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Show • 4 0 4 APPENDIX E.- GEOLOGY. Bandston^ Mhich 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 specimensjfcro the existence of compact quartz rock, crystallized silicious l^ ptone, 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 NautUu* and other marine shells. From this time nearly all the reconis 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 tl^ g 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 carboniferous 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 Gysat 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 Promontory 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 quaA 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 sandstone, which is partially altered, and assumes the character of a quartz rock. From all the facts in my possession, it would apjjlar that these metamorphic rocks are distinctly stratified and highly inclined, but do not attain any great elevation. The direction of the ranges, |