Stratigraphic Chronology and Mechanisms of Formation of Bottom Sediments at the Mouth of the Grøndalen River (Grøn-Fjord, West Spitsbergen) during the Period of Climatic Changes

The results of the study of bottom sediments and water of the estuary of the Grøndalen River (Grøn-Fjord, West Spitsbergen) are presented. The stratigraphic features of the sedimentary strata are determined. The chronology of changes in geoecological environmental conditions has been established using radioisotope dating methods. The main factors influencing sedimentation in the study area are air temperature and precipitation during the period of predominance of low temperatures. It is shown that climate fluctuations determine the chronological sequence of the sedimentation rate and the change of the lithotype of the bottom sediment toward fine fractions.