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Show i 0 I Ancestry of i Great Salt Lake Although its placid waters belie the fact that it was ever anything but an inland salt-water sea, Great Salt Lake was anciently a fresh water body with an outlet to the I Pacific Ocean. This was told to I avants from all over America by Prof essor Hyrum Schneider of the department of geology, University i of Utah, who delivered a lecture on the ancestry of Great Salt Lake as a feature of the convention sessions of the American Association Associa-tion for the Advancement of Science, Pacific division, held on :the university campus recently. Three hundred forty-six miles long, and 145 miles wide, with a depth of 1,000 feet, Lake Bonneville Bonne-ville had an area of about 20,000 square miles about the size of Lake Huron, and ten times as large as the area of Great Salt Lake. The lake was named after Captain Benjamin Bonneville by Grove K. Gilbert, first Geologist completely to chart the outline of the ancient inland sea. The lake stood at this level, Dr. Schneider said, long enough to cut a shore tsrrace 210 feet wide in quartzite, a very hard mctamorphic rock. Then with Increased moisture mois-ture in the area the lake rose from this level, known as the "Bonneville" "Bonne-ville" level, and developed an outlet out-let at Red Rock pass at the north j end of Cache Valley. For a com-1 paratively long tim3 the lake dis-l charged a large volume of water to the Pacific Ocean by way of the Snake and Columbia rivers. This copious discharge of water continued contin-ued until the channel and lake had been lowered 375 feet. Then the actual phenomenon of salinification occurred. The rain- j fall and other moisture conditions, j because of changes for a drier cli-, mate, were no longer able to main- j tain the lake at this discharge level, i and it dwindled to its present, size by dessicatlon. Although the climate was colder; than now, with attendant glaciers ; in the Wasatch and Uintah Mountains, Moun-tains, such animals as the musk ox, mountain sheep, horse, camel, and mammoth lived along its shores, according to Dr. Schneider. o |