone Member of
<br />the Niobrara Formation in secs. 26 and 35, T. 4 S„
<br />R. 70 W. These faults dip about 50° S1V„ and all show
<br />an apparent displacement of the southwest block [o the
<br />northwest, They ev idently die out northwestward in [he
<br />Benton Shale, as they are not recognized in the hog-
<br />back of the Dakota Group; they also die out southeast-
<br />ward in [he shale of the Smoky Hill Shale Member,
<br />The contact of the Fountain with the underlying
<br />Precambrian rocks is offset by a few faults, and a
<br />fault along the contact near the mouth of Mount Ver-
<br />non Canyon is interred from a narrowing of the Foun-
<br />tain outcrop and from slickensided strata in aclay pit
<br />a few hundred feet north of U. S. Highway 40,
<br />Joints,--A-Joint pattern typical of the sedimentary
<br />terrane is well displayed in the large roadcut where
<br />Alameda Parkway crosses the Dakota hogback, There,
<br />a dominant joint set strikes N, 65° E, and dips verti-
<br />cally on the average, although the strike ranges from
<br />N. 50° E. to N, 70° E, and the dip from 80° S E. to about
<br />70° NW. A se[ of weaker joints strikes from due north
<br />to N, 30° W. and dips either 40°-60°SW, or 70°-80° NE,
<br />References Cited
<br />Berg, R. R., 1962, Subsurface interpretation of Golden
<br />Fault at Soda Lakes, Jefferson County, Colo-
<br />rado: Am, Assoc, Petroleum Geologists
<br />Bul]„ v, 46, p. 704-707.
<br />Johnson, S, H., 1930, Unconformiry in the Colo-
<br />rado Group in eastern Colorado: A:n. Assoc.
<br />Petroleum Geologists Bull„ v, l4, p. 769-
<br />794.
<br />1931, The paleontology of thr. Denver
<br />quadrangle, Colorado: Colorado Sci, Soc.
<br />P roc., v, l2, p, 355-378,
<br />LeRoy, L. W., 1946, Stratigraphy of [he Golden-
<br />Morrison area, Jefterson County, (:olorado:
<br />Colorado School Mines Quart., v. 41, no, 2,
<br />l15 p.
<br />Covering, T. S„ and Goddard, E. N.. 1938, I,aramide
<br />igneous sequence and differentiation in [he
<br />Front Range, Colo,: Geol, Soc. America
<br />Bull., v, 99, p. 35-68,
<br />Marsh, O. C„ 1877, Notice o[ anew and gigantic
<br />dinosaur; Am, Tour, Sci., 3d aer., v, l4,
<br />p, 87-68.
<br />Maughan, E. K„ and Wilson, R, F., 1960, Penn-
<br />sylvanian and Permian strata in southern
<br />Wyoming and northern Colorado, in Guide
<br />to the geology of Colorado: G~rol, Soc.
<br />America, Rocky Mtn, Assoc, Geologists, and
<br />Colorado Sci, Soc„ Denver, p. 34-92.
<br />Reichert, S. O., 1954, Geology of the Golden-Green
<br />Mountain area, Jefferson County, Colorado:
<br />Colorado School Mines Quan„ v, 99, no. 1,
<br />96 p.
<br />Scott, G. R. 1962, Geology of the Littleton quadrangle.
<br />Jefterson, Douglas, and Arapahoe Counties,
<br />Colorado; U. S. Ceol, Survey Bull. 1121-L,
<br />p. Ll-L53.
<br />Scott, G. R., and Cobban, W, A., 1959, So-called Hy-
<br />giene Group of northeastern Colorado [and
<br />Wyo, ~, in Rocky Mtn. Assoc. CeologiutsSym-
<br />posium on Cretaceous Rocks of (:olorado
<br />and adjacent areas, p. 124-131,
<br />Brown, R, W., 1943, Cretaceous-Tertiary boundary in Van Horn, Richard, 1957, Bedrock geology of ne Gold-
<br />the Denver Basin, Colorado: Geol. Soc, en quadrangle, Colorado: U. S. Geol. Survev
<br />America Bull„ v. 54, p. 65-86, Geol. Quad, Map GQ-103.
<br />Cobban, W,A„and Reeside, J.B., Jr„ 1952, Correlation
<br />of the Cretaceous formations of the Western
<br />interior of the United States: Geol. Soc,
<br />America Bu11„ v, 63, p. 1011-1043,
<br />Emmons, S, F.. Cross, Whitman. and Eldridge, G. H„
<br />1896, Geology of the Denver Basin, Color ado:
<br />U. S, Geol, Survey Mono, 27, 556 p,
<br />Hubert, J. F., L960, Petroloty of [he Fountain and
<br />Lyons Formations, Front Range, Colorado:
<br />Colorado School Mines Quart., v. 55, no, 1,
<br />242 p.
<br />WaagA, K. M„ 1955, Dakota group in northern Front
<br />Range foot hills, Colorado: U. S. Geol. Sur-
<br />vey Prof, Paper 274-B, p, 15-51,
<br />Waldschmid[, W, A., 1939, The Table Mountain lavas
<br />and associated igneous rocks near Golden,
<br />Colo,: Colorado School Mines Quart., v, 34,
<br />na. 3, 62 p.
<br />Waldschmidt, W, A., and LeRoy, L, W., 1944, Recon-
<br />sideration of the Morrison tormaticn in the
<br />type area, Jefferson County, Colorado: Geol.
<br />Soc, America Bull„ v. 55, p, 1097-1113.
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