GEOLOGICAL SURVEY

CARBONIFEROUS

TERTIARY

CRETACEOUS

JURASSIC

TRIASSIC

ORDOVICIAN

a

CAMBRIAN

PERMIAN}

Oligocene

Eocene

Paleocene

Upper Cretaceous

Y
Lower Cretaceous

on a

Cody shale

BULLETIN 1027 PLATE8

Formation Section Thickness Character of rocks
=
0-300! Igneous pebble and cobble conglomerate with a marlstone matrix interbedded
White River formation with light-gray marls and light-brown tuffaceous claystones

Interbedded granule and coarse-grained sandstone, greenish-gray shale, and
Moncrief drab siltstone grading upward into coarse boulder beds containing blocks of

raTEATSCTP igneous rocks derived from the pre-Cambrian core of the Bighorn Moun-
. 500! tains. Grades eastward into the finer grained facies of the Wasatch forma-

Wasatch formation | x ingsbury na rion
conglomerate 1800!
member

Fort Union formation

Dominantly conglomerate; pebbles and cobbles derived from Paleozoic units;
grades eastward into the lower part of the Wasatch formation. Both the

Moncrief and Kingsbury conglomerate members thin eastward

3450!

Interbedded siltstone, gray shale, and soft argillaceous sandstones. In the
area south of Crazy Woman Creek the unit contains several coal beds, but
these grade northward into carbonaceous shales. The upper 600 feet in the
vicinity of Billy triangulation station contains many lenses of quartzite peb-
bles and limestone pebble conglomerate

Flathead sandstone

Satsocied'ecy|

1950' | Interbedded light- to yellowish-gray soft sandstones and dark-gray shales;
Lance formation to the lower 600 feet contains several lenticular beds of yellowish-gray re-
2200! sistant sandstone
Bearpaw shale 200' Dark-greenish-gray shale with siltstone laminae
Fine- to medium-grained yellowish-gray sandstone with large brown ellips-
Genin Eoaa tens oidal concretions in the lower half
Dark-gray shale with some siltstone and sandstone beds and laminae; the
3670! Shannon sandstone member occurs 925 feet below the top; shale of the
lower 1, 400 feet is calcareous in places
phennon|sandetoneimenbey 480! Interlaminated gray siltstone, sandstone, and dark-gray shale; contains a
resistant conglomeratic sandstone ledge at top
1 Upper 350 feet is dominantly gray laminated siliceous shale; the lower 150
500 feet is dark-gray nonsiliceous shale
40! Light-gray medium-grained sandstone containing black and red grains
165! Dark-gray clay shale with some interlaminated siltstone in the lower 80 feet
156! Sandstone at base overlain by interlaminated siltstone and dark-gray shale
185! | Thin sandstone and siltstone beds and varicolored claystone
285! Calcareous sandstone in the lower half and silt shale in the upper half
Frontier formation 15!
Mowry shale to Red claystone and siltstone, gypsum, and thin argillaceous limestones
120!
Newcastle sandstone
Skull Creek shale 750' | Red siltstone, silty sandstone, red shale; contains the Alcova limestone
to member; unit weathers to slopes
Cloverly formation 870!
Morrison formation
250! | Red shale, gypsum, and thin beds of dolomitic limestone
Sundance formation
Gypsum Spring formation
~ 50! Sandstone, fine- to medium-grained, crossbedded, resistant, yellowish-gray
Chugwater formation 350 to salmon-pink; contains thin dolomite beds in the lower part
Red shale and
gypsum sequence 250" Red sandstone and claystone and tan massive dolomite
Tensl een : ‘Thin-bedded to massive resistant limy dolomite and limestone; unit forms
ensleep sant © 550 prominant cliffs
Amsden formation 150"
Ez = t Basal light-gray to red sandstone overlain by resistant massive pitted gray
Madison limestone = ° dolomite
350!
Bighorn dolomite | | Interbedded grayish-green shales, gray siltstone, light-gray limestone, and
550 flat-pebble conglomerate; unit is capped by a 50-foot red limestone
Gallatin limestone and
Gros Ventre formation, undivided
260! Tan to light-brown quartz sandstone; contains quartz pebble conglomerate in

basal portion

GENERALIZED SECTION OF SEDIMENTARY UNITS EXPOSED IN THE
CRAZY WOMAN CREEK AREA, JOHNSON COUNTY, WYOMING

339462 O ~ 55 (In pocket) No.2