SR1703 Knudsen sub-bottom profiler data

This folder contains single-channel subbottom profiling data (CHIRP) collected offshore of Southern California between San Diego and Dana Point focused on the San Diego Trough fault aboard the R/V Sally Ride in February 2017. Contents: processed segy data, navigation files (WGS-84), line plots The primary chirp survey for this project was conducted during a coring shake-down cruise on the R/V Sally Ride under Captain Ian Lawrence between February 3-11th, 2017. Chief Scientist Mitch Lyle graciously allowed us to run seismic profiles overnight between coring operations. The surveys were conducted by Hector Perea and Neal Driscoll (SIO), with Bormann (UNR/CSULB) remotely planning and monitoring data collection from shore. This survey resulted in 32 new profiles totaling 280 line-km of ultrahigh-resolution sub-bottom profiles (Figure 2 - magenta grid). The data were acquired using the hull-mounted Knudsen Chirp 3260 Echosounder operated at 3.5 khz. The survey speed ranged between 4.0-5.5 knots with a 3-second shot interval. The reflected waveforms were sampled at 0.06 ms intervals for a 0.267-second window that auto-tracked the seafloor. The signal penetrated between 0.6-1 seconds of two-way-travel-time beneath the seafloor, imaging reflectors in the upper 45-70 m of sediment (all sub-bottom depths and stratal thicknesses estimated assuming a sound velocity of 1500 m/s).