Section 4, Southeastern Idaho

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Chapter 9 -Bear Lake Valley
Chapter 10 -Soda Springs Area
Chapter 11 -Caribou Mountain Area
Chapter 12 -Gem Valley & Chesterfield
Chapter 13 -Lava Hot Springs Area
Chapter 14 -Cache Valley
Chapter 15 -Malad Valley & Country to the West
Chapter 16 -Marsh Valley
Chapter 17 -Inkom & the Portneuf Narrows

Early summer scene of the Bear River and the Southern Bannock Range, Cache Valley, Idaho, taken looking west from the northwest of Preston. Weston Mountain is the high ridge in right background. The lower ridge, cut by two steep canyons, is composed of the Late Proterozoic Pocatello Formation. The West Cache normal fault runs north-south near the base of the mountains. This part of Cache Valley is mantled with several hundred feet of fine sands and silts deposited in lakes, the latest of which was Lake Bonneville. The Bonneville shoreline (5,090 feet) is a short way up the slope of the mountain. The Provo shoreline (4,740 feet) is the prominent horizontal line at the base of the mountains. The conspicuous terraces between the Provo shoreline and the present Bear River level (4,450 feet) were formed as Bear River incised the lacustrine sands and silts as the level of Great Salt Lake fell, (June 1984).