Frictional melting during the rupture of the 1994 bolivian earthquake

نویسندگان

  • Kanamori
  • Anderson
  • Heaton
چکیده

The source parameters of the 1994 Bolivian earthquake (magnitude Mw = 8.3) suggest that the maximum seismic efficiency eta was 0.036 and the minimum frictional stress was 550 bars. Thus, the source process was dissipative, which is consistent with the observed slow rupture speed, only 20% of the local S-wave velocity. The amount of nonradiated energy produced during the Bolivian rupture was comparable to, or larger than, the thermal energy of the 1980 Mount St. Helens eruption and was sufficient to have melted a layer as thick as 31 centimeters. Once rupture was initiated, melting could occur, which reduces friction and promotes fault slip.

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عنوان ژورنال:
  • Science

دوره 279 5352  شماره 

صفحات  -

تاریخ انتشار 1998