History: Rise and fall of Tahoe through geological lens

Publisher’s note: This is reprinted from the Fall Quarterly 1977 Lake Tahoe Historical Society newsletter.

Temperamental weather failed to discourage 75 friends of the Lake Tahoe Historical Society who turned out to enjoy the 1977 opening of the Log Cabin Museum, Star Lake Road off Highway 50, on May 22.

Museum Director Henry Newburgh greeted visitors and discussed museum displays.

Board members Pat Amundson, Ron Porter, Carolyn Nagy, Martha Reinholdt, Brooke Laine, and Linda Mendizabal served refreshments and assisted with brisk sales of memberships, books, and posters. This year’s poster, printings of two of the Society’s most popular photos, were well received.

Visitors adjourned to the school district board room for a slide presentation by Dr. Jonathan Davis of the University of Nevada. Davis recently completed his doctoral thesis in geology and archeology at the University of Idaho.

An enlightening question and answer session followed the presentation. Some of the group ignored the spring rain and accompanied Davis to archeological sites at Kiva Beach and Fallen Leaf campground.

Davis highlighted the prehistoric activity of the area. He noted volcanic evidence predates formation of the lake. Millions of years ago, the Sierra Nevada Mountains were uplifted in a single block with “slivers” breaking off at the northern end. One such sliver is the Carson Range. The Tahoe Basin is a result of faulting, Davis explained.

Either the area never uplifted with the batholith or it fell back again. More than 100 year ago, an icecap covered Glen Alpine and Desolation Valley. Glen Alpine is a classic glacial valley with Emerald Bay and Fallen Leaf Lake glacial imprints, the geologist said.

The present Tahoe landscape is about 6,000 years old and a few radio-carbon dates go back 8,000 years, Davis said.

The Washoe Indians summered at Lake Tahoe, establishing fishing camps at the lake’s edge. Those sites older than 6,000 years presumably drowned with the natural rise in the lake level.

The South Shore is a drowned coast, evidence by the muddy shoreline waters and meadows bounded by Taylor and Tallac Creeks, the geologist said. The weather was hotter and dried up to 4,000 years ago.

The Washoes rarely wintered in Tahoe, dispersing after the fish runs, from Honey Lake to Topaz Lake. Some groups lived near the hot springs in Carson Valley, hunting and gathering plants in early fall, he said.

They gathered pine nuts from the Virginia Mountains for winter food stores in late fall.

Tahoe is symbolic because it was the only place the entire Washo nation gathered during their annual cycle, Davis said.

— Linda Mendizabal