Arctic megaslide at presumed rest

Published version. Source at http://doi.org/10.1038/srep38529 . License CC BY 4.0 . Slope failure like in the Hinlopen/Yermak Megaslide is one of the major geohazards in a changing Arctic environment. We analysed hydroacoustic and 2D high-resolution seismic data from the apparently intact continenta...

Full description

Bibliographic Details
Published in:Scientific Reports
Main Authors: Geissler, Wolfram H., Gebhardt, Catalina, Gross, Felix, Wollenburg, Jutta, Jensen, Laura, Schmidt-Aursch, Mechita, Krastel, Sebastian, Elger, Judith, Osti, Giacomo
Format: Article in Journal/Newspaper
Language:English
Published: Springer Nature 2016
Subjects:
Online Access:https://hdl.handle.net/10037/10744
https://doi.org/10.1038/srep38529
Description
Summary:Published version. Source at http://doi.org/10.1038/srep38529 . License CC BY 4.0 . Slope failure like in the Hinlopen/Yermak Megaslide is one of the major geohazards in a changing Arctic environment. We analysed hydroacoustic and 2D high-resolution seismic data from the apparently intact continental slope immediately north of the Hinlopen/Yermak Megaslide for signs of past and future instabilities. Our new bathymetry and seismic data show clear evidence for incipient slope instability. Minor slide deposits and an internally-deformed sedimentary layer near the base of the gas hydrate stability zone imply an incomplete failure event, most probably about 30000 years ago, contemporaneous to or shortly after the Hinlopen/Yermak Megaslide. An active gas reservoir at the base of the gas hydrate stability zone demonstrate that over-pressured fluids might have played a key role in the initiation of slope failure at the studied slope, but more importantly also for the giant HYM slope failure. To date, it is not clear, if the studied slope is fully preconditioned to fail completely in future or if it might be slowly deforming and creeping at present. We detected widespread methane seepage on the adjacent shallow shelf areas not sealed by gas hydrates.