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Pennsylvanian Rocks and Fusulinids

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Descriptions of Measured Sections

Section P-9. Sheep Mountain Canyon, Utah

On Manila-Vernal road, 12 miles by highway from Manila, Utah. Base of section begins at base of north-dipping limestone, west side highway just north of small tributary canyon and about 100 yards north of vertical limestone. Section extending up cliff to north and along highway. Located mainly in sec. 9, T. 2 N., R. 19 E., Daggett County, Utah. (See Figs. 3, 10).

8.5 (67) Limestone, blue, brittle and hard; abundant blue chert masses.
10.0 (66) Limestone, gray to bluish gray, highly fossiliferous; massively bedded with chert nodules; makes prominent band along cliff; weathers to slabby beds at base.
68.0 (65) Sandstone, fine-grained, cross-bedded, porous, calcareous, faces show thin lamination; weathers white in upper 40 feet; softer in upper part.
5.0 (64) Siltstone, highly arenaceous, dolomitic; weathers into thin fissile sheets; weathers bright yellow.
7.0 (63) Dolomite, yellow, arenaceous; weathers slabby.
51.0 (62) Sandstone, buff, cross-bedded; weathers to thin slabby beds.
6.0 (61) Limestone, bluish gray; thin bands and nodules of light-gray chert; abundant fusulinids.
32.4 (60) Sandstone, buff, fine-grained, glistening, porous, cross-bedded.
9.0 (59) Limestone, bluish gray, cherty; highly fossiliferous.
34.0 (58) Sandstone, buff, cross-bedded; forms cliff.
3.5 (57) Limestone, highly nodular; nodules imbedded in yellow to greenish shale; more massive and cherty in upper one foot.
4.5 (56) Limestone, sandy, yellowish gray where examined; contains prominent beds of light-gray chert; apparent irregular contact with sand below.
6.0 (55) Sandstone, shaly at base, buff, medium- to fine-grained; weathers yellow.
48.6 (54) Sandstone, buff, fine-grained, highly cross-bedded; upper 5 feet weathers more easily and is light gray.
0.5 (53) Shale, yellow at bottom, bluish gray at top.
3.0 (52) Sandstone, highly calcareous and fossiliferous; more highly calcareous in upper part.
15.5 (51) Sandstone, light gray, locally buff; weathers light buff to white; forms prominent light band on side of cliff.
32.0 (50) Sandstone, buff to light gray, cross-bedded, glistening, massively bedded.
5.0 (49) Sandstone, buff, highly cross-bedded, hard; weathers dark brown on surface; forms prominent bed along cliff.
3.0 (48) Limestone, light gray, fossiliferous; contains fusulinids; locally entirely replaced by light-gray chert.
24.8 (47) Sandstone, light gray to buff, fine-grained, cross-bedded, glistening.
3.0 (46) Sandstone, highly calcareous, cross-bedded, buff, glistening; contains nodular chert.
0.8 (45) Limestone, blue-gray to gray, hard; thinly laminated in appearance.
2.8 (44) Limestone, bluish gray to slightly brown, soft marly zones; highly fossiliferous; fusulinids abundant.
51.0 (43) Sandstone, light gray to buff, fine-grained, hard, cross-bedded, siliceous; contains soft light-gray streaks and abundant small limestone concretions in soft streaks; upper 5 to 8 feet weathers easily; forms bench.
0.5 (42) Sandstone, yellow, fine-grained.
2.5 (41) Sandstone, highly calcareous; contains lenses of lime, hard, sub-quartzitic.
1.4 (40) Limestone, finely nodular; interbedded with yellow shale.
3.6 (39) Sandstone, highly calcareous; stringers of chert.
0.8 (38) Limestone, bluish gray, highly sandy, fossiliferous, highly cherty; weathers bluish gray.
23.0 (37) Sandstone, light gray to tan, cross-bedded; sub-quartzitic on fresh breaks.
0.6 (36) Sandstone, soft; weathers yellowish.
7.5 (35) Sandstone, light gray, fine-grained, massive; weathers buff; thin shale break at base.
10.5 (34) Sandstone, calcareous, scattered chert bands, sub-quartzitic; chert up to 1 foot thick; appears as limestone on some fresh surfaces.
7.8 (33) Sandstone, yellow to buff, fine-grained; weathers bright yellow.
3.5 (32) Shale, dark purplish red, highly silty; scattered light-gray spherical concretionary masses; sharp contact with bed above.
0.5 (31) Chert, light gray to red.
0.5 (30) Sandstone, dark red, argillaceous, fine-grained.
1.0 (29) Limestone, light gray to tan, slightly sandy and cherty.
6.5 (28) Sandstone, purplish, calcareous; light-gray chert stringers; red in upper 2 feet.
10.0 (27) Sandstone, dark purplish red; soft and shaly in lower 5 to 6 feet; slightly resistant in upper 3 feet; contains abundant small spherical yellow to light-gray concretionary stains.
5.0 (26) Sandstone, red; lower 2 feet soft; upper 3 feet resistant; contains limestone concretions.
6.5 (25) Sandstone, red; contains concretions up to 1.5 feet in diameter and small pebbles in lower part; lower 2 feet recemented and looks like limestone on fresh cut.
3.0 (24) Sandstone, fine-grained; green to yellow and red on weathered slope; grading upward into limestone concretionary zone.
4.3 (23) Limestone, light gray, highly cherty (75 percent chert); fossiliferous in upper part.
