Crustal thickness across Iceland

Richard M. Allen (1), Guust Nolet (1), W. Jason Morgan (1), Kristin Vogfjord (1), Bergur H. Bergsson (2), Palmi Erlendsson (2), Gillian R. Foulger (3), Steinunn Jakobsdottir (2), Bruce R. Julian (4), Matt Pritchard (3), Sturla Ragnarsson (2), Ragnar Stefansson (2).

(1) Dept. Geosciences, Princeton University, USA. (2) Vedurstofa Islands, Reykjavik, Iceland. (3) Dept. Geological Sciences, University of Durham, UK. (4) U.S. Geological Survey, Menlo Park, CA, USA.

Abstract submitted to AGU Fall Meeting, December 1997.

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We use the HOTSPOT network to study crustal and uppermost mantle phases across Iceland. The arrival times are used to constrain a crustal velocity model including crustal thickness.

The HOTSPOT array is a PASSCAL network consisting of 29 broadband instruments distributed across Iceland; typical station spacing is 50 km. The network was installed in the summer of 1996 and will remain in place until the summer of 1998. Its coverage is complemented by the SIL network, a permanent network of 24 stations, operated by Vedurstofa Islands.

The combined networks provide excellent coverage of Iceland. We used this data to identify PmP, Pg, Pn and the shear wave equivalents on the numerous local earthquakes. These arrivals are then used to constrain the crustal velocity structure and depth to Moho. Preliminary results are shown.



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© Richard M Allen