|
|
||||||||
1 Department of Geological
Sciences
University of Texas at El Paso
El Paso, Texas 79968-0555
(D.I.D, A.M.V.)
2 GX Technology Corporation
2101 CityWest Blvd.
Building III, Suite 900
Houston, Texas 77042
(A.M.V.)
We have relocated over 8600 earthquakes occurring between 1964 and 1999
at depths >25 km within
100 km of Anchorage, Alaska,
using the double- difference technique. The relocated seismicity reveals
important details of the subducting Pacific plate and Yakutat blocks
including clustering of seismicity within the Pacific plate mantle,
northeast- and northwest-striking near-vertical faults within the
Pacific plate crust, and a region of intense deformation associated with
the southwestern edge of the Yakutat block. Stress analyses from the
direct inversion of first- motion data and from inversion of focal
mechanisms for 713 events indicates a rotation of the maximum
compressive stress direction from a trench parallel direction
(northeast) in the southwestern portion of the study area to an
eastwest direction near the southwestern edge of the Yakutat
block located just north of Anchorage. Regions of the Pacific plate
mantle that produced Mw >6.4 earthquakes in
1934 and 1954 continue to be seismically active.
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |