Simultaneous rupture along two conjugate planes of the Wharton Basin earthquake.
Analysis of broadband teleseismic data shows that the 18 June 2000 Wharton Basin earthquake, a moment magnitude 7.8 intraplate event in the region of diffuse deformation separating the Indian and Australian plates, consisted of two subevents that simultaneously ruptured two near-conjugate planes. This mode of rupture accommodates shortening by a mechanism different from that previously known elsewhere in the region. The larger subevent occurred on a fossil fracture zone, with a relatively high stress drop of about 20 megapascals, showing that large stresses can accumulate in regions of distributed deformation.
Robinson
D P
DP
Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, UK.
Henry
C
C
Das
S
S
Woodhouse
J H
JH