This 100-m-resolution sediment thickness data raster for the Offshore of Arcata, California, map area is part of USGS Data Series 781 (Golden and Cochrane, 2019). Seismic data were collected by the USGS in 2009 using a mini-sparker seismic systems installed on the Humboldt State University R/V Coral Sea. The data were processed by the USGS into segy format files. The data are available as a georeferenced TIFF image.