Holocene Glacial and Paleoclimate Reconstructions in the North Cascades, Washington

Hal Wershow

Central Oregon Community College

5:30 pm social hour

7:00 pm presentation

The glaciers of the North Cascades are a critical source of meltwater for surrounding ecosystems and human uses, especially during the otherwise dry Cascadian summers. However, the Holocene history of these glaciers is poorly understood, partly because most glacial records rely on preserved moraines and are therefore discontinuous. COCC geology instructor Hal Wershow will discuss how he reconstructed Holocene fluctuations of North Cascades glaciers from glaciolacustrine sediments (i.e., rock flour) in Lyman Lake, which drains the Lyman Glacier. These reconstructions give us new insights on Holocene glacial advances and retreats in the North Cascades.