Proceedings of the 12th International INQUA meeting on paleoseismology, active tectonic and archaeoseismology

266 1 2 T H I N T E R N AT I O N A L I N Q U A M E E T I N G O N PA L E O S E I S M O L O G Y , A C T I V E T E C T O N I C S A N D A R C H A E O S E I S M O L O G Y ( PATA ) , O C T O B E R 6 T H - 1 1 T H , 2 0 2 4 , L O S A N D E S , C H I L E PATA Days 2024 K E Y W O R D S Slip rate, tectonic geomorphology, extension, surface faulting, geochronology (1) Nevada Bureau of Mines and Geology, University of Nevada, Reno, USA. rkoehler@unr.edu (2) Department of Geology, University of Otago, Dunedin, New Zealand. Mark. *Email: stirling@otago.ac.nz Rich D. Koehler (1) Mark Stirling (2) PALEOSEISMIC CHARACTERIZATION OF THE BUFFALO VALLEY FAULT, CENTRAL BASIN AND RANGE, NEVADA, USA A B S T R A C T The Buffalo Valley fault is an active range front normal fault that accommodates extension within the slowly deforming Basin and Range Province in central Nevada, USA. Field and lidar observations indicate that deformation is distributed across several parallel strands that progressively displace alluvial fans. Here we present fault trace mapping, vertical displacement estimates, and soil pit descriptions from displaced surfaces. Cumulative displacement across the oldest surface is ~21 m and late Pleistocene surfaces are displaced 6.3 m. Soils developed into late Pleistocene surfaces have stage II+ to III carbonate development suggesting an age for surface abandonment ~100-200 ka. 36Cl soil depth profile analyses are in progress and will refine the age of these surfaces. The data suggests a broadly constrained slip rate of 0.03-0.06 mm/yr. The results contribute towards the refinement of seismic hazard models and the assessment of geothermal systems in the region. I N T R O D U C T I O N The Buffalo Valley fault in the central Basin and Range Province, Nevada USA is an active east-dipping normal fault that extends for ~38 km along the east side of the Tobin Range (Fig. 1). The Tobin Range represents a horst structure bound on its west side by the Pleasant Valley fault zone, the source of the 1915 M7.6 earthquake. Although the Buffalo Valley fault has not generated a historic earthquake, long-term tectonic activity is evidenced by prominent