3.8 (22) Limestone, light gray, crystalline, slabby; interbedded with hard yellow shale; fossiliferous.
4.0 (21) Limestone or sandstone, fossiliferous; fine-grained chert on weathered faces; abundant micro-cross-bedding.
0.8 (20) Limestone, light gray, coarsely crystalline, cherty; thin shale break at top and bottom.
1.5 (19) Limestone, light gray, light purple on fresh surface, coarsely crystalline, highly fossiliferous.
2.0 (18) Quartzite, light gray, glistening, cherty.
5.0 (17) Shale, yellow to light gray; weathers orange at top; contains nodules of yellow lime in upper part.
2.5 (16) Limestone, light gray to yellow, crystalline, slabby beds.
2.0 (15) Shale, purple; grading upward to yellow.
3.5 (14) Limestone, light gray, weathers lavender, brecciated in appearance, columnar fracture.
1.7 (13) Limestone, disseminated chert, yellow to white; weathers yellow; coarsely crystalline.
0.0 (12) Limestone, argillaceous, purple, prominent light-gray concretionary spherical stains; resistant in lower 1.5 feet; top 2 feet mainly purple shale; rubbly and nodular in upper part.
6.0 (11) Limestone, blue gray, conglomeratic in appearance, abundant chert masses (red to gray); lower 3 feet nodular with purple shale.
7.0 (10) Limestone, light yellowish gray to blue: about 50 percent banded chert.
5.0 (9) Shale, light yellow, fissile; alternating in upper part with thin bands of limestone.
3.5 (8) Shale, calcareous, purple, teeming with fossils; 0.5 feet chert at top; upper 2.5 feet resistant fossiliferous zone with chert band.
47.0 (7) Limestone, light bluish gray to light gray, massive to massively bedded; granular and glistening in lower 5 feet; scattered bands of yellow chert; thin shale 10 feet from top; abundant chert in top 3 feet.
87.7 (6) Limestone, blue to bluish gray, massively bedded; interbedded with thin blue to yellowish-gray shale.
62.3 (5) Limestone, blue gray to pearl gray, slightly cherty, massive beds; interbedded with highly fossiliferous shale layers; shale blue gray to red, more abundant in upper part.
15.6 (4) Limestone, blue gray to purple, highly fossiliferous, fossils silicified; upper 5 feet purple shale; lower part abundant yellowish-gray shale.
4.5 (3) Limestone, blue to lavender; thinly laminated on weathering; chert abundant; masses of red chert in upper part; highly fossiliferous in upper 0.2 feet.
19.0 (2) Limestone, gray to blue, massively bedded, beds 1 to 2 feet thick; abundant masses and irregular beds of blue to red chert; interbedded with gray shale.
44.0 (1) Limestone, bluish gray to gray, highly fossiliferous; beds 0.5 to 2 feet thick; interbedded with thin shale streaks; contains some disseminated chert; large masses of blue chert 10 feet below top and in upper 3 feet.
Note: Talus covered slope below Bed 1.

Section P-13, Juniper Mountain Canyon, Colorado

On north wall of canyon of Yampa River. Base of section begins about one-third of a mile east diversion dam and extending eastward along wall of canyon, about 2 miles west by north Juniper Springs. Top of section at east mouth of canyon. N2 sec. 18, T. 6 N., R. 94 W., Moffat County, Colo. (See Figs. 5, 7, and 9.)

22.5 (213) Limestone, bluish gray, fossiliferous; caps north bluff of east entrance of canyon; very irregular contact below.
37.5 (212) Sandstone, buff, fine-grained, cross-bedded. 20.0 (211) Limestone, bluish gray, massive, hard.
17.0 (210) Limestone, bluish gray, algal, thin even beds; becoming darker gray and brittle in upper part.
24.0 (209) Sandstone, buff, fine-grained, cross-bedded; weathers brown.
8.5 (208) Limestone, bluish gray, dense, hard; scattered brown chert at top.
9.0 (207) Sandstone, buff, fine-grained; thin slabby beds.
12.0 (206) Limestone, bluish gray, highly algal, thin-bedded; lower 3.5 feet composed almost entirely of fusulinids.
21.0 (205) Limestone, bluish gray, dense and hard; common dark chert in lower 2 feet.
8.0 (204) Limestone, argillaceous, light gray; weathers very light gray; scattered fusulinids.
3.0 (203) Limestone, nodular, medium gray, argillaceous.
6.5 (202) Sandstone, buff; thin limestone lenses; limestone in lower part.
3.0 (201) Limestone, silty, light brownish gray.
2.6 (200) Sandstone, light gray, medium- to fine-grained.
2.9 (199) Limestone, light bluish gray, dense, hard; fusulinids abundant.
5.4 (198) Sandstone, medium buff to light gray.
2.9 (197) Limestone, bluish gray, dense, hard.
14.3 (196) Limestone, highly argillaceous and fossiliferous, light gray; abundant bryozoans and brachiopods; large masses and lenses of black chalcedonized chert; weathers light gray; forms slope.
2.5 (195) Limestone, bluish gray, hard; rough weathered surface.
6.5 (194) Limestone; alternating hard siliceous beds and easily weathered zones; light bluish gray.
2.0 (193) Chert, purplish; upper 1 foot contains large masses limestone.
4.0 (192) Sandstone, buff, fine-grained.
20.0 (191) Limestone, highly nodular; chert common in form of large round nodules; scattered fusulinids; abundant brachiopods; limestone, argillaceous; chert, black to dark gray; upper 1 to 2 feet principally chert.
