LOSS-ON-IGNITION AND HUMIFICATION OF A PEAT CORE FROM QUODDY HEAD STATE PARK, MAINE

The purpose of the study was to reconstruct a climate proxy record for the Holocene from a peat core sampled at Quoddy Head State Park, Maine. A 300 cm core was recovered using a Russian Corer. The core was subsampled in the field at approximately 4 cm intervals. An AMS radiocarbon age of 9.32 ± 0.05 ¹⁴C ka BP was obtained from a preserved wood piece at a depth of 274 cm. A linear age model was generated for the core, indicating that it contains a record of approximately the past 10.25 ¹⁴C ka BP. Water content, mass magnetic susceptibility, loss-on-ignition (LOI), and degree of humification of the core are in the process of being analyzed in the laboratory. The mass magnetic susceptibility of the peat samples is negligible. Water content through the core is variable, but there is a general trend of increasing water content until 6.50 ¹⁴C ka BP, where the trend reversed, with decreasing water content. LOI is used to interpret climate variability. An increase in LOI suggests a warmer climate with higher productivity, and a decrease in LOI indicates lower productivity associated with a cooler climate. There were abrupt decreases in LOI at approximately 10.00 ¹⁴C ka BP , 8.60 ¹⁴C ka BP , 1.70 ¹⁴C ka BP , and 0.60 ¹⁴C ka BP , suggesting a cooler climate. The degree of humification of the peat is used to reconstruct precipitation patterns during the Holocene. Less humified peat is interpreted as increased precipitation, and highly humified peat is interpreted as less precipitation. To determine the degree of humification, the absorbance and transmission of extracted humic acids from the peat are currently being analyzed using a Spectronic 20 Genesys at λ = 540 nm.