The collection and analysis of sediments from Santa Monica Bay adds to the information concerning the continental shelves in that this bay represents a different environment from those previously investigated. The narrow shelf cut by the two submarine canyons, the sources of material from the flood waters which come out of the Santa Monica Mountains, and the good development of currents coming from the northwest make up these environmental influences.

The sediments of this shelf were found to show no particular outward decrease in grain size. Both coarse materials and rocky bottom were found near the outer margin as well as near shore. Evidence of periodic changes in the sediment character was found. It seems highly probable that the shelf is essentially a wave-cut terrace, that much of its sediment is residue from times of lower sea-level during the glacial stages, and that much of the modern sediment is of transitional character. There are some indications that oil may be accumulating in the finer sediments of the bay.