Existence of low-velocity zones under the source areas of the 2004 Chuetsu and 2007 Chuetsu-oki earthquakes inferred from travel-time tomography

Mathematics – Logic

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

1

Scientific paper

Travel-time tomography reveals the presence of highly heterogeneous seismic velocity structures around the source areas of the 2004 Chuetsu and 2007 Chuetsu-oki earthquakes. A prominent low-velocity zone present below the Moho under the source areas of the two events is probably formed by fluids being conveyed through a small-scale upwelling in the mantle wedge. A low-velocity zone distributed in the lower crust below each source area is attributable to fluids supplied from the uppermost mantle to the source area. Since this region with these two source areas is exceptional in that the low-velocity zone is distributed in the uppermost mantle but no Quaternary volcanoes are formed at the surface, a relatively large amount of fluids may be stored below the source areas. These localized fluids may have reduced the strength in the lower crust as well as in the fault zones in the upper crust and, consequently, have promoted a brittle failure in the seismogenic layer. Relocated hypocenters of aftershocks of the two events become several kilometers shallower than the original locations determined by the Japan Meteorological Agency, suggesting the importance of using the three-dimensional velocity model in locating the hypocenter.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Existence of low-velocity zones under the source areas of the 2004 Chuetsu and 2007 Chuetsu-oki earthquakes inferred from travel-time tomography does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Existence of low-velocity zones under the source areas of the 2004 Chuetsu and 2007 Chuetsu-oki earthquakes inferred from travel-time tomography, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Existence of low-velocity zones under the source areas of the 2004 Chuetsu and 2007 Chuetsu-oki earthquakes inferred from travel-time tomography will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-746427

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.