Description: <DIV STYLE="text-align:Left;"><P STYLE="font-size:16ptmargin:7 0 7 0;"><SPAN>Lewis and Hotchkiss (1981) 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.</SPAN></P><DIV><P><SPAN /></P></DIV></DIV>
Copyright Text: 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.