Lithological and Mineralogical Characteristics of Bottom Sediments in Ice-Scoured Areas in the Southwestern Kara Sea

Sedimentary material sampled in the southwestern Kara Sea both directly in ice scours and on background surfaces undisturbed by ice scouring has been studied. Based on studies of the physical properties and lithomineralogical features of bottom sediments in the ice scours, the boundary of ice scouring impact (exaration contact) was identified. Based on the X-ray diffraction analysis of <0.001-mm fraction, the chlorite structure is sensitive to temperature in samples taken below this contact, in contrast to the overlying samples. Together with the results of microscopic studies of thin sections, this fact indicates the neoformation of chlorite. The presence of secondary chlorite in near-surface conditions can suggest the glaciodynamic impact (pressure) of iceberg keels on bottom sediments. Microstructures of the ice scour sediments differ both in different test sites of the study area and within the same scour, depending on the location of sampling point on the transverse profile of morphosculpture.