Grain size analyses were performed following standard procedures at the US Geological Survey's Pacific Coastal and Marine Science Center in Menlo Park, CA. Size distributions of the mud and sand fractions were analyzed separately using a Beckman Coulter LS100Q and the gravel fraction by wet sieves. Statistics were calculated using the method of moments within the USGS' pcSDSZ program. Total carbon (TC), total inorganic carbon (TIC), and Total organic carbon (TOC) values represent percent dry weight.