2001 FALL MEETING ANNOUNCEMENT NORTHEAST SECTION - AIPG

Wednesday, October 17, 2001
Geology of the Beach and Cliffs at Caumsett State Park
by Gilbert N. Hanson, Ph.D.
Department of Geosciences, SUNY Stony Brook
Caumsett State Park Lloyd Neck, Town of Huntington, New York
OPEN TO ALL AIPG MEMBERS AND OTHER INTERESTED SCIENTISTS

The cliffs at Caumsett State Park are situated on the north shore of Long Island facing Long Island Sound and Connecticut. While Long Island Sound presently is a body of seawater, some 20,000 years ago it was a fresh-water lake fed by the advancing glacier, which formed the Harbor Hill Moraine in northern Long Island. As the glacier advanced, it pushed forward the underlying Cretaceous clays and sands and the overlying glacial lake sediments deforming them. The lake sediments include sands and gravels of a Gilbert-type delta formed in the proglacial lake. The glacier continued to advance and overrode the area depositing till near the top. The till is overlain by wind-blown loess into which cliff swallows prefer to burrow. The sediments and the boulders along the beach are the result of the continued erosion of the cliffs associated with continued sea level rise throughout the latest Pleistocene and Holocene. More information regarding the geology of Caumsett State Park is available at http://pbisotopes.ess.sunysb.edu/esp/.