17.5 (190) Limestone, bluish gray, extremely cherty; chert yellowish to brown.
13.0 (189) Sandstone, gray to buff, fine-grained, cross-bedded, hard.
14.9 (188) Limestone, bluish gray, massive, dense, hard.
3.5 (187) Limestone, medium to light gray, argillaceous; dark chert nodules common; scattered fusulinids.
1.5 (186) Sandstone, light gray to white, fine-grained; irregular contact with limestone below.
3.0 (185) Limestone, bluish gray, dense, hard.
14.0 (184) Sandstone, buff to light gray, fine-grained, cross-bedded; quartzitic in upper 3 feet.
5.0 (183) Limestone, light bluish gray.
22.5 (182) Covered.
3.0 (181) Limestone, bluish gray, hard.
1.0 (180) Quartzite, light gray.
9.8 (179) Slope; seemingly all argillaceous sand.
9.0 (178) Sandstone, gray to light brown, fine-grained; alternating soft and quartzite beds.
2.0 (177) Limestone, bluish gray, hard, massively bedded.
4.8 (176) Sandstone, light gray to buff; breaks into thin slabby sheets.
3.0 (175) Limestone, light bluish gray, hard.
6.0 (174) Sandstone, buff, thin-bedded, laminated; locally stained purple; breaks into slabs.
5.0 (173) Limestone, medium gray, hard.
12.6 (172) Covered; entire slope seemingly nodular lime.
3.0 (171) Limestone, bluish gray, hard, massively bedded; highly sandy in lower part.
9.0 (170) Siltstone, dark brownish red; mainly slope; poorly exposed.
7.0 (169) Limestone, bluish gray, hard; silty in lower part.
1.6 (168) Limestone, bluish gray, highly crinoidal; abundant yellow chert toward top.
0.0 (167) Sandstone, light gray, fine-grained.
21.6 (166) Limestone, earthy; large masses of red chert in middle; light purple at bottom; dark purple toward upper part and highly silty.
3.0 (165) Limestone, light gray, highly crinoidal.
8.0 (164) Limestone, light gray to slightly purplish, highly cherty; large masses and lenses of brown chert; upper 4 feet extremely cherty.
7.0 (163) Sandstone, light gray to buff, fine-grained.
6.3 (162) Limestone, hard, sandy; lenses and masses of yellow chert abundant; upper 3 feet mainly chert; scattered fusulinids.
3.5 (161) Limestone, shaly and nodular in lower 1 foot, fossiliferous, gray, highly crinoidal.
7.0 (160) Sandstone, light gray, fine-grained, hard.
1.0 (159) Limestone, blue gray, highly sandy.
3.5 (158) Sandstone, silty, light gray to pink, fine-grained, sub-quartzitic.
9.6 (157) Sandstone, light gray, fine-grained, cross-bedded; highly mottled purple and yellow.
6.2 (156) Limestone, bluish gray, fossiliferous, soft; upper 1.2 feet hard, purplish.
4.6 (155) Limestone, light gray, silty; 1 foot purple zone 1 foot from base.
5.5 (154) Sandstone, calcareous, highly silty, light gray to bluish gray; alternating with thin white soft sandstone layers.
1.6 (153) Sandstone, soft, fine-grained.
2.5 (152) Sandstone, light gray to white, fine-grained, hard, sub-quartzitic.
4.3 (151) Shale, red, greenish yellow in upper 1 foot.
5.0 (150) Limestone, light purplish gray, nodular; upper 2 feet breaks down easily.
3.0 (149) Shale, bright red to purple; upper 0.5 foot contains nodular green limestone.
1.0 (148) Limestone, nodular, purplish to yellow; interbedded with purple shale.
7.5 (147) Limestone, massive to massively bedded; lenses and beds of red chert.
8.0 (146) Limestone, light purplish gray, contains scattered fusulinids, soft; breaks into slope; middle part shaly with light-gray mottling.
7.0 (145) Partly covered; gray shale showing in middle 3 feet; may have limestone at bottom and top.
4.5 (144) Limestone, medium gray, slightly purplish; massive in lower 2 feet, thinner bedded above.
20.0 (143) Limestone, thin wavy beds; interbedded with yellow to gray shale; stained purplish in upper part.
2.0 (142) Limestone, bluish gray; massive in lower part; thin-bedded above; fusulinids and horn corals common,
1.0 (141) Shale, bright purple.
1.0 (140) Sandstone, highly calcareous, fine-grained, gray.
19.0 (139) Shale, salmon to bright purple; upper 5 to 6 feet poorly exposed.
7.5 (138) Partly covered; apparently all soft highly crinoidal purple limestone.
1.5 (137) Limestone, medium gray; nodular in lower part.
2.4 (136) Shale, red.
1.0 (135) Sandstone, fine-grained, brown to red.
1.0 (134) Shale, greenish gray, thin-bedded.
8.0 (133) Limestone, bluish gray; interbedded with purplish shaly limestone; extremely fossiliferous, fossils mainly in red chert.
14.0 (132) Shale, silty and sandy, gray to purple and red; more silty in upper 3 to 4 feet.
2.8 (131) Limestone, medium gray, silty, evenly bedded; algal.
1.6 (130) Shale, purple, thin-bedded, silty; yellowish gray in upper part.
0.4 (129) Sandstone, greenish gray, highly silty.
1.5 (128) Shale, medium gray, silty, hard and blocky.
2.0 (127) Sandstone, buff, mottled purple, fine-grained, silty.
