d. installation of instruments and equipment on amphibious 

 vehicles; 



e. perfection of field survey techniques to meet project 

 requirements and environmental conditions; and 



f . the full use of a precise and accurate navigation system. 



Secondary objectives for this test were to gather scientific data and 

 determine the quantity and activity level of tagged sand necessary for 

 tracing activities. 



The site selected for this phase of the study was near Surf, Cali- 

 fornia. Location of this site, in relation to those sites studied at 

 Point Conception, is shown in Figure Ik . This site near Surf is a long 

 straight beach on the Vandenberg Air Force Base property (Figure 15). 

 The beach trends approximately 15° NE - 195° SW; landward is a row of 

 dunes. Behind the dunes are a marsh and lake which constitute a part of 

 the mouth and flood plain of the Santa Ynez River . While the Santa Ynez 

 River is normally blocked from draining into the Pacific Ocean, it 

 occasionally cuts through the dunes to the ocean following heavy rains 

 as shown in Figure 15. 



To the north of Surf, the Upper Monterey Formation outcrops along 

 the shore and forms a rocky beach area with associated kelp in the vicin- 

 ity of Purisima Point (Figure l6). Consisting of hard, laminated, silic- 

 eous shale, cherty shale, and diatomite, the Upper Monterey Formation is 

 also highly jointed; large blocks of the formation are strewn about on 

 the ocean bottom in the vicinity of the promontory. 



At Surf, the beach contours tend to follow the coastline irregularly 

 (Figure IT). The bottom consists mostly of fine and medium sand with a 

 few rocky areas. Profiles in the survey area at Surf have a bottom slope 

 (a) of approximately 0.01 (see Figures 18 through 20). 



The beach and nearshore sediments at Surf, California, are fine to 

 medium grained, light brownish gray (2.5Y6/2 Munsell color code) quartz 

 sand. Medium grained (l<f)-2<j>) sand occurs on the beach and offshore to 

 depths of 6 to 12 feet. Fine (2<}>-3<t>) sands occur from the 12-foot depth 

 to the limits of the survey (50 feet). Along a given range, sand size 

 decreases progressively seaward. Also the average particle size for a 

 range (average of samples from MLLW to -50 feet) tends to increase south- 

 ward from 2.3<J> (.203 mm) at range 157 to 1.9$ (.26 mm) at range 170. 

 Detailed granulometric analyses are given in Appendix E. 



Composition of the sand is 70 to 80 percent subangular quartz grains 

 (roundness 0.H, sphericity 0.8) with the remainder composed of metamorphics, 

 heavy minerals, and small amounts of shell material. The opaque heavy 

 minerals are smaller and more well-rounded than other material. Echinoid 

 (sand dollar) fragments are plentiful at the 30-foot depth, particularly 

 on Ranges 157, 160-165, and 167 but are rare at other depths. The 2|+-foot 

 depth sample on Range 155 is composed almost entirely of echinoid spines. 



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