--> Abstract: Climate Cycles and Events in the Cenozoic of the Yermak Plateau, Arctic Ocean: X-Ray Fluorescence Scanner Data of ODP Sites 910 and 911 as a Stratigraphic Tool, by C. M. Vogt, J. Knies, J. Matthiessen, and H-J. Brumsack; #90096 (2009)

Datapages, Inc.Print this page

Climate Cycles and Events in the Cenozoic of the Yermak Plateau, Arctic Ocean: X-Ray Fluorescence Scanner Data of ODP Sites 910 and 911 as a Stratigraphic Tool

Christoph M. Vogt1, Jochen Knies2, Jens Matthiessen3, and Hans-Jürgen Brumsack4
1Crystallography/Geosciences, University of Bremen, Bremen, Germany.
2Norwegian Geological Survey, Trondheim, Norway.
3Geosciences, Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany.
4Geochemistry, Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl-von-Ossietzky-University, Oldenburg, Germany.

Based on a revised chronostratigraphy and a compilation of borehole data from the Barents Sea continental margin, we proposed for the first time a coherent general glaciation model for the Barents Sea ice sheet over the past 3.5 million years (Ma) Knies et al. (in press). Three principal phases of ice growth were suggested:

(1) The initial build-up phase, covering mountainous regions and reaching the coastline/shelf edge in the northern Barents Sea during shortterm glacial intensification, is concomitant with the onset of the Northern Hemisphere Glaciation (3.6-2.4 Ma).
(2) A transitional growth phase (2.4-1.0 Ma), during which the ice sheet expanded towards the southern Barents Sea and reached the northwestern Kara Sea (see Vogt & Knies 2008 for a detailed sedimentation process description and Krylov et al., 2008 for the general Tertiary to Quaternary trends).
(3) Finally, large-scale glaciation in the Barents Sea occurred after 1 Ma with repeated advances to the shelf edge.

Despite large obstacles to prepare a high resolution chronostratigraphy in Arctic Ocean sediments beyond 300,000 years (Knies et al., 2007,Matthiessen et al.,2009), we are now able to identify changes down to milenial scale resolution and back to 3.5 Ma in the Yermak Plateau and Fram Strait region.

Marine Isotope Stage (MIS) 6 was the youngest very large glaciation of the Barents-Kara Sea region. The Kara Sea outlet was completely blocked and very small amounts of its typical mineral assemblage (c.f. Knies & Vogt 2003). Local sources dominate (c.f. Vogt et al., 2001). These are usually combined with indicators of warmer Atlantic Water influx including biogenic carbonates (mainly calcite, Vogt et al., 2001 and references therein).

By tracing typical changes in the K/Ca-ratio and despite the complications from carbonate/ calcite dissolution effects we can find plenty of large deglacial sequences in the ODP 911A Hole records may be down to the Miocene.

Based on our latest publication (Knies et al., in press) and in cooperation with us a Norwegian mainly stratigraphic research project was initiated to better understand the age of three phases of Northern Hemisphere glacation and in particular the correlation of certain distinc regional seismic unconformaties to the ODP holes of the Yermak Plateau and the western Barents Sea slope. See the presentation of Knies et al.. For all citations visit http://www.geo.uni-bremen.de/FB5/kristall/cvogt/cvpub.htm.


AAPG Search and Discover Article #90096©2009 AAPG 3-P Arctic Conference and Exhibition, Moscow, Russia