Publication Date:
2016-03-12
Description:
Fault dips are usually measured from outcrops in the field or inferred through geodetic or seismological modelling. Here we apply the classic structural geology approach of calculating dip from a fault's 3D surface trace using recent, high-resolution topography. A test study applied to the 2010 El Mayor-Cucapah earthquake shows very good agreement between our results and those previously determined from field measurements. To obtain a reliable estimate, a fault segment ≥120-m-long with a topographic variation ≥15-m is suggested. We then applied this method to the 2013 Balochistan earthquake, getting dips similar to previous estimates. Our dip estimates show a switch from north to south dipping at the southern end of the main trace, which appears to be a response to local extension within a stepover. We suggest that this previously unidentified geometrical complexity may act as the endpoint of earthquake ruptures for the southern end of the Hoshab fault.
Print ISSN:
0094-8276
Electronic ISSN:
1944-8007
Topics:
Geosciences
,
Physics