3.6 (126) Shale, gray, soft.
3.5 (125) Limestone, medium brownish gray, irregular bedding; scattered lenses of red chert; fossiliferous, fossils red and silicified.
1.0 (124) Limestone, medium gray; massive.
2.5 (123) Shale, calcareous; nodular limestone in top; scattered thin beds limestone throughout; abundant fusulinids.
3.6 (122) Limestone, alternating irregular limestone ledges and nodular limestone; upper 1 foot composed almost entirely of fusulinids.
5.7 (121) Shale, light bluish gray.
4.0 (120) Limestone, medium gray, irregularly bedded, hard; contains fusulinids.
6.3 (119) Limestone, highly nodular, medium gray; interbedded with gray shale; forms slope.
2.6 (118) Limestone, medium gray, nodular beds, highly fossiliferous.
8.4 (117) Shale, alternating green and purple in lower 4 feet, bluish gray in middle part; upper part calcareous.
4.0 (116) Limestone, nodular, medium gray; shale break in middle.
4.5 (115) Limestone, nodular, medium gray, silty; nodules 1 to 2 inches in diameter.
3.6 (114) Limestone, medium gray, algal, nodular in appearance; shale break in middle.
14.8 (113) Limestone, nodular, interbedded with silty shale.
2.0 (112) Limestone, nodular; interbedded with shale; abundant fusulinids; upper 1 foot more resistant.
2.3 (111) Shale, thin-bedded; alternating gray and purple.
0.5 (110) Limestone, silty, algal; brownish gray.
5.3 (109) Sandstone; fine-grained; mottled buff and red; middle 1 foot soft.
5.4 (108) Shale, purplish gray, thin-bedded; weathers light lavender; becomes silty in upper part.
2.3 (107) Limestone, light gray; composed mostly of crinoid stems.
3.5 (106) Shale, purplish gray.
1.0 (105) Limestone, medium gray, nodular.
3.4 (104) Shale, salmon colored in lower part, dark purple above.
5.0 (103) Limestone, bluish gray to medium gray, nodular bedded; beds up to 2.5 feet thick; Chaetetes abundant.
5.2 (102) Shale, gray, highly calcareous; abundant limestone nodules.
NOTE: Beds 72-101 duplicated by thrust faulting. Total thickness of Hell's Canyon formation probably greater than measured because of elimination of beds by flowage.
6.8 (71) Limestone, bluish gray, nodular, argillaceous; lower 1.5 feet and upper 2 feet more massively bedded; fusulinids abundant in lower 2 feet; red chert in upper part.
3.8 (70) Shale, greenish yellow in lower 0.5 feet, purplish gray in middle part; upper 1.5 feet contains abundant nodular limestone,
6.5 (69) Limestone, bluish gray, massive, irregular beds, ledge forming; Chaetetes abundant in upper part.
7.1 (68) Limestone, bluish gray, irregularly bedded; upper 4 feet nodular; massive nodular beds; Chaetetes abundant in upper 2 feet.
39.6 (67) Slope; outcrops of nodular limestone and shale throughout interval; shale, purplish in lower part and uppermost part; limestone, bluish gray; argillaceous.
19.2 (66) Limestone, bluish gray; large masses of white to yellow chert throughout; 2.5 feet mainly chert 7.5 feet from top.
13.3 (65) Limestone, bluish gray; lower 4 feet nodular; upper part massively bedded; yellow chert common on upper surface.
6.5 (64) Limestone, brownish gray, massive, scattered small chert masses; weathers to rough surface; upper 1.5 feet forms reentrant on cliff.
7.5 (63) Limestone, bluish gray, brittle, evenly bedded.
1.2 (62) Limestone, light bluish gray, slightly porous.
3.2 (61) Limestone, light bluish gray; weathers yellow.
7.0 (60) Limestone, bluish gray, algal; alternating soft and hard beds; upper 1 foot thin-bedded.
1.8 (59) Limestone, powder blue; weathers yellow; one massive bed.
6.0 (58) Limestone, bluish gray; alternating with gray shale; lower 3 feet mainly lime.
9.0 (57) Limestone, massive; pink in lower 6 feet; yellowish gray in upper part.
0.8 (56) Limestone, pink, thin wavy beds, hard and dense.
5.0 (55) Limestone and shale interbedded; limestone irregular beds, bluish gray; shale brownish gray; upper 2 inches yellowish-green shale.
0.2 (54) Shale, greenish yellow.
4.3 (53) Limestone, bluish gray, massive; abundant calcite geodes.
2.4 (52) Limestone, dove gray; lead-gray 2 inch chert laminae in middle part.
2.5 (51) Shale, greenish yellow; thin limestone near middle part.
4.3 (50) Limestone; as below but more massively bedded.
14.5 (49) Limestone, nodular; upper 1.5 feet soft, bluish gray, weathers brownish; lower 6.5 feet more bluish gray.
7.0 (48) Limestone, light gray, nodular; upper 1 foot weathers brown, algal.
0.4 (47) Limestone, bluish gray, dense, hard.
6.5 (46) Limestone, bluish gray, nodular, highly algal; alternating hard and soft zones.
2.5 (45) Limestone, argillaceous; interbedded with calcareous and fossiliferous shale.
4.0 (44) Limestone, light gray, algal; weathers light bluish.
5.0 (43) Limestone, pink, coarsely crystalline, becoming light gray in upper part.
7.0 (42) Limestone, bluish gray, irregular beds, highly algal; appears conglomeratic.
