Project Details
Projekt
Permafrost history in Arctic Siberia - insights from the cryogenic weathering record at El'gygytgyn Crater, NE Siberia
Applicant
Dr. Georg Schwamborn
Subject Area
Mineralogy, Petrology and Geochemistry
Term
from 2007 to 2009
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 36801406
I propose to determine climate variations expressed in variations of permafrost conditions in Arctic Siberia. Particularly I am interested in establishing a sedimentological method that allows estimating the degree of cryogenic weathering and palaeo soil temperatures through geologic time. My studies explore a lake sediment record from Elgygytgyn Crater lake, Arctic Siberia, spanning the last 300.000 years and representing the longest terrestrial palaeoclimate and -environment archive for the Arctic at present, permafrost sediments from the catchment spanning the last 14.000 years, and a set of surface samples representing modern conditions. I will study the following mineralogical properties in lake, permafrost, and surface sediments, which are considered to mirror long term periglacial dynamics in NE Siberia: (1) The ratio of quartz to feldspar in selected grain size fractions will be used as an indicator reflecting the degree of frost weathering. (2) Image analysis of scanning electron micrographs of particles will be performed to provide a quantification of quartz grain morphology and surface features stemming from frost weathering. (3) Heavy minerals will be used as provenance indicators to define changes in source rock composition and cryogenic detritus. The results prepare a fundamental tool that allows determining the intensity of permafrost conditions through Quaternary glacial cycles and estimating palaeo soil temperatures in the North Siberian Arctic. This is a conceptual outcome of future cores from ICDP funded deep drillings.
DFG Programme
Infrastructure Priority Programmes
