196 R. W. Buddemeier et a\.
CRETACEOUS BEDROCK
D
UndlIIe CreIac80uS rocks
(Dalcola Formation)
PERMIAN BEDROCK
Undifle Permian roc:ks
<:.dar Hills
Samslone
Harper
Sail Plain
Formation
Fig. 2. Detail of aquifer and bedrock geology for the region around the GMD5
label in Figure I. The darker-colored formations at depth and to the east are saltbearing, and produce strong brine discharges near the boundary of the Cretaceous
formation and along Rattlesnake Creek.