3.3 (41) Limestone, bluish gray, dense and hard; alternating nodular and irregular beds.
2.0 (40) Limestone, bluish gray, highly nodular.
5.0 (39) Limestone, bluish gray, massively to irregularly bedded, dense and hard.
1.6 (38) Limestone, medium gray, dense, hard.
2.5 (37) Limestone, highly algal; appears conglomeratic with limestone pebbles; weathering easily in upper part.
2.0 (36) Limestone, medium to light gray; one massive bed.
3.2 (35) Limestone, pink, brittle, one massive bed.
2.7 (34) Limestone, medium to light gray, dense, hard.
6.0 (33) Covered.
3.0 (32) Shale, dark red.
0.5 (31) Shale, yellowish green, soft.
2.5 (30) Shale, brown in lower 1 foot, bright red in upper part.
1.0 (29) Shale, greenish yellow; scattered yellowish-gray limestone nodules.
4.5 (28) Shale, red; upper 2 feet contains abundant green limestone nodules.
1.2 (27) Limestone, greenish gray; small pellets of chert common; conglomeratic.
2.0 (26) Shale, red; calcareous shale in middle part.
2.3 (25) Limestone, medium gray, irregularly bedded.
4.6 (24) Sandstone, light gray, fine-grained, hard, cross-bedded; upper part highly calcareous.
0.8 (23) Limestone, argillaceous, light gray.
4.0 (22) Shale, purplish red, hard; contains nodules of claystone in lower 1 foot; upper 0.7 foot more resistant.
3.6 (21) Claystone, silty, local calcareous masses, hard, medium gray to red.
2.4 (20) Shale, red; contains dark-brown limestone nodules.
3.0 (19) Limestone, light bluish gray, slightly yellowish; sand in lower 1 foot; medium gray and nodular in upper part; upper 1 foot contains masses of bedded chert.
4.0 (18) Limestone, medium gray; weathers nodular.
0.8 (17) Limestone, light gray.
1.0 (16) Shale, green, silty, soft.
6.5 (15) Limestone, light medium gray, hard, dense; badly fractured where measured.
12.0 (14) Sandstone, medium- to fine-grained; conglomerate in lower part; coarse-grained in lower 1 foot; contains pebbles of limestone.
2.0 (13) Limestone, medium gray, hard, highly fractured.
3.5 (12) Sandstone, buff, silty, medium- to fine-grained; becoming coarse-grained in upper part.
3.0 (11) Shale, yellow, hard; highly silty in upper part.
2.0 (10) Sandstone, light gray, fine-grained, silty; scattered coarse grains in upper part.
2.5 (9) Shale, highly silty, alternating hard greenish brown and soft green beds, thin-bedded; slightly sandy in top.
7.6 (8) Sandstone, light gray, poorly assorted, coarse- to fine-grained; soft and porous where observed.
3.4 (7) Sandstone, light brown, medium- to fine-grained.
5.5 (6) Sandstone, hard; brownish to yellow in lower 1 foot; upper 1.5 feet hard; middle part breaks down.
3.5 (5) Shale, yellow, silty; becoming more sandy in upper part.
0.8 (4) Sandstone, light gray, medium- to coarse-grained, hard.
3.0 (3) Sandstone, yellowish to greenish, fine-grained, argillaceous, soft.
2.0 (2) Covered; apparently as in bed 3.
89.0 (1) Limestone, hard, fine-grained; glistening on fresh surface; alternating medium to light-gray and dark-gray beds; scattered chert throughout; 3 foot bed of gray sandstone occurs about 15 feet from top. This bed was measured in crest of drag fold and limestone is badly shattered.

Section P-15, Sweetwater Creek, Eagle County, Colorado

Measured on north bluff of Sweetwater Creek, about one quarter of a mile west of mouth of creek. Base of section begins in creek bed and section extends northwestward up valley wall. Section located mainly in sec. 3, T. 4 S., R. 86 W., Eagle County, Colo. (See Fig. 2).

Note: Top of section overlain by 30 feet of cross-bedded conglomeratic, micaceous, red to brown sandstone.
9.0 (38) Limestone, dark gray to black; even thick beds below, thin-bedded at top; highly fossiliferous.
15.0 (37) Shale, dark gray, thin-bedded to fissile; interbedded with nodular limestone; limestone more abundant in upper part, highly fossiliferous; upper 4 feet extremely fossiliferous.
4.0 (36) Limestone, gray, alternating hard and soft beds; contains thin-bedded streaks of micaceous sand.
1.0 (35) Shale, slightly silty, yellowish to bluish gray.
0.8 (34) Limestone, brownish gray, argillaceous.
7.0 (33) Sandstone, gray to greenish-gray, cross-bedded, highly micaceous.
4.8 (32) Shale, dark gray to black; interbedded with nodular dark-gray limestone.
0.4 (31) Sandstone, grayish green, highly micaceous, medium-grained.
12.2 (30) Shale, bluish gray to dark gray; interbedded with abundant nodular limestone; limestone nodules highly algal.
2.5 (29) Sandstone, medium- to coarse-grained, sub-quartzitic, micaceous; alternating soft and hard beds, greenish brown.
11.0 (28) Shale, calcareous, highly fossiliferous, soft, yellowish gray.
5.0 (27) Limestone, argillaceous, dark gray; soft in lower 1.5 feet; becoming shaly in upper 1 foot.
1.0 (26) Conglomerate, fine pebbles of limestone and hard shale; very irregular contact with bed below, probably due to compression.
