77 Limnogeology (Posters)

Wednesday, 20 March 2013
8:00 AM - 12:00 PM
Grand Ballroom South

A POLLEN PROFILE FROM GLOVERS POND, WARREN CO., NORTHERN NJ: CORRELATION WITH OTHER PALEOCLIMATE PROXIES

Paper number: 77-5
Program: Technical Sessions
Time: 8:00 AM – 12:00 PM

Authors

Abstract

Glovers Pond lies in a well studied, post-glacial, marl lake basin which developed in the Valley and Ridge Province of northern NJ following the draining of Glacial Lake Pequest II from its highest elevation at ~180 m above MSL. Pequest II was fed from melt of the Pequest Sublobe at its position approximating the Turtle Pond Ice Margin (Cotter, et al., 1986) Rock flour overlying till began basin filling as blue clay, followed by organic rich green/brown clay representing sedimentation under continued influence of meltwater from the increasingly distal ice margin resulting in a warmer water mass. Reduction of glacial melt influx is marked by cessation of sand deposition at 5.25 m depth in core C-I-1 where it represented the distal margin of the Turtle Pond delta. Loss of a sand source suggests establishment of the ancestral Bear Creek and Pequest River drainages had taken place. Sand never reached the central basin, site of the 5.9-m-long core, C-Lk-3, from which pollen was sampled. This is the closest pollen record to the LGM in northwestern NJ.

Blue clay between 5.90-5.24 m contained no pollen; the initial pollen record at 5.14 m was insufficient to characterize. The unit correlated to 14,720 C14 years BP in another core. For reasons of cost, analysis was begun at 2.94 m in olive gray clay dominated by spruce and pine . Oak began earlier at this protected site correlated with the transition to gyttja deposition between 2.84 – 2.76 m and dominated explosively at 11,430 ±410 C14 years BP. The YD is marked by reduction in oak and brief expansion of alder, pine, spruce and birch. Above 1.7 m the region was covered by northeastern oak hemlock mixed hardwood forest. An attempt will be made to correlate proxies using oribatid mites, chironomid larval temperature data and isotope data from four additional cores in the basin with the complete pollen record of C-Lk-3.