General Setting
Information Search and Selection

Com ments

on

Geo logic

Para meters

1 Depth:

2 Permeability/Hydraulic Conductivity:

3 Formation Thickness:
4 Net Sand Thickness:
5 Percent Shale:
6 Continuity:
7 Top Seal Thickness:
8 Continuity of top seal:
9 Hydrocarbon Production:
10 Fluid Residence Time:
11 Flow Direction Elevation:

12

CO2 Solu bility Brine

 12a Temperature:
12b Pressure:
12c Salinity:
13 Rock/Water Reaction:
14 Porosity:
15 Water Chemistry:
16 Rock Mineralogy:

Fox Hills — Lower Hell Creek, Powder River Basin

Comments on Geologic Parameters

1 Depth::

The principal source for mapping formation depth of the Fox Hills Sandstone in the Powder River Basin is Lewis and Hotchkiss (1981), who presented a structure map on the top of the Fox Hills Sandstone; it reaches a maximum depth of more than 3,000 ft (>910 m) in the steeply dipping, western part of the basin, west of Gillette. We subtracted the subsea elevation of the formation top from the gridded land-surface elevation from a DEM generated from Digital Terrain Elevation Data (National Imagery and Mapping Agency, 2000) to calculate depth to top Fox Hills.

1 Map:

1 Reference:

Fox, J., and Higley, D., 1987, Structural at the Base of the Upper Cretaceous Fox Hills Sandstone, Power River Basin, Wyoming and Montana. USGS OFR 8

Lewis, B. D., and Hotchkiss, W. R., 1981, Thickness, percent sand, and configuration of shallow hydrogeologic units in the Powder River Basin, Montana and Wyoming: U. S. Geological Survey, Miscellaneous Investigations Series, Map I-1317, 6 sheets.

National Imagery and Mapping Agency, 2000, Digital terrain elevation data (DTED Level 0), http:/www.gisdatadept.com.