8.5 (25) Limestone, dark gray to black; interbedded with dark-gray to black gypsiferous shale; fossils abundant 2 to 4 feet from top.
2.0 (24) Limestone, gray, argillaceous, hard, fossiliferous.
4.9 (23) Limestone, dark gray; interbedded with dark-gray to black shale and nodular limestone.
19.5 (22) Shale, dark gray to black; interbedded with even to nodular dark-gray to black limestone.
9.0 (21) Sandstone, medium- to coarse-grained; alternating soft and hard layers, greenish gray, highly micaceous.
5.0 (20) Limestone, gray to dark gray, highly fossiliferous, abundant brachiopods and crinoids; lower 2 feet shaly and soft; middle 2 feet hard; upper 1 foot mainly shale.
4.0 (19) Limestone, argillaceous, black, brittle, evenly bedded.
6.3 (18) Limestone, dark gray to black; interbedded with black fissile shale; limestone alternating silty and argillaceous beds; shale contains abundant gypsum veins.
1.7 (17) Limestone, dark gray, highly fossiliferous, highly argillaceous.
19.0 (16) Limestone, dark gray to black; interbedded with dark-gray to black shale; predominantly shale in middle part, containing numerous veins of selenite.
2.3 (15) Limestone, gray to pearl gray, argillaceous, alternating hard and soft beds, highly fossiliferous.
3.5 (14) Limestone, dark gray to black; interbedded with dark-gray to black thin-bedded shale.
0.5 (13) Conglomerate, as below.
3.5 (12) Limestone and shale, black, brecciated.
1.6 (11) Conglomerate; poorly rounded pebbles and boulders of limestone, sandstone, and shale; highly gypsiferous.
10.0 (10) Limestone, dark gray to black; interbedded with hard black shale.
2.4 (9) Sandstone, gray, argillaceous, fine-grained, silty, porous cones; weathers brown.
2.0 (8) Limestone, gray, argillaceous, fossiliferous; interbedded with thin-bedded gray fossiliferous shale.
14.0 (7) Limestone, dark gray to black, argillaceous; interbedded with dark-gray highly gypsiferous shale; limestone laminated to wavy bedded; thin bed in about middle part; weathers brown.
2.0 (6) Conglomerate; angular fragments of dark-gray to black limestone up to 2 inches diameter imbedded in fine sand.
148.0 (5) Limestone, dark gray to black; interbedded with dark-gray to black fissile shale; lower 5 feet mainly limestone containing abundant bryozoans and small brachiopods; bed of highly algal and fossiliferous limestone 1 foot thick 93 feet above base; limestone porous, brownish gray; slope intermittently exposed at this place.
8.0 (4) Sandstone, gray to dark brown, micaceous, lenticular, medium-grained; overlain by 2.5 feet highly arenaceous and silty gray to yellow shale. Within short distance Bed 5 seems to bevel most of Bed 4.
6.0 (3) Shale, gray to yellow and purple, silty, becoming more sandy toward top, lens of granular conglomerate up to 2 feet thick about 2 feet above base; granules of quartz.
15.0 (2) Limestone and shale; shale, brownish red, hard, abundant hematite shows on surface of lower 7 feet; limestone in upper 6 feet medium to dark gray, interbedded with greenish-gray shale, exposed in road cuts; limestone highly fossiliferous; lower 5 feet red shale with hematite concretions.
40.0 (1) Limestone, massive, gray, hard, highly fossiliferous. Upper surface irregular and cavernous, filled with shale of Bed 2 or of Belden formation.
Note: Bed 2 is missing from the top of the Mississippian limestone only a short distance from this section, probably owing to pre-Belden erosion.

Section P-17, Hell's Canyon, Moffat County, Colorado

Lower part of section measured up west cliff of Hell's Canyon (beds 1-101) on east face of rounded cliff in sec. 31, T. 6 N., R. 102 W., and upper part (beds 102-106) measured on east and west walls of Hell's Canyon in W2 sec. 7, T. 5 N., R. 102 W., Moffat County, Colo. Top of section at head of Hell's Canyon 11.5 miles west junction Wolf Creek and Youghall truck trails and 2 miles by ranch road north of graded county road. (See Figs. 6, 8.)

509.7 (106) Sandstone, buff, fine-grained, highly cross-bedded; weathers buff to light gray, relatively soft where weathered.
Note: Top of Bed 106 obviously not at top of Weber; seemingly 150 to 200 feet of Weber occur above this point. Beds dip at an angle of 63° where last measured, become vertical higher in section. Continuous exposure not observed in upper Weber.
37.0 (105) Dolomite, slightly sandy, porous, light brown, hard; forms prominent brown hogback on north side of canyon.
247.7 (104) Sandstone, dark brown in lower part, buff above, light gray in top, cross-bedded, fine- to medium-grained, glistening; alternating resistant and softer layers; upper part breaks into thin slabby beds.
23.6 (103) Limestone, bluish gray; massively bedded at top and bottom, brittle in middle part; abundant yellow chert masses in upper massive part, fossiliferous.
53.5 (102) Sandstone, buff, highly cross-bedded, fine- to medium-grained.
8.0 (101) Limestone, light gray, dense and hard; contains abundant fusulinids; forms cap on top of hill in section 31.
45.0 (100) Sandstone, brown, cross-bedded, fine-grained; upper 5 feet light gray.
5.0 (99) Limestone, sandy, light gray, breaks into thin sheets, cross-bedded.
