Near Preston in Franklin County, Idaho — The American West (Mountains)
Old Delta Sediments
Photographed By Barry Swackhamer, June 21, 2017
1. Old Delta Sediments Marker, missing
Diverted into this valley by lava flows, the Bear River deposited a huge, mostly red clay delta here where it entered a vast inland sea that covered much of Utah. About 14,500 years ago , its shoreline suddenly went down about 80 feet following an enormous discharge into the Snake River. From then on, it gradually receded to become the Salt Lake. Bear River then had to cut through and erode its old delta, forming the steep sides and gullies you see here today.
Erected by Idaho Department of Transportation. (Marker Number 432.)
Topics and series. This historical marker is listed in these topic lists: Natural Features • Paleontology • Waterways & Vessels. In addition, it is included in the Idaho State Historical Society series list.
Location. 42° 9.844′ N, 111° 49.904′ W. Marker is near Preston, Idaho, in Franklin County. Marker is at the intersection of U.S. 36 at milepost 12.9 and North Sage Ridge Road, on the right when traveling north on U.S. 36. Touch for map. Marker is in this post office area: Preston ID 83263, United States of America. Touch for directions.
Other nearby markers.
this page online
Credits. This page was last revised on July 19, 2017. It was originally submitted on July 19, 2017, by Barry Swackhamer of Brentwood, California. This page has been viewed 198 times since then and 13 times this year. Photo 1. submitted on July 19, 2017, by Barry Swackhamer of Brentwood, California.
