404 APPENDIX E. — GEOLOGY. 



sandstones, which may be of the age of the coal, or. beneath that 

 formation. 



From July 30th to August 2d, the notes of the Journal and the 

 specimens show the existence of compact quartz rock, crystallized 

 silicious limestone, and conglomerate. 



From August 3d to August 6th, I have no specimens indicating 

 the character of the formations passed over. From this date to 

 August 11th, including the distance from the southern extremity 

 of the Wind River Mountains to Fort Bridger, the collections are 

 all of marine tertiary age, including many specimens of JVautilus 

 and other marine shells. 



From this time nearly all the records and collections pertain to 

 the Salt Lake and its vicinity. Near Fort Hall several specimens 

 of volcanic rocks were collected, and obsidian and lava about 

 the Pannack and the head of the Malade. 



South of Fort Hall the specimens collected are of granular 

 sandstone, and of quartz rock resulting from an altered sandstone; 

 to the west, and above these, are chert and limestone of carboni- 

 ferous age. The limestone in this locality contains fewer shells 

 than that in the more easterly localities, but has a large number 

 of corals. 



The specimens collected in the islands and shores of the Great 

 Salt Lake are sufficient to give one a very good idea of the general 

 geological features. The specimens are of metamorphic rocks, 

 consisting of talcose and mica slates, hornblende rocks, and a 

 few specimens of granitic or sienitic character. 



Some specimens of the latter description occur along the valley 

 of Ogden's River. Antelope Island, Fremont Island, a part of Pro- 

 montory Point, and Mud Island, on the east side of the lake, 

 judging from the numerous specimens, consist principally of talcose 

 and mica slates, with hornblende rock. Carrington Island, Hat 

 Island, a point north by west from Hat Island, name not known, 

 and a part of Strong's Knob, consist of similar rocks with some 

 of ,altered sandstone or quartz rock. In several localities, as at 

 Promontory Point and near Mud Island, the metamorphic strata 

 appear to be overlaid by a coarse conglomerate, or coarse sand- 

 stone, which is partially altered, and assumes the character of a 

 quartz rock. 



From all the facts in my possession, it would appear that these 

 metamorphic rocks are distinctly stratified and highly inclined, but 

 do not attain any great elevation. The direction of the ranges, 



