to test capabilities of meeting military or quasi-military objectives, a 

 two-day program was conducted in the Point Sal area following the sand 

 tracing operations. 



In order to define the mechanics of littoral transport and trace 

 sediment movement around Point Conception, three survey areas were 

 selected: Area C north of Point Conception at Black Canyon; Area B 

 between Point Conception and Government Point, and Area A to the east of 

 Government Point at Co jo Anchorage (see Figure 27). At each site a point 

 injection was made in approximately 30 feet of water. It was judged that 

 by sequentially monitoring three sites it would be possible to integrate 

 the results and thus ascertain the track of sediment movement in the 

 vicinity of Point Conception. 



The areas around Point Conception (C, B, and A) are marked by sea 

 cliffs extending as high as 200 feet above a narrow beach. (See Figures 

 28 to 33-) North of Point Conception and east of Government Point, the 

 Sisquoc Formation is exposed along these cliffs. The Sisqu'oc Formation 

 consists of impure diatomite, diatomaceous shale, and pure laminated 

 diatomite. The Upper Monterey Formation, composed of hard laminated 

 platy siliceous shale, cherty shale, and diatomaceous lenses, outcrops 

 along the shore cliffs between Point Conception and Government Point. 

 At Areas A and C, the long narrow beaches at the base of the cliffs are 

 occasionally interrupted by ledges and other rock outcrops. Between 

 Point Conception and Government Point (Area B) are several pocket beaches. 



General orientation of the coastline changes from a north-south direc- 

 tion nt*bh of Point Conception to an east-west direction east of Government 

 Point, along the Santa Barbara Channel. The coastline trends are: Area C 

 approximately 353°N-173°S; Area B approximately 293°W-13 1 +°SE; and Area A 

 approximately 60°NE-2U0°SW (because of the bay configuration). Bathymetric 

 contours in these areas tend to follow the general coastline with no 

 prominent features (Figures 3^+ through 36). However, scuba divers in T 

 specting the bottom in Area B, found an abrupt ledge approximately 5 feet 

 high occurring at a depth of approximately 20 feet. Without a hoist or 

 winch, such a feature would stop entry to the beach by the towed detector 

 vehicle . 



The offshore bottom at Area C is generally sandy with scattered 

 boulders and outcrops. Immediately north and south of the area are ex- 

 tremely rocky areas with associated kelp beds. Nearshore at Area B, the 

 bottom is rocky with sand pockets; farther offshore fine sand becomes 

 more prevalent. The bottom at Area A is predominately sand with some 

 rock and kelp. Bathymetric profiles of these areas are shown in Figure 

 37. 



Sediments at the 30-foot depth near Area C consist of light brownish 

 gray (2.5Y6/2 Munsell color code), fine grained quartz sand. The sand is 

 composed of 85 x.o 90 percent subangular quartz grains (roundness O.k - 0.5, 

 sphericity 0.7). Metamorphics and heavy minerals with minor amounts of 



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