El Tigre Fault

[5] The Andes Mountain belt trends with respect to the Nazca Plate/South American Plate convergence zone, and deformation is divided between the Precordilleran thrust faults and the El Tigre strike-slip motion.

[6] Morphology of El Tigre strike-slip fault is visible on the western slope of the Precordillera fold and thrust belt.

[3] Slip rate is estimated to be approximately 1 mm/year[3] and offsets range from 60 to 180 m.[5] The Nazca/South American oblique convergence zone off Chile is N76° [5] and El Tigre releases the north-south stress component of continental plate motion[6] at about 30°-31°.

[1][2] Sag ponds (releasing basins) form when the right lateral fault bends to the left causing the crust to extend (transtensive).

[1][2] The scarp has a slope of 18-24° and maximum height of 85 m.[2] Tectonic shortening appears to have changed direction from WSW-ENE to W-E during the Pleistocene, altering the kinematics to the present transpressive/transtensive system from a mainly transcurrent one.

[2] The termination point for El Tigre in the south is recognized by a merging within the Precordilleran Paleozoic strata, as well as its extremely disturbed surface deformation.

[1][2] The faults location in a seismically active zone and a low erosional environment makes it a good study area.

[2][5] The kinematics, geometry, extension, and deformation have not been widely agreed upon,[2] therefore the new interest in the El Tigre Fault should lead to further studies using modern technology.