BEEN THERE, DUNE THAT: ALBANY PINE BUSH PRESERVE DUNE FIELD EVOLUTION USING GPR

The Albany Pine Bush Preserve (APBP) is located between the cities of Schenectady and Albany, eastern New York and is a unique pine barren landscape with parabolic dunes up to several km in length. About 15 kya, as Glacial Lake Iroquois drained eastward through the Mohawk valley, a delta was created in Glacial Lake Albany. Dune development commenced as the lake level declined and exposed the deltaic sediments to strong NW to SE winds. We hypothesize that the dune field stabilized at about 11 kya, preserving the parabolic nature of the dunes and their relationships to the landscape.

The main objectives of this research were to determine: 1) the relationship of the dunes to Glacial Lake Albany and the delta and 2) is there evidence for multiple activation and/or stabilization phases and variation in wind direction.

We used DEM data derived from New York State 1-m LiDAR coverage to evaluate the landscape and select locations for acquiring ground penetrating radar (GPR) imaging of the subsurface architecture. We collected >5 km of 160 MHz GPR data and ~1 km of 450 MHz data using the MALA Ground Explorer GPR system. The GPR data were integrated with the DEM data where we evaluated the subsurface characteristics and their relationship with the surface expression of the dune field and the underlying surface.

Preliminary results suggest that variation in the internal structure of the dunes at APBP is related to the postglacial transition. Currently, we are evaluating the different facies observed in the GPR records to understand whether or not they represent overlapping dunes, a variation of facies within individual dunes and differences in dune facies from underlying delta and lacustrine sediments. Previous research indicates delta topsets are only a few meters below the surface in interdune areas.