HR: 1340h
AN: S23A-0283 [Abstracts]
TI: Earthquake Probabilities and Magnitude Distribution in 100a along the Haiyuan Fault, northwestern
China
AU: * Ran, H
EM: ranhl@tom.com
AB:
The Haiyuan fault is a major seismogenic fault in north-central China. One of the most devastating great earthquake in 20th
century occurred near Haiyuan in northwestern China in December 16, 1920. More than 220000 people were killed and thousands
of towns and villages were destroyed during this devastating earthquake. A 230 km long left-lateral surface rupture zone
formed along the Haiyuan fault during the earthquake with maximum left lateral displacement of 10 m.
In recent years, some researchers have studied the paleoseismology along the Haiyuan fault and revealed a lot of
paleoearthquake events. All available information allows more reliable analysis of earthquake recurrence interval and
earthquake rupture patterns along the Haiyuan fault. Based on fault geometry, segmentation pattern, and paleoearthquake
events along the Haiyuan fault we can identify three scales of earthquake rupture: rupture of one segment, cascade rupture of
two segments, and cascade rupture of entire fault (three segments), and obtain the earthquake recurrence intervals of these
scales of earthquake rupture.
The earthquake probability and magnitude distribution in 100-year along the Haiyuan fault can be obtained through weighted
computation, by applying these paleoseismological information mentioned above, using Possion and Brownian passage time model
and considering different rupture patterns. The result shows that the earthquakes probability of is about 0.035 in 100-year
along the Haiyuan fault.
DE: 7221 Paleoseismology
DE: 7223 Seismic hazard assessment and prediction
SC: Seismology [S]
MN: 2004 AGU Fall Meeting