readouts of load, displacement, and vertical orientation. These signals are 

 recorded on both a direct-writing oscillograph to allow innmediate monitoring 

 of the progress of a test and on magnetic tape for later reduction by the pro- 

 cess described in the Appendix. 



tether line 



acoustic projector 



hydraulic cylinder 



instrumentation 

 housing 



support pad 



wj^/mmm>^/,;^i^/s: m^ 



bearing plate 



load transducer 



Figure 1. Schematic of in-situ plate bearing device. 



TEST PROGRAM AND PROCEDURES 



The tests described in this report were performed during four 

 different sea cruises which were conducted during the development of the 

 plate bearing device. Testing was concentrated at two sites located off the 

 coast of Southern California in water depths of 1 ,1 75 and 6,000 feet. The 

 tests at the shallower site are designated Series 1 1 1 and those at the deeper 

 site are Series IV.* The geographic coordinates of the Series 1 1 1 site are 

 34°09.6'N, 119°45.3'W and the Series IV site are 33°52.rN, 120°35.9'W. 

 Figure 3 shows the location of these sites. 



Tests SC-1 through SC-12 were performed at the Series III site during 

 operations aboard the USNS Gear, ARS-34. These tests were conducted using 

 the rather primitive mechanical spring-linear potentiometer combination for 

 load measurement and a telemetry system which provided data from only one 

 sensor at a time. The result was inaccurate load data in the very soft sediment 



Test Series I and II were previously reported. 



