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reservoirs and the date of their construction; all are in the 

 Malibu Creek watershed: Rindge Reservoir (1925); Craggs Lake 

 (1913); Malibu Lake (1923); Lake Eleanor (1881); Lake Sherwood 

 (1904). 



Other questions arising when calculating the rate of sedi- 

 mentation in Santa Monica Bay (specifically the shelf) are the 

 following? (1) How far are the sediments transported before 

 they are deposited? (2) Are the coarse sediments deposited 

 close to shore and most of the fine material carried great 

 distances, i.e., beyond the shelf, before being deposited? 

 (3) How much sediment is carried seaward along the floor of 

 the submarine canyons, especially Redcndo Canyon? (4) How much 

 sediment is deposited along steep slopes or at the head of the 

 canyons and later slumps into deeper water? (5) What volume 

 of sediments is winnowed from the shelf and carried beyond the 

 shelf before being redeposited? (6) What effect do animals 

 have on breaking down sediments thereby producing finer material 

 that may be winnowed away? 



Theoretically there should be an even gradation from coarse 

 to fine sediments in a seaward direction. In general, this 

 theory applies to Santa Monica Bay although there are several 

 parts of the bay that appear anomalous. Some of the abnormal 

 regions are due to quiet water close to shore (Redondo Canyon) 

 which allows the accumulation of fine detritus. One of the 

 major causes of the peculiar sediment distribution undoubtedly 

 results from the superposition of present day sedimentation 

 on top of a surface formed largely in the geologic past. For 

 example, the rock and gravel area on the outer shelf is believed 

 to have formed in late Pleistocene or early Recent time. Thus, 



