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Christopher M. Castillo

Publications and source records attributed to Christopher M. Castillo.

2 recordsLinked to original sources

Colored shaded-relief bathymetry, acoustic backscatter, and selected perspective views of the northern part of the California Continental Borderland, southern California

The California Continental Borderland is the complex continental margin in southern California that extends from Point Conception southward into northern Baja California (Fisher and others, 2009). This colored shaded-relief bathymetry map of the northern continental borderland in southern California was generated primarily from multibeam-echosounder data collected by the University of Washington in 2016, the Ocean Exploration Trust-Nautilus Exploration Program in 2015–17, and the National Oceanic and Atmospheric Administration in 2017. These datasets were processed in part by the U.S. Geological Survey. Additional smaller amounts of publicly available multibeam-bathymetry data collected by other federal and local agencies, academic institutions, and private firms were also incorporated into this map. Since the production of this map, other multibeam-bathymetry data have been collected in this region.

California

Coexisting seismic behavior of transform faults revealed by high-resolution bathymetry

Transform faults are known to have anomalously low rates of seismicity, but no direct observations reveal why this is the case. We use new, autonomous underwater vehicle high-resolution seafloor mapping to image the morphology of and offsets along transform fault segments in the Gulf of California. Fault splays display a varied history of activation and deactivation of individual fault strands over time, not unlike those mapped onshore or imaged within the bathymetry of the Queen Charlotte-Fairweather and the Palos Verdes faults of offshore western Canada and Southern California. A series of six identically offset depositional fans evidence 21–23 meters of slip along the main transform fault, which could not have been produced by a single earthquake. Rather, the lack of smaller-magnitude offsets indicates synchronous deposition and an absence of multiple slope failure-inducing earthquakes, thus providing the first direct evidence that creep and earthquakes occur at different times in the slip history of a given transform fault segment.

Geology