Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published December 2003 | Published
Journal Article Open

Paleoseismic Evidence of Characteristic Slip on the Western Segment of the North Anatolian Fault, Turkey

Abstract

We have conducted a paleoseismic investigation of serial fault rupture at one site along the 110-km rupture of the North Anatolian fault that produced the Mw 7.4 earthquake of 17 August 1999. The benefit of using a recent rupture to compare serial ruptures lies in the fact that the location, magnitude, and slip vector of the most recent event are all very well documented. We wished to determine whether or not the previous few ruptures of the fault were similar to the recent one. We chose a site at a step-over between two major strike-slip traces, where the principal fault is a normal fault. Our two excavations across the 1999 rupture reveal fluvial sands and gravels with two colluvial wedges related to previous earthquakes. Each wedge is about 0.8 m thick. Considering the processes of collapse and subsequent diffusion that are responsible for the formation of a colluvial wedge, we suggest that the two paleoscarps were similar in height to the 1999 scarp. This similarity supports the concept of characteristic slip, at least for this location along the fault. Accelerator mass spectrometry (AMS) radiocarbon dates of 16 charcoal samples are consistent with the interpretation that these two paleoscarps formed during large historical events in 1509 and 1719. If this is correct, the most recent three ruptures at the site have occurred at 210- and 280-year intervals.

Additional Information

© 2003 Seismological Society of America. Manuscript received 23 October 2001. The authors wish to thank the Ford Otosan for its support during this work. Some of the maps have been prepared using the Generic Mapping Tool free software. We thank R. Langridge and D. Ragona for their help during the field work. J. Liu, R. Armijo, and B. Meyer helped to improve this manuscript by their comments. We thank M. Meghraoui and an anonymous reviewer for very helpful reviews that significantly improved our analysis of the data. In memoriam of A. Barka, who died tragically while the article was in review. This is Caltech Contribution Number 8989 and IPGP Contribution Number 1936.

Attached Files

Published - 2317.full.pdf

Files

2317.full.pdf
Files (9.2 MB)
Name Size Download all
md5:28dd9b9a4430f7837ea78a8dc693cccc
9.2 MB Preview Download

Additional details

Created:
August 19, 2023
Modified:
October 26, 2023