Erosion on the Oregon coast has exposed several paleosols (ancient soil deposits) containing well-preserved tree trunks. Some trunks are of Holocene age [Hart and Peterson, 1997], while others are much older. These macrofossil deposits contain clues to tectonic activity, paleovegetation patterns, coastal erosion, and climate evolution.
This article describes a paleosol located near Cape Perpetua, Oregon, containing trunks dated at prior to 50,000 B.P. The forest appears to have been buried during a catastrophic debris flow and preserved due to anoxia.