TOWARDS AN UNDERSTANDING OF LONG-TERM STRESS RELEASE RATES ALONG THE NORTH ANATOLIAN FAULT,TURKEY
KOZACI, O., Department of Earth Sciences, University of Southern California, Los Angeles, CA 90089, email@example.com; DOLAN, J., Department of Earth Sciences, University of Southern California, Los Angeles, CA 90089, firstname.lastname@example.org; FINKEL, R., Center for Acclerator Mass Spectrometry, Lawrence Livermore National Lab., Livermore, CA 94551, email@example.com
The manner in which major plate-boundary-scale faults store and release stress over different temporal and spatial scales remains an unresolved problem in Earth Science. Paleoseismology, space geodesy and paleomagnetism have provided valuable information about slip rates over 10-103 years and 105-106 years respectively. It is important, however, to extend this record throughout the Holocene in order to be able to understand the behavior of major faults over multiple earthquake cycles. To this end, we are using cosmogenic nuclide techniques (10Be and 36Cl) to date offset fluvial terraces and fans along the North Anatolian fault in Turkey. Our study sites are situated on the central and eastern sections of the NAF, with offsets ranging between 30 and 200 meters, covering a time interval of ~1 to 10 ka. The slip rates we have generated thus far indicate that strain release along the NAF has been relatively constant during the Holocene. Moreover, these intermediate-term strain release rates are generally similar to the short-term rate of elastic strain accumulation revealed by GPS geodesy (e.g., McClusky et al., 2000; Reilinger et al., 2006). We attribute these relatively constant loading and release rates to the relative structural simplicity of the Anatolia-Eurasia plate boundary in northern Turkey. In addition to our slip rate results, we will also present our preliminary results from our Lorut paleoseismologic site along the eastern part of the NAF near Erzincan.