The Altyn Tagh fault (ATF) is one of the most important structures in the India-Eurasia collision and earth scientists often cite it when discussing the behavior of large strike-slip faults, however little is known about its earthquake geology and history. To address this irony, we documented the fault trace geometry, magnitude of surface offsets, and timing of recent earthquakes to reconstruct the earthquake history of the central ATF for the last ~3000 years. Our data indicate that the central ATF produces moderate to large earthquakes, but is presently not as active as either the San Andreas or North Anatolia faults. The results of this work address the current discrepancy between geologic (~30 mm/yr), and geodetic (~10 mm/yr) estimates of slip rate. This discrepancy may result from changes in long term loading rate (e.g., southward migration of deformation to structures such as the Kunlun fault).

The following pages are divided into three sections (geometry, geomorphic offsets, paleoseismology) and show the results of three years of study along the central Altyn Tagh fault by Zack Washburn (ECI), and J Ramón Arrowsmith.




Fault Trace Geometry

• Regional Tectonics
  
• Active Trace Map
  
• site maps
  
• CORONA photographs
  
• Pictures of the fault trace
  
• surveyed topographic maps
  

• photographs referenced to location
  
• topographic maps of offsets
• Offset distribution

• trench sites with topographic maps
  
• trench logs
  
• trenching photographs