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Show 404 APPENDIX JJ.- GKOLOOY. sandstones, • which may he of. the Age of the coal, or beneath that formation.* ' » * . From July 80th to August 2d, the noted of the Journal andxthe specimens show the existence of compact quarts rook, crystallised silicious limestone, and conglomerate. From August 3d to August 6th, I have no specimens indicating the character of the formations passed over. JEVom 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 Jfam& Hm* 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 Pannaek and the head of the Malade. South of Fort Hall the specimens. collected are of granular sandstone, « nd of quarts rock resulting from an altered sandstone; to the west, and above these, are chert and* limestone of earhonw . ferous age. The limestone in this locality contains fewer vhelfa 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 folcose and mica slates, hornblende rocka, 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 Fro* monitory Point, and Mad Island, on the east side of the lake, ' judging fronvthe numerous specimens, consist principally'of talcose and mica slates, with hornblende tock. £!& rrington Island, Hat Island, a point north by west from Hat Island, naxne not knows, sod a part of Strong's Knob,* consist of similar rocks with some of altered sandstone or quartz rock. In several localities, aft 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 fell the fact* in my possession, it would appear that these* < metamorphic rocks are distinctly stratified and highly inclined, but do < noi. attain any great elevation. - The direction of the ranges, • |