HR: 10:35h
AN: S52B-02 [Abstracts]
TI: The Lithosphere of the NW-Atlantic and the Iceland Plume Track
AU: * Kind, R
EM: kind@gfz-potsdam.de
AF: GFZ Potsdam, Telegrafenberg, Potsdam, 14473
Germany
AB:
The dynamics of the North Atlantic is dominated by the Iceland plume and the
mid Atlantic spreading center separating the North American and Eurasian
lithospheric plates. An important parameter for understanding the
plume-lithosphere interaction is the thickness of the lithosphere which we
determine with very high accuracy. The new seismic technique of S receiver
functions (using S to P converted teleseismic waves, Li et al.2004) provides
images of the lithosphere-asthenosphere boundary (LAB) with as yet
unprecedented detail. The lithosphere under most of the Iceland and large parts
of central Greenland is about 80km thick. This is an unexpectedly large value
for Iceland since it is located on a mid ocean ridge. Our interpretation is
that the Icelandic lithosphere may not be oceanic in origin, but continental.
In the region of flood basalts in eastern Greenland, where the Iceland plume
track is proposed (Lawver and Mller 1994), the lithosphere is only 70km thick,
about 10 km less than in Iceland directly above the plume. We interpret this as
rejuvenation of the lithosphere along the plume track. At the coast of western
Greenland, the lithosphere thickens to 100-120km and no indication of the
Iceland plume track is found there.
DE: 8120 Dynamics of lithosphere and mantle--general
DE: 8121 Dynamics, convection currents and mantle plumes
DE: 7200 SEISMOLOGY
DE: 7218 Lithosphere and upper mantle
SC: Seismology [S]
MN: 2004 AGU Fall Meeting