22.0 (98) Limestone, light gray, crystalline, highly fossiliferous; lenses of chert abundant 10 feet from base; contains fusulinids.
20.0 (97) Sandstone; buff, medium- to fine-grained; cross-bedded.
6.0 (96) Limestone, gray. to bluish gray, highly crinoidal; fusulinids common.
54.0 (95) Sandstone, brown, cross-bedded, fine-grained.
7.0 (94) Limestone, light gray, highly fossiliferous; abundant fusulinids; grading upward to a 1 foot bed of purple calcareous sand; abundant thin dark-gray chert layers.
95.0 (93) Sandstone, brown, fine-grained, highly cross-bedded.
7.5 (92) Limestone, light gray, highly crinoidal (composed largely of crinoid stems).
65.0 (91) Sandstone, brownish red, fine- to medium-grained, cross-bedded to massively bedded.
5.8 (90) Limestone, gray, hard, slightly sandy, finely oolitic; teeming with fusulinids in upper part.
3.6 (89) Sandstone, light gray, fine-grained, calcareous, cross-bedded; cliff faces covered with chert.
3.5 (88) Limestone, gray to purplish gray, sandy, broadly cross-bedded; weathers bluish gray.
4.0 (87) Limestone, light gray, highly fossiliferous, fusulinids.
4.3 (86) Sandstone, light pink, fine-grained, one massive bed, hard.
3.8 (85) Sandstone, reddish brown, fine-grained, cross-bedded.
6.5 (84) Limestone, light gray, stained purple, fossiliferous; upper 3.5 feet sandy, slightly fossiliferous.
95.0 (83) Sandstone, light red, cross-bedded, fine-grained.
7.0 (82) Sandstone, light gray, fine-grained, hard, dense; forms one continuous massive ledge.
5.0 (81) Sandstone, reddish brown, fine-grained, mottled with gray; bright red and soft in lower 1.5 feet.
1.4 (80) Sandstone, bluish gray to brown, highly calcareous, nodular in appearance.
1.3 (79) Sandstone, light purplish brown, hard, calcareous; mottled with gray spherical masses.
4.5 (78) Sandstone, reddish brown, cross-bedded, laminated with gray; abundant concentric red and gray rings in upper part.
1.5 (77) Sandstone, fine-grained, thin-bedded, alternating reddish brown and gray streaks; breaks into thin streaks.
6.0 (76) Sandstone, bright red, highly silty, fine-grained; upper 1 foot highly mottled with gray.
11.0 (75) Limestone, bluish gray, highly crinoidal; alternating thick and thin beds; weathers to rough surface.
15.0 (74) Sandstone, brownish red, fine-grained, cross-bedded.
10.5 (73) Limestone, gray, dense, hard; lenses and masses of red chert 3.5 feet above base; highly crinoidal at top.
6.5 (72) Sandstone, gray, fine-grained, soft.
1.0 (71) Siltstone, gray; interbedded with thin layers of red and gray siltstone.
2.2 (70) Sandstone, red, fine-grained, silty, laminated.
5.0 (69) Siltstone, brownish red, thin- to nodular-bedded; contains abundant light-gray concretionary mottling.
8.0 (68) Limestone, gray to slightly purplish; has abundant spherical light-gray mottling; more mottled in upper part; upper part mainly shale.
3.0 (67) Limestone, gray; weathers light bluish gray; disseminated chert.
8.0 (66) Shale, bluish gray, thin-bedded, fissile.
2.0 (65) Limestone, gray, hard, teeming with fossils.
4.5 (64) Shale, red in lower 2.5 feet, bluish gray in upper part.
2.0 (63) Sandstone, gray, weathers brown, highly cross-bedded, fine-grained, hard.
0.5 (62) Shale, yellow, soft.
3.5 (61) Limestone, gray, argillaceous, teeming with fossils; interbedded with thin fissile shale.
1.0 (60) Shale, gray, highly calcareous, highly fossiliferous; mottled with small spherical concretionary structures.
3.3 (59) Limestone, gray; composed largely of fossils; two hard beds.
2.0 (58) Shale, purplish gray, thin-bedded, silty.
2.0 (57) Limestone, gray, highly fossiliferous; abundant thin lenses of chert.
13.0 (56) Shale, gray; composed largely of fossils in lower part, especially bryozoans, horn corals, and crinoids.
2.5 (55) Limestone, gray, coquinoid, partly silicified; red stringers of chert.
10.0 (54) Sandstone, purple, thin-bedded, fine-grained; alternating buff and purple layers.
1.8 (53) Limestone, gray to bluish gray, wavily bedded, highly fossiliferous.
8.5 (52) Sandstone, light gray to buff, medium- to fine-grained, cross-bedded; weathers to spalling surface.
10.0 (51) Shale, gray, slightly bluish; nodular limestone abundant in lower 5 feet; upper 3 to 4 feet not exposed.
1.5 (50) Sandstone, purple, highly calcareous, fine-grained, wavily bedded.
1.8 (49) Limestone, gray, dense, hard.
1.0 (48) Shale, gray to brownish gray; brown and sandy in lower part.
1.0 (47) Sandstone, dark reddish brown, fine-grained.
2.0 (46) Shale, alternating greenish gray, purple, and light gray.
2.0 (45) Limestone, gray, dense and hard; yellow chert in top; silicified fossils in upper part.
1.5 (44) Limestone, bluish gray, dense and hard; upper 0.6 foot weathers easily.
0.3 (43) Shale, purple, sandy.
