F-21 

 Canyon (Keller and Shepard, 1978). 



Although the first in situ submarine canyon measurements 

 were made in Lydonia and Gilbert Canyons (Stetson, 1937) , 

 most direct measurements have been made offshore from 

 California. Trumbull and McCamis (1967) , however, measured 

 a down-canyon velocity of 10 cm/sec in Oceanographer Canyon 

 using Alvin, and observed no sediment motion. Keller et al. 

 (1973) found comparable velocities of 8-15 cm/sec in Hudson 

 Canyon clearly displaying reversals of flow. Reversals have 

 also been described from Hydrographer, Wilmington, Washington, 

 and Norfolk Canyons (Shepard and Marshall, 1978; Keller and 

 Shepard, 1978). 



In order to investigate the relationships of sediment move- 

 ment and canyon faunas, we calculated bottom current velo- 

 cities for 17 of the camera sled transects investigated. The 

 current speed is measured from a Savonius rotor mounted 1.3 

 meters above the bottom of the sled ski. Current direction 

 is measured by magnetic compass with a resolution of 1.0 

 degree. The currents have been tabulated for each approxi- 

 mately 1/2 hour segment of on-bottom track. The current 

 vectors are shown as wind- rose diagrams in Figs. F-11-13 

 and by arrows on each of the three station maps. Figs. F-1, 

 F-3, and F-5, (the length of the arrow is proportional to the 

 current speed and its orientation shows the current direction. 



The measured currents have a mean velocity of 25 cm/sec. 

 In each of the three canyons they show a more or less normal 

 distribution centered around the mean velocity. The maximum 

 velocities are 50 cm/sec. The velocities greater than 40 



