54 



where aP = dP (record mean) - dP (horizontal) and ax = gage 

 length of arm. The specific gravity of the fluid back-filling the 

 sensor diaphragms, 

 /., must be dif- 

 ferent than that of 

 the surrounding sea- 

 water, /. If both 

 differential trans- 

 ducers along an axis 

 are operating cor- 

 rectly, the angle of 

 tilt calculated for 

 colinear arms should 

 agree with opposite 



signs. The direction FIGURE IV-3: Instrument tilt above the sea- 

 floor, 

 of tilt is defined 



after considering 



the manner in which the differential pressures are reported by the 



instrument, (i.e., dP = P (arm) -P (center) ) . An increase in the mean 



value of a differential transducer indicates that the end of the 



corresponding arm is slanting upwards (neglecting any changes in 



temperature) . 



V 







. 





— — 



r— 



^-^ cx^ 



XN^ 







^^^J-^ 



^^^^s:" 



-- ° 1 





^0+^ 











V 



