855 



JUATERNAUV .. j ^Ippor Qgaternary . 

 ( Lower Qnatornary . 



I Gravels and loose detrital material. 



Fine muds and silts. 



■ Wyomin J C o n- 

 KlomoiMte. 



J Coar.se structureless cinglomerate. 



Pliocouo . V 



Jfi.'ibrara . . [Coarse and fine friable sauJstouos, and siliceous limestones 

 { horizontal whore obssrveil. 



HumV))ldt 



f Generally siliceous fino-srained, friable bids; frcquontly vol- 

 i canic tufas; undisturbed. 



North Park 



-1 



Drab sindstones and limestones, liosely asglomeratod ; undis- 

 turbed. 



Teetiauy s Miocene 



Truckeo . 



White River. 



f Fo3siliferO!i8 limestones, gravels, and volcanic (palagonite) tufas ; 

 [ ■ upturned. 



Fine light-colored sandstones, with clays inter-itratified. 



Uiuta;, 



', Coarse and fine pinkish sandstones, gravel conglomerates, and 

 ! argillaceous beds. 



Eocene 



.:i 



Bridger . 



I Drab thin-bdded sandstones, and treen marls, rich in verte- 

 I brato remriiiis ; slight development of limestones. 



Green Kiver . 



; Thin oalcareoni .shiles, wilh fishes and insects; buff calcareous 

 ; sandstones, and lignite toward tho base. 



Vermlllio'i Creek 



C Coar-s ^ pink aid cUocolatn-colored sandstones, with large de- 



l velon^iie it of conglomerates. Ooryphodon beds. 



C Coarse wbito an<l le Jdisli sandstones, heavily bedded, with large 



-Laramie < dcvolopaient rf conl seams. Fossils marine and brackish 



( water. TJacoufoimablo with foregoing aeries. 



Cretaceous ...i 



.Fox Hill . 



; Coarse white s imlstouos, heavily bedded ; few coal seams ; less 

 I iron than former ; to jsils marine. 



. Colorado - 



5 M St y blue mid ycli w c.a.s and marl:', wiiU tliiu sands ones. 

 ) Co.ll. Fosiilile'rom. 



I D.ikot I . 



I Sandstones and characteiisic conglomo^atc. 



JURASSIC- 



fEastof Wahsatch. Clays and limestones; fossiliferous ; small 

 J devolopmoat. 

 ■ ^ In Nevada. Ileavy limestones, shales, and argillites ; greater 

 I development. 



TRIAS'ilC . 



Red Beds-; 



Star Peak. 



Koipato . 



f Heavy - bedded, fossilif- 

 erous blue limestones, 

 I interstratified with 

 . i quartzitic schists and 

 I slates. 



I 



5 Quartzites, argillites, and 

 ■ \ porphyroids. 



The Red Beds, which represent the en- 

 tire development of Triassic rocks 

 eastof the Wahsatch, consistmainly 

 of coarso, heavily-bedded sandstones, 

 of prevailing red color, sometimes 

 white or buff, with some clay,s, thin 

 limestone beds, and frequent depos- 

 its of gypsum. Almost barren of 

 fossils. 



'Permo-C irboniforous | Clays and argillaceous limestones, with ripple-marks. 



Upper Coal Measures. 



■ lu general, lisht-colored bine and drab limestones, more or Ic^s 

 siliceons, and passing in places into sandstones; generally 

 ' fossiliferous. 



Carbonifekous < 



■yVeber Quartzite 



: Compact s ^ndstones and quartzites, fiequently of reddish colors, 

 : with local developments of intorstr.itifie'd calcareous and 

 ' argillaceous beds and conglomerates ; nonfossiliferous. 



Lower Coal Measures . 



t. Sub-Carboniferous 



f Nevada Devonian 



■ 1 [■ Heavy-bedded blue and gray limestones, with some 



'["Wahsatch J IntcrstratiQed quartzites, more fiequently in tho 

 '_ j limestone. 1 upper part of the series. Lower beds siliceous 

 ) (at times. Fossiliferous. 



Devonian 



j Ogden Quartzite. 



White saccharoidal quartzite, pink tints; conglomerate wiih 

 flattened pebbles. 



Silurian TJte-Pogonip limestone. 



Cambrian 



fPogonip 



. I Compact blue limestone, with included argillites, passing into 

 1 )■ calcareous shalei. More largely developed in Nevada, where 

 j tho limestone carries primordial fossils at the base. 



( Generally white quartzites, more or less iron-stained, with 

 . < aomo (ioveloijment of micaceous beds, and heavy dark-blue 

 I argillites. 



Huronian . 



: Plagioclase- hornblende granites, diorite-gneisses, 

 limestones, and quartzites. 



argillites. 



Lauuestias . 



; Coarse red orthoclase-mica granites, mica-gneisses, and schists. 

 ; wilh deposits of ilmenite and graphite. 



