158 



topography and sediment size indicating that organic particles 

 are selectively transported from nearshore and the topographic 

 highs and deposited in deeper water in the same manner as 

 detrital sediments. The high values near the Hyperion outfall 

 indicate that here there is a faster rate of deposition of 

 organic matter than can be oxidized, removed, or masked by 

 detrital sediment. 



Cores and borings, especially those close to shore, show 

 extreme vertical variations in texture. These variations may 

 be due to many factors, including (1) fluctuations in quantity 

 of sediment reaching the bay from the watersheds and other 

 sources, (2) redistribution during periods of especially 

 strong turbulence in the bay or in periods of calms, (3) the 

 deposits may be related to former positions of sea level, 

 (4) formation of special topographic features or changes in 

 bottom topography, such as offshore bars, which may allow the 

 accumulation of unique deposits, and (5) slumping of sediments, 



It is likely that many of the textural changes in the 

 cores from the submarine canyons are the result of slumping. 



The clays and vegetation found in cores nearshore and 

 also in borings made on land close to shore are believed to 

 be due to deposition behind offshore bars. Landward migration 

 of sand from these bars may be the source of the sand in the 

 El Segundo Sand Hills, 



