Northeastern Section (45th Annual) and Southeastern Section (59th Annual) Joint Meeting (13-16 March 2010)

Paper No. 7
Presentation Time: 8:00 AM-12:05 PM


BARON, Gregory John, Environmental Studies, Gettysburg College, 300 N Washington Street Box 124, Gettysburg, PA 17325, PRINCIPATO, Sarah M., Environmental Studies, Gettysburg College, 300 N. Washington St, Box 2455, Gettysburg, PA 17325 and JONES, Brittany Robinson, Environmental Studies, Gettysburg College, 300 N Washington Street Box 1113, Gettysburg, PA 17325,

The purpose of this study was to reconstruct a Holocene climate proxy record from peat deposits near Penobscot, Maine. A 129 cm core (EB-09-01) was collected from an abandoned peat mine using a Russian Corer. The core was sub-sampled at approximately 4 cm intervals, with an increased sampling resolution when a distinct change in stratigraphy of the peat was visible. A radiocarbon date of a piece of wood at 118 cm is 5920±50 14C yrs BP, indicating that every 10 cm of peat corresponds to approximately 500±50 years. In the laboratory, sedimentology analyses, including water content and loss-on-ignition (LOI), were preformed for each sub-sample of peat. A high value for LOI represents a high percentage of carbon in the peat, which is indicative of a period with high productivity and warm temperature. A low value for LOI represents a low percentage of carbon in the peat, which is interpreted as a period with a low level of productivity and cool temperature. Preliminary analysis of water content data shows an overall increase in water content with depth from 76% water content at the surface to 89% content in the lowest 40cm of the core, with some major and minor fluctuations throughout the core. Initial analysis of LOI reveals a similar trend to water content, with an LOI of 87% at the surface and a sharp increase with depth. LOI increases to about 98% at a depth of 20cm, and remains at that level throughout the remainder of the core with small variations. The degree of humification corresponds to the overall decomposition of the samples, providing a proxy for the precipitation during approximately the last 6000 years. Measurements of absorbance and percent light transmission are analyzed using a Spectronic 20 Genesys at 540 nm to determine the degree of humification. Humification analyses are currently in progress.