4.0 (42) Sandstone, light gray, fine-grained, hard; upper 2 feet soft; upper part contains masses of calcareous sandstone.
0.5 (41) Shale, bluish gray to gray.
3.0 (40) Limestone, bluish gray, hard, highly fossiliferous; most fossils silicified (red chert); abundant masses of red chert; algal in upper part.
2.5 (39) Shale, gray, highly calcareous and thin beds of limestone; highly fossiliferous; brachiopods abundant.
2.3 (38) Limestone, greenish gray to gray; red chert masses abundant; highly fossiliferous; crinoidal; abundant fusulinids, granular appearance.
15.0 (37) Limestone, highly silty, nodular; interbedded with silty shale; gray to bluish gray, purplish tinge; streaks of purple shale 10 feet above base; abundant red chert lenses and nodules in upper 4 feet.
5.5 (36) Limestone, gray to purplish gray, wavily bedded to laminated, silty, hard.
6.0 (35) Limestone, thin-bedded, highly argillaceous in lower 2 to 3 feet, gray to purplish gray, mottled gray and purple; interbedded with thin shales toward top.
2.8 (34) Limestone, gray to bluish gray, dense and hard; teeming with fusulinids in upper 1.3 feet.
0.6 (33) Shale, light greenish gray, thin-bedded, highly calcareous; with thin nodules of limestone.
3.0 (32) Sandstone, purplish gray, fine-grained, thin-bedded; weathers yellowish, becomes dark purple and argillaceous in upper part.
4.0 (31) Shale, bluish to greenish gray, hard; gradational with bed above.
8.5 (30) Limestone, light bluish gray, dense, hard; upper 3 to 4 feet almost entirely light gray to blue chert.
3.5 (29) Limestone, light gray, earthy, brittle.
1.5 (28) Shale, bluish gray, highly silty; interbedded with thin limestones in upper part.
3.0 (27) Covered.
3.0 (26) Limestone, light bluish gray, dense and hard; large dentritic to spherical masses of gray chert; abundant fusulinids.
1.0 (25) Shale, thin-bedded to fissile; highly calcareous and fossiliferous, abundant fusulinids.
1.3 (24) Limestone, light bluish gray, dense and hard; contains abundant colonies of Chaetetes and scattered fusulinids.
2.0 (23) Shale, gray, sandy.
40.0 (22) Shale, red to purple; contains scattered zones of nodular limestone in lower part; upper 5 to 6 feet dark brown; sandy and silty.
2.0 (21) Siltstone, highly argillaceous, purplish red, highly mottled with spherical light gray masses, calcareous; red chert in lower part.
21.0 (20) Shale, purplish gray; contains nodules and thin beds of purplish-gray to yellow limestone; becoming harder in upper 3 to 4 feet; highly mottled with spherical gray concretionary spots; highly silty in upper part; highly fossiliferous calcareous zone 5 feet from base.
5.0 (19) Shale, red to dark brown.
1.0 (18) Limestone or sandstone, light gray, hard, purple mottling; thin stringers of bright-red chert in middle part.
3.0 (17) Siltstone to fine sandstone, purple to red; highly stained with light-gray concretionary mottling.
2.2 (16) Sandstone, light gray to white, fine-grained; in two hard beds; upper bed highly stained with purple mottling.
1.5 (15) Siltstone, purplish gray, alternating hard and soft beds, laminated on weathered edges; abundant light-gray concretionary areas.
1.5 (14) Siltstone, purplish gray, highly calcareous, hard; abundant lightgray concretionary areas.
11.0 (13) Shale, purple to purplish gray, thin-bedded to fissile; slightly nodular in upper part; abundant spherical concretionary light-gray mottling.
2.5 (12) Limestone, gray to slightly brownish gray, dense, hard; upper part greenish gray; in two massive beds.
6.5 (11) Shale, purplish gray; nodules of limestone common; abundant light-gray concretionary mottling.
3.0 (10) Limestone, bluish gray to greenish gray, nodular; stringers and masses of red chert abundant.
4.5 (9) Limestone and shale; shale purplish gray, limestone purplish gray and nodular; abundant concretionary spots.
15.0 (8) Shale, purplish gray, gray to purplish-gray limestone nodules abundant 3 to 7 feet below top.
5.0 (7) Limestone, light purplish gray, highly argillaceous; soft crinkly beds; small masses of red chert common.
10.0 (6) Conglomerate, limestone and chert pebbles up to 2 inches in diameter; interstices filled with yellow to red sandstone.
10.5 (5) Limestone, light bluish gray; massive in lower part; nodular and jointed in upper part; upper 2 to 3 feet composed largely of light-gray to white chert.
3.5 (4) Limestone, bluish gray, wavily bedded, laminated; 1 foot bed of purple to brown shale at base; middle part cherty; gray shale and nodular limestone at top.
2.0 (3) Limestone, bluish gray, dense, hard; algal at top.
2.3 (2) Limestone, gray, highly argillaceous; interbedded with calcareous shale; highly fossiliferous.
108.0 (1) Limestone, gray to bluish gray; alternating massive to nodular beds interbedded with thin purple shales and nodular limestone zones; yellow to light-gray beds and masses of chert abundant throughout; gray to purple chert becomes more abundant in upper 30 feet; uppermost bed contains lenses up to 1.5 feet thick of gray to purple chert; algae abundant in upper part of major limestone beds; highly fossiliferous.

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Kansas Geological Survey, Geology
Placed on web Sept. 10, 2017; originally published Oct. 15, 1945.
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