486 



SHEPARD 



[CHAP. 20 



Scripps Institution aqiialungers found the sand moving along the axis untiJ it 

 fell over a cliff as a sandfall (Fig. 5). Tracing the main canyon outward (Fig. 6) 

 it continues for 20 miles as a winding steejD-walled V-shaped gorge and termi- 



SAN LUCAS CANYON 



SOUTHERN BAJA 

 CALIFORNIA 



SAN 



CRISTOBAL PT 



CABO FALSO 



NAUTICAL MILES 



0£PT»S IN FATHOMS 



Fig. 6. The deeply dissected slopes south of Cape San Lucas. The two canyons are cvit in 

 granite and both terminate at about 1325 fm. Contour interval 50 fm, with 25 fm 

 added at top and bottom. (From Scripps Institution P.D.R. surveys.) 



nates in an irregular fan at a depth of 1325 fm (2420 m). The canyon walls are 

 granite or another type of resistant rock. The canyon floor contains only sand, 

 and the sand continues at least out onto the head of the fan. Unlike the end of 



