000002941 001__ 2941
000002941 005__ 20160921074147.0
000002941 0247_ $$2DOI$$a10.1093/gji/ggw214
000002941 037__ $$aSCART-2016-0019
000002941 100__ $$aLombardi, D.
000002941 245__ $$aBimodal pattern of seismicity detected at the ocean margin of an Antarctic ice shelf
000002941 260__ $$c2016
000002941 520__ $$aIn Antarctica, locally grounded ice, such as ice rises bordering floating ice shelves, plays a major role in the ice mass balance as it stabilizes the ice sheet flow from the hinterland. When in direct contact with the ocean, the ice rise buttressing effect may be altered in response of changing ocean forcing. To investigate this vulnerable zone, four sites near the boundary of an ice shelf with an ice rise promontory in Dronning Maud Land, East-Antarctica were monitored for a month in early 2014 with new instruments that include both seismic and GPS sensors. Our study indicated that this transition zone experiences periodic seismic activity resulting from surface crevassing during oceanic tide-induced flexure of the ice shelf. The most significant finding is the observation of apparent fortnightly tide-modulated low-frequency, long-duration seismic events at the seaward front of the ice rise promontory. A basal origin of these events is postulated with the ocean water surge at each new spring tide triggering basal crevassing or basal slip on a local bedrock asperity. Detection and monitoring of such seismicity may help identifying ice rise zones vulnerable to intensified ocean forcing.
000002941 536__ $$aBELSPO BR/$$c132/$$fPI/SMEAIS
000002941 594__ $$aNO
000002941 6531_ $$aseismic cycle
000002941 6531_ $$atransient deformation
000002941 6531_ $$atides and planetary waves
000002941 6531_ $$aglaciology
000002941 6531_ $$afracture and flow
000002941 6531_ $$aAntarctica
000002941 700__ $$aBenoit, L.
000002941 700__ $$aCamelbeeck, T.
000002941 700__ $$aMartin, O.
000002941 700__ $$aMeynard, C.
000002941 700__ $$aThom, C.
000002941 773__ $$c1375-1381$$pGeophysical Journal International$$v206$$y2016
000002941 8560_ $$fthierry.camelbeeck@observatoire.be
000002941 905__ $$apublished in
000002941 980__ $$aREFERD