Growth Faults and Relay Ramps: A High-Resolution Seismic Survey, Livingston Parish, Louisiana
Department of Geology and Geophysics, Louisiana State University, Baton Rouge, Louisiana
The United States Gulf of Mexico Coast is home to several east-west trending listric normal fault systems. One such system, the Baton Rouge–Tepetate Fault System, Louisiana, comprises a contemporaneous series of growth faults and relay ramps. There is evidence of recent movement in surficial fault line scarps, offset roads, and sedimentation patterns throughout the area. In order to study this soft sediment system, two near-surface (0 - 300 m), high-resolution (10 - 300 Hz), 300-m-long, continuous seismic reflection profiles (3 m geophone spacing; 24-channel) were collected across a growth fault and a portion of a relay ramp in Livingston Parish, Louisiana. The seismic source is a Down-hole Betsy Seisgun using 200 grains FFFF Black Powder and source-to-receiver offsets range from 4 m to 73 m. One seismic line crosses the tip of a growth fault. The other line crosses where the fault has a noticeable vertical offset. Through close evaluation of these data, correlated with well logs and gravity surveys across the fault and in the ramp area, this study proposes to investigate the link between (1) observed width and distribution of strain within the expected broad, fault deformation zone, and (2) sediment density distributions previously inferred from gravity studies.
AAPG Search and Discovery Article #90094 © 2009 AAPG Foundation Grants in Aid