| Summary: | Abstract: Sediment provenance at the Kronerbreen/Kongsvegen glaciers in Spitsbergen can be used to understand the effects that climate change can have on the sedimentation in fjords, and streams at northern latitudes. These sediments are directly related to glacial processes and reflect the conditions under which they formed. Such conditions are sensitive to global climate change, which is amplified in northern latitudes, creating a unique environment for climate change research. Quantitative provenance studies have never been carried out in the Kongsfjorden before, and can provide data for a better understanding of glacial processes and dynamics, and changes in erosional conditions. Particularly, sedimentation rates and sediment grain size distribution can help unravel the glacial history of the area. This study will focus on analyzing the grain size distribution of the material being deposited by the mentioned glaciers and finding the source rock of these sediments. Fine sediment was transported by streams and upflows identified in the field, and fed by the glaciers melting ice. On the other hand, coarser material ranging from cobble to boulder size was deposited by ice, moraines, and alluvial processes. Sediment and rock samples were collected during the months of July and August 2009, along the terminus of the glacier, and in the surrounding areas, respectively. Grain size analysis was performed on the samples using a Malvern Mastersizer with the resulting in different groups showing a change in particle size and sorting depending on the location along the glacier. This analysis is important as mineral composition and transportation is influenced by grain size. Electron microprobe studies were carried out on sediment grains to obtain a rough compositional profile of the sediments, and a first-order mineralogical make-up. The microprobe results provided us with information about composition of some of the minerals present, based on the content of Fe, Ca, K and Al derived from the erosion of the local lithologies. Chemical composition can distinguish sediments derived from different sources, and may ultimately be compared with representative rock samples taken from the moraines. Due to the limited accessibility to some areas, many geological units in the Kongsfjorden area have not been mapped or studied, limiting the possible comparisons with contributing material to the fjord’s seafloor. Remote sensing techniques were used to map lithologies in previously unmapped regions using ENVI®, and ASTER satellite imagery. A GER 3700 radiospectrometer was used to collect spectral properties of the rock samples. These properties were compared to the outcrops in the satellite imagery giving us an idea of the bedrock composition of the area. The results of our research can be compared with future studies in order to obtain information, regarding responses in the glacier dynamics and processes, related to climate change.
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