69 Paleolimnological Studies of Climate Variability and Environmental Response (Posters)

Tuesday, 21 March 2017
1:30 PM - 5:30 PM
Grand Ballroom, 17th Floor

PREHISTORIC HUMAN CULTURAL SHIFTS IN THE MID-ATLANTIC: EVIDENCE OF CLIMATE INFLUENCE ON ARCHAIC CULTURES IN NEW JERSEY INFRERRED FROM A 15,000-YEAR LAKE SEDIMENT CORE

Paper number: 69-16
Program: Theme Sessions
Time: 1:30 PM – 5:30 PM

Authors

Abstract

We present a local lacustrine record from Lake Blauvelt (LB), Franklin Lakes, New Jersey, which records past regional climate variability since ~15,000 years before present (kyr). Several paleoclimate proxies of regional lake recharge, weathering, and vegetation activity were extracted from the core at 3-4 cm increments (~50-100-year temporal resolution) and include analyses of sediment grain size, organic carbon and nitrogen content, nitrogen and carbon isotopes, and paleomagnetism. These proxies reveal similar patterns of variability throughout the record, whereby periods of larger-grained sediment input into the lake were synchronous with higher organic carbon and nitrogen fluxes (and vice versa), indicating both proxies likely reflect changes in lake recharge and weathering rates. These patterns are validated by similar Holocene patterns in C/N, magnetic susceptibility, and sedimentation rates. Together, the data indicate the Younger Dryas epoch (~12.8-11.5 kyr) was characterized by generally dry conditions, which culminated with a rapid transition to increased lake recharge during the early Holocene (~10 kyr). Superimposed upon a general increasing trend in LB lake levels throughout the Holocene is a major step-change at ~4.5-5 kyr, signifying an abrupt transition to higher lake levels that is matched by increased storm frequency in New England and declining regional air temperatures. These patterns are coeval with an abrupt increase in temperatures in the Pacific Northwest and tropical Eastern Pacific, indicating a strong role for the Pacific Decadal Oscillation (PDO) in this shift.

This proxy data when combined and analyzed serves as a context for the study of human culture in the local area from the Paleo-Indian Period to the Late Woodland Period, detailed within. Rather than using only publicly available C14 dates, our study hopes to bring greater light to “gray literature” and collections, at least in northern NJ. The addition of new archaeological data from the region may help in creating a centralized database or foundation for research of settlement patterns as well as the establishment of trade networks and technological shifts in northern New Jersey.

Geological Society of America Abstracts with Programs. Vol. 49, No. 2

doi: 10.1130/abs/2017NE-291220

© Copyright 2017 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.