Publication Date:
2016-12-16
Description:
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.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Article
,
isiRev
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