Using Sedimentology and GIS Analysis to Interpret Paleo-Ice Flow in Northern Iceland

Alyson G. Hampsch, Gettysburg College

Environmental Studies Honors Thesis

Faculty Advisor: Professor Sarah Principato

Abstract

This study uses Geographic Information System (GIS) and sedimentology analyses to determine paleo-ice flow paths in northern Iceland during the Last Glacial Maximum (LGM). Till samples were collected from three regions south of Hunafloi: the valleys Svinadalur and Vatnsdalur, and the Hrutafjardarhals highlands. Forty five samples were analyzed for water content, organic content, magnetic susceptibility, and grain size. There are notable differences in the magnetic susceptibility and organic material in the Svinadalur samples compared to Hrutafjardarhals and Vatnsdalur, likely from differences in the bedrock composition. ArcGIS and ENVI were used to quantify characteristics of streamlined landforms in Svinadalur, using a digital elevation model (DEM), aerial photographs, and satellite data. GIS analyses of streamlined landforms include measurements of length, width, elongation ratio, orientation, and density. A total of 537 streamlined landforms have been identified in the Svinadalur valley. The elongation ratio is high, with both drumlins and megascale glacial lineations (MSGL) identified. The orientation is northwest-southeast and the density of the landforms is high. The landform characteristics provide evidence for the existence of an ice stream in the Svinadalur valley during the LGM, feeding ice into the Hunafloi bay.