CHARACTERISTICS OF DIAMICTON FROM VESTFIRDIR AND THE MAINLAND OF ICELAND: IMPLICATIONS FOR PROVENANCE

The purpose of this study is to compare diamicton samples from three different regions of Iceland in order to determine provenance and ice flow paths. Multiple samples were collected from four sites: two from Vestfirdir (Reykjarfjordur and Kaldalon), one from north Iceland (Hvammstangi), and one from south Iceland (Solheimajokull). A total of 43 samples were analyzed for water content, magnetic susceptibility, and organic and inorganic content (loss on ignition). The fabric of elongate clasts was measured in the Hvammstangi site. Sedimentology data were statistically analyzed to determine variability based on location and internal variability within each site. The diamicton samples from Hvammstangi contained the lowest average water content, 9.94% and the highest mass magnetic susceptibility, 111.68 ×10-6 cgs. The samples from Solheimajokull had the highest average water content, 16.67 % and the lowest mass magnetic susceptibility, 28.57 ×10-6 cgs. This is not surprising because samples from Solheimajokull were taken from the margin of an active outlet glacier. Average water content in diamicton samples and mass magnetic susceptibility from Vestfirdir were intermediate compared to sites located on the mainland of Iceland. Samples from Reykjarfjordur and Kaldalon had an average water content of 16.41% and 13.74% and mass magnetic susceptibility of 87.12 ×10-6 cgs and 53.52 ×10-6 cgs respectively. Loss on ignition measurements on a subset of samples demonstrate very low values of organic and inorganic carbon, and additional analyses are in progress. Grain size analyses will be measured on a subset of samples from each site. Based on the sedimentology data, there are clear differences in the properties of diamicton samples from Vestfirdir compared to the mainland of Iceland. Internal variability of diamicton units is apparent, but the magnitude of variability differs from site to site.