EKDLicn.] SWEETWATER DISTRICT TABLE OF FORMATIONS. 



155 



Table enumerating the various formations and groups, ^c. — Continued. 



5<1 



Fossils. 



Numerous Leaves. Inverte- 

 brates of fresh-water and 

 brackish-water tnies. Os- 

 trca, Viviparus, JJnio, Ooni- 

 obasis, &c. 



Character of strata. 



Series of shales and sandstones. Coal near 

 the top and near baao. Clays and shales 

 iu viciuitv of coal. Thinning out north- 

 ■ward, and incomplete there. 



Inoceramus, Ostrea, and nu- 

 merous other Invertebrates. 



Sandstones and shales near the top, con- 

 taining coal. Massive arenaceous and 

 micaceous shales lower down. Shales 

 and sandstones at base. Thinner north- 

 ward. 



500 

 to 

 1300 





Inocerarmis, Ostrea, and other 

 Invertebrates. 



Leaves, Gryphcea, Inoceramus, 

 and other fossils. 



Sandstones at top. Massive dark - (jray 

 shales, weathering light gray and white. 

 Carbonaceous shales. Thinner toward 

 north. 



Massive yellow and white sandstones, with 

 carbonaceous shales. Gray, yellow, and 

 brown shales. Sandstones' and conglom- 

 erates near base. Thinner northward. 



Belemmtes, Gryphcea, Pecten, 

 and other Invertebrates. 



Natica in dolomitic limestones. 

 Fucoid forms in sandstones. 



Indistinct remains of Plants. 



"White, yellow, pint, and light-green marls 

 at top. Yellow shales, with limestones, 

 lower down. Massive blue limestones 

 near base. Thicker north. 



TVliite, yellow, and pink coarse-grained 

 sandstones. Thin beds of shales be- 

 tween them. 



Massive red argQlaceous sandstones. Eed 

 shales, with dolomitic limestones, ia the 

 middle. Eed and pink sandstones, with 

 gypsum, near base. Thicker northward. 



Pink and yellow sandstones, with yellow 

 and greenish shales. Hippie-marks. 



600 

 to 

 850 



600 

 to 

 700 



120 

 to 

 220 



150 

 to 

 400 



600 

 to 

 800 



150 

 to 

 320 



Prodvxitus, Orthoceras, Orthis, 

 and other fossils, all silici- 

 fied in the northern portions 

 of the district. 



Massive blue limestone, containing large 

 quantities of concretionary silica. To- 

 ward the base some magncsian lime- 

 stones. Thicker toward the north. 



1400 



to 



2200 



Crinnids, Corals, Chonetes, 

 Spirifer, Orthis, Orthoceras, 

 Productus, and others, most- 

 ly sUiciiied. 



Dolomitic limestones, yellow and gray dol- 

 omites, witli some sandstones near top. 

 Thicker northward. 



350 

 to 

 700 



