CONTENTS. 9 
Descriptive geology — Continued. 
Mountains southeast of Pahute Mesa — Continued. 
Shoshone and Skull mountains and the hills in the vicinity — Con. 
General geology — Continued. 
Igneous rocks — Continued. 
Later rhyolite 145 
Basalt 14<; 
Structure i 17 
Economic geology 
Specter Range and Skeleton Hills is: 
Topography and geography 147 
General geology 148 
Sedimentary rocks 14S 
Prospect Mountain quartzite 1 is 
Prospect Mountain limestone 148 
Igneous rocks 140 
Structure 140 
Economic geology 150 
Yucca Mountain 150 
Topography and geography 150 
General geology 150 
Post- Jurassic pegmatite 15] 
Rhyolite and latite 151 
Basalt 151 
Structure l 152 
Economic geology 152 
Timber Mountain 153 
Topography and geography 153 
Geology 153 
Rhyolite 15:; 
Basalt 15:; 
Bare Mountain 153 
Topography and geography 153 
General geology 154 
Paleozoic sedimentary rocks 1"»1 
Igneous rocks 155 
Post-Jurassic pegmatites 155 
Diorite porphyry 150 
Tertiary rhyolite and basalt 150 
Structure 150 
Economic geology . 150 
Sarcobatus Flat 157 
Amargosa Desert 1>,s 
Amargosa mountain system ,,;n 
Amargosa Range 1 160 
Topography and geography 160 
General geology " ; - 
Sedimentary rocks 
Prospect Mountain quartzite (?) 
Pogonip limestone 
Eureka quartzite 1<; -' 
Lone Mountain limestone 
Siebert lake beds and contemporaneous deposits. _ 
Older alluvium 
