| Summary: | Abstract: Svalbard is a Norwegian island archipelago located at 79°N whose glaciers are highly susceptible to climate fluctuations. Glaciers located in Svalbard sit between warm water from the south and cold polar water from the north. This position increases their sensitivity to climate fluctuations. Due to amplified and continuous climatic warming at high latitudes, the glaciers of Svalbard are prime subjects for understanding not only glacial dynamics, but also the effects of contemporary climate change. Tidewater glaciers are dynamic systems, with ice retreating and glacial and subglacial streams continuously shifting. An understanding the current spatial distribution of sediment sources will aid in interpreting sediment core data. From this we can infer former climactic and environmental conditions. Kongsfjorden is a 15 km long fjord located in northwest Svalbard, with the glaciers of Kronebreen and Kongsvegen forming the head of the fjord. There are two main sediment sources that discharge sediment rich water into the fjord: a subglacial stream that forms an upwelling plume at the calving margin, and a glacial stream that forms a prograding delta complex from the southern margin of Kongsvegen glacier. This project aims to characterize these sediment sources based on the clay mineralogy found in the samples and to map their spatial distribution in the fjord. Sediment from the sediment sources was collected using water samples and vacuum filtering the water in order to catch the sediment. Sediment from the fjord floor was collected using an Eckman box-corer attached to a wire and winch system. Twenty-nine samples were collected, dried, and sieved to separate the silt and clay fraction from the coarser sediment. Using X-ray diffraction, the clay mineralogy of the samples was found to be composed primarily of illite and chlorite. The 001 diffraction peak of chlorite is not visible in several samples. Chlorite is commonly found in metamorphic rocks, which are present as a bedrock source underneath Kronebreen glacier, but not Kongsvegen. The absence of the 001 chlorite peak could be due to sample preparation or a weaker concentration of chlorite in those samples. Overall, the sediment in front of the calving margin of the Kronebreen and Kongsvegen glacier complex is well mixed and the sediment distributed by the upwelling plume and Kongsvegen Delta are not differentiable in the box cores samples
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