2002/05/01 by Thomas L. Pratt, John H. Shaw, James F. Dolan +4 · 37 citations
Earth and Planetary Sciences · #earthquake and tectonic studies #Seismic Waves and Analysis #Seismic Imaging and Inversion Techniques #Geology #Fault scarp #Seismology #Fold (higher-order function) #Echelon formation #Thrust fault #Fault (geology) #Active fault #Slip (aerodynamics) #Thrust #Structural basin #Geomorphology
paper · doi:10.1029/2001gl014313
published in Geophysical Research Letters 29(9) (American Geophysical Union)
openalex publication_date 2002/05/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
High‐resolution seismic reflection profiles image discrete folds in the shallow subsurface (<600 m) above two segments of the Puente Hills blind‐thrust fault system, Los Angeles basin, California. The profiles demonstrate late Quaternary activity at the fault tip, precisely locate the axial surfaces of folds within the upper 100 m, and constrain the geometry and kinematics of recent folding. The Santa Fe Springs segment of the Puente Hills fault zone shows an upward‐narrowing kink band with an active anticlinal axial surface, consistent with fault‐bend folding above an active thrust ramp. The Coyote Hills segment shows an active synclinal axial surface that coincides with the base of a 9‐m‐high scarp, consistent with tip‐line folding or the presence of a backthrust. The seismic profiles pinpoint targets for future geologic work to constrain slip rates and ages of past events on this important fault system.