Near-Field Deformation from the El Mayor-Cucapah Earthquake Revealed by Differential LIDAR

Large [moment magnitude (M-w) >= 7] continental earthquakes often generate complex, multifault ruptures linked by enigmatic zones of distributed deformation. Here, we report the collection and results of a high-resolution (>= nine returns per square meter) airborne light detection and ranging (LIDAR) topographic survey of the 2010 M-w 7.2 El Mayor-Cucapah earthquake that produced a 120-kilometer-long multifault rupture through northernmost Baja California, Mexico. This differential LIDAR survey completely captures an earthquake surface rupture in a sparsely vegetated region with pre-earthquake lower-resolution (5-meter-pixel) LIDAR data. The postevent survey reveals numerous surface ruptures, including previously undocumented blind faults within thick sediments of the Colorado River delta. Differential elevation changes show distributed, kilometer-scale bending strains as large as similar to 10(3) microstrains in response to slip along discontinuous faults cutting crystalline bedrock of the Sierra Cucapah.