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The coastal section at Kapp Ekholm in Billefjorden is a key locality for the Quaternary stratigraphy of Svalbard and forms the backbone for the often-used glaciation curve for the western Barents Sea. Earlier work suggests that this is the only locality in Svalbard with evidence of four successive glaciations and intervening marine intervals found in superposition. Previous studies have disagreed on the correlation of units across the ravines cutting through the section. Correlation is complicated further by the lateral variation in sedimentary characteristics within the glacial units and the repetitive pattern of sedimentary facies. Despite the complex nature of the glacial deposits no detailed investigations of their sedimentology have been carried out previously. This study presents a reinvestigation of the Kapp Ekholm section based on fieldwork carried out in the summer of 2007. Our work is concentrated on the central part of the section where most previous investigations have disagreed on interpretation and correlation of units. The present study focuses on detailed sedimentological descriptions of the glacial deposits in order to interpret the depositional environment and aims at testing whether all these units are deposited as basal tills. Correct interpretation of the diamict deposits will have significant implications for reconstructing the magnitude of ice advances in the Billefjorden area and thus also for the understanding of the regional glaciation history. Detailed sedimentological logs have been measured from sections III, IV and V at Kapp Ekholm. Sedimentological descriptions, clast morphology, clast fabric and grain size analyses of the diamict units are used to distinguish between depositional environments. The sedimentary units have been traced laterally and measurements on deformation structures have been used to determine whether deposition was associated with actively moving ice. The present study confirms a fluctuation between glacial and marine phases as suggested in previous studies, but do not recognize the unit definitions and boundaries described previously. We present the new results and discuss the implications for the glaciation history of Svalbard.
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