Regulation of ice stream flow through subglacial formation of gas hydrates

Monica Winsborrow, Karin Andreassen, Alun Hubbard, Andreia Plaza-Faverola, Eythor Gudlaugsson, Henry Patton

Research output: Contribution to journalArticlepeer-review

30 Citations (SciVal)
13 Downloads (Pure)

Abstract

Variations in the flow of ice streams and outlet glaciers are a primary control on ice sheet stability, yet comprehensive understanding of the key processes operating at the ice-bed interface remains elusive. Basal resistance is critical, especially sticky spots-localized zones of high basal traction-for maintaining force balance in an otherwise well-lubricated/high-slip subglacial environment. Here we consider the influence of subglacial gas-hydrate formation on ice stream dynamics, and its potential to initiate and maintain sticky spots. Geophysical data document the geologic footprint of a major palaeo-ice-stream that drained the Barents Sea-Fennoscandian ice sheet approximately 20,000 years ago. Our results reveal a ∼250 km2 sticky spot that coincided with subsurface shallow gas accumulations, seafloor fluid expulsion and a fault complex associated with deep hydrocarbon reservoirs. We propose that gas migrating from these reservoirs formed hydrates under high-pressure, low-temperature subglacial conditions. The gas hydrate desiccated, stiffened and thereby strengthened the subglacial sediments, promoting high traction-a sticky spot-that regulated ice stream flow. Deep hydrocarbon reservoirs are common beneath past and contemporary glaciated areas, implying that gas-hydrate regulation of subglacial dynamics could be a widespread phenomenon.

Original languageEnglish
Pages (from-to)370-374
Number of pages5
JournalNature Geoscience
Volume9
Issue number5
Early online date11 Apr 2016
DOIs
Publication statusPublished - 01 May 2016

Fingerprint

Dive into the research topics of 'Regulation of ice stream flow through subglacial formation of gas hydrates'. Together they form a unique fingerprint.

Cite this