Geology Reference
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60
Dextral Offset measurements
using HRS images
Repeve Strike-Slip Offsets
on the Fuyun Fault, China
50
40
30
20
10
0
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60
80
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120
Distance along the fault (km)
Fig. 6.19 Displacement of geomorphic markers along a strike-slip fault.
Plot of displaced markers versus distance along the Fuyun Fault in northern China. Along more than 100 km of fault
length, Quickbird imagery was used to identify and sequentially restore offset features in order to define multiple
slip events. Data gaps tend to occur near segment boundaries and changes in fault orientation that cause contractional
features near bends. Modified after Klinger et al. (2011).
Second, histograms of the magnitude of
displacement are constructed for all of the
displaced features along a fault. When the
reliability of each measurement can be assessed,
this somewhat subjective variable should be
cataloged as well. If a segment of a fault were
typified by repetitive ruptures of similar
magnitudes, then histograms of displacements
along that segment would tend to display
groupings of offsets that were multiples of
each  other. For example, repetitive offsets of
comparable amounts occur along much of the
Fuyun Fault in northern China (Figs 6.19 and
6.20) or along individual segments of the
Garlock Fault in California (McGill and Sieh,
1991). Along much of the Fuyun Fault, similar
displacements occur in as many as five slip
events (Klinger et al. , 2011), thereby suggesting
a repetitive rupture pattern that would be typical
of faults dominated by characteristic earthquakes
(Schwartz and Coppersmith, 1984). In contrast,
along the Garlock Fault, displacements within
individual segments commonly appear repetitive
for a few events, but neighboring segments
display differing slip-per-event histories. Such
contrasts have been interpreted to suggest that
rupture patterns may vary significantly from one
Characterisc Slip,
Fuyun Fault, China
n ~ e (-n/1.82)
Dextral offset (m)
Fig. 6.20 Histogram of strike-slip displacements
along the Fuyun Fault.
Compilation of displaced features along > 100 km of the
Fuyun Fault (data in Fig. 6.19). The most recent rupture
averaged 6 m of displacement and corresponds to the
1931 M s = 7.9 earthquake. Previous ruptures cluster
near multiples of 6 m, and are interpreted to indicate
that the Fuyun Fault hosts characteristic earthquakes.
Geomorphic degradation appears to cause an
exponential decrease in the preservation of offsets as a
function of time. Modified after Klinger et al. (2011).
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