Abstract: An underwater vibrator is specifically adapted for generating a shear wave in a seabed and includes a frame; locomotion apparatus attached to the frame for moving the vibrator over the seabed; and cable means connected between a surface support vessel and the vibrator. The vibrator also includes buoyancy and apparatus for selectively controlling the buoyancy along with apparatus for selectively engaging the seabed with the vibrator. Apparatus is also carried by the vibrator for viewing the location of the vibrator under the water which includes lights and television equipment.

Abstract: Apparatus for continuous shear wave logging of a borehole consisting of a sonde instrument having retractable, expandable coupling arms for rigidly engaging the borehole wall to exert repetitive torqueing action while continuously moving uphole. The sonde includes spaced detector coupling arms in continual contact with the borehole wall and polarized for detection of the repetitive propagated shear waves.

Abstract: Apparatus for detection and analysis of secondary uranium ores to provide signature indication of type by ultraviolet induced fluorescence and detection of fluorescence excitation time, peak value and decay time. The apparatus employs laser irradiation of selected terrain and telescopic detection at specific light wavelengths, viz. the yellow to green band; and thereafter detected signals are processed with specific circuitry to obtain and provide readout of the signature parameters.

Abstract: An air retaining skirt for use with an air cushion vehicle of a type which utilizes a peripheral series of loop and segment sections in combination to provide retention of the air cushion over uneven terrain or water. The loops are adapted to extend from the air cushion vehicle outward and downward in flexible, air inflatable composure, and each loop supports a plurality of ground-contacting segments affixed to the lower edge thereof and extending back up for retention at or near the lower edge of the air cushion vehicle.

Abstract: A control system for providing precise speed control for a rotary air modulator, and particularly for providing synchronized speed control as between two or more rotary air modulators. A common reference frequency is used for controlling rotational speed of one or more rotary air modulators wherein each modulator deploys an individual feedback system responsive to the reference frequency input to provide precise rotational speed and angular position coordination and, therefore, synchronism of frequency and phase output as between two or more individual modulators. The individual feedback systems include feedback and summation circuitry which derives angular velocity correction, angular position correction and hydraulic pressure drive variation for thereafter correcting and maintaining precise speed control of the rotary drive system.