A Descriptive Analysis of the Morphology and Movement of the Golden Gate Sand Waves

High-resolution bathymetric surveys are interpreted to describe the morphology and movement of a field of sand waves near San Francisco, CA, USA. The sand wave size, shape, orientation, and migration are described. Portions of the field are nearly two dimensional, but the overall field is three dimensional, with changes in sand wave size, orientation, and structure. The trough-to-crest height of individual sand waves ranges from 2 to 9 m. There are a range of wavelengths and orientations. The dominant wavelength ranges from 90 to 100 m, and the orientation clusters around two directions: 40 and 68 degrees. The field is found to be highly dynamic but with stable characteristics over at least decadal timescales. A previously demonstrated paradox between sand wave shape asymmetry and migration direction is revisited using new measurements, showing that reversals in shape asymmetry were accompanied by changes in crest migration direction in one of seven surveys.