Underwater location

As wc go into the next century, because of an apparent glut of petroleum on world markets and because of much greater optimism pertaining to the ultimate natural gas reserves in the world, the emphasis on the exploration for petroleum and natural gas in underwater locations has markedly diminished. 

The tracer pipeline leak testing, which is similar to the tracer tank leak testing, is effective for locating leaks in all types of pipeline installations, including pipe buried under pavement, airline runways, buildings, or underwater. Where leaks are known to exist, the tracer leak test is effective in determining their location without expensive excavation. 

These obviously include UXO,1 IEDs,2 and other ERW,3 but also may include similar objects underwater, buried in the seabed. There are also abandoned mining and construction sites that may need to be searched for old explosives. No matter which type object we may hypothesize as the source of molecules found, we need to follow similar reasoning to locate that source. 

Dock, M., M. Fisher, and C. Cumming. Novel detection apparatus for locating underwater unexploded ordnance, in Proceedings of the 5th International Symposium on Technology and the Mine Problem, Mine Warfare Association, Monterrey, California, April 2002. 

The underwater measurements were made using the following technique expl chges were detonated at a depth of ca 25 ft in water ca 45 ft deep. Piezoelectric pressure gages were located at the 25 ft depth at distance of 25 and 50 ft from the chge (Fig. Ex 17). The location of the chges and the gages were chosen in the manner not to have reflections from the... 

The top right of Figure 1.22 shows the tidal turbine that can be used in many tidal areas. They are basically wind turbines that can be located anywhere there is strong tidal flow. They are arrayed underwater in rows, as in some wind farms. The turbines function best where coastal currents run between 3.6 and 4.9 knots (4 and 5.5 mph). In currents of that speed, a 15-meter (49.2-feet) diameter tidal turbine can generate as much energy as a 60-meter (197-feet) diameter wind turbine. Ideal locations for tidal turbine farms are close to shore in water depths of 20-30 meters (65.5-98.5 feet). 

The Crimean shelf extends from Cape Khersones in the west to Cape Meganom in the east. It is widest off Cape Sarych (35-40 km) and narrowest off Cape Ayu Dag (5 km) [1,2]. This region is subjected to intensive wave action because it is exposed to all the southerly winds. The boundary of the underwater coastal slope is located at depths of 30-40 m. The near-shore zone is the area of alongshore sediment transport and smoothing of the bottom topography. Underwater and dried abrasive remnants are common the largest