Lake Manly: An Extinct Lake of Death Valley

N the desert part of southeastern California and southern Nevada there are long parallel mountain ranges separated by troughs popularly called valleys, although they are unlike the ordinary valleys of humid regions and are probably of different origin. The deepest and one of the longest of these is Death Valley-once a place of mystery and gruesome tales but now fast becoming a winter resort for the motoring tourist. Such human beings as may have roamed over the desert part of California and Nevada in late Pleistocene time could have looked down from the mountains that flank the great trough of Death Valley and have seen a beautiful blue lake about thrice as long as the present Pyramid Lake, Nevada, although not as wide. This now extinct lake has been appropriately named' in honor of W. L. Manly, who led and heroically rescued the first party of white emigrants who entered Death Valley in I849. Lake Manly was probably one of the temporary lakes that developed in the undrained basins of the desert region during a cooler and moister period. Today only a few of them remain-Great Salt Lake, Walker Lake, Mono Lake, Pyramid Lake, and others-but in that earlier time there were many more, and those that still exist were much larger.2 In fact nearly all the arid basins, of which there are several hundred in the Southwestern states, then contained lakes. So obscure is the evidence of the former existence of Lake Manly that most of the earlier geologists who visited Death Valley were skeptical about it. In I9253 Noble reported that he and Gregory had observed several lake-shore terraces upon a basalt hill near the south end of Death Valley. Here and there to the north other obscure terraces were revealed. The record of the lake is to be found chiefly in its deposits and in the wave-carved terraces.