[Illustration: _Local residents were divided over the park issue. Two local park proponents, Mardy and the late Olaus J. Murie, are shown at a 1949 annual council meeting of the Wilderness Society. The Muries advocated park enlargement._] Geologic forces have not always been subtle influences in the valley. Melting snow and heavy rains in June 1925 saturated a layer of clay sandwiched between sedimentary rock layers that form the north end of Sheep Mountain, near Kelly. An earthquake, probably, triggered an enormous landslide, and thousands of tons of debris raced down into the river, damming it and backing up a lake 5 miles long and 200 feet deep. Two years later the top 50 feet of the dam broke off and a wall of water rushed down through Kelly, leveling all buildings except the church and school. Six lives were lost, despite ample warning. The landslide scar on Sheep Mountain’s north end is more than 5,000 feet long and 2,500 feet wide. Geologists say that more of Sheep Mountain is perched to slide, given similar spring rainfall and an earthquake trigger. The rise of the Teton Range and the corresponding sinking of Jackson Hole continues, although not at an even rate. The action continues by irregular crustal movements known as earthquakes. Geologist John D. Love, longtime interpreter of the dynamics of the Teton Range, feels that a major earthquake movement along the Teton fault, of as much as 20 feet, could happen at any time. The impact would be many more times severe than the landslide and ensuing flood at Kelly. But such things are not given to easy and precise prediction. The Elk Herd [Illustration: Elk with antlers.] [Illustration: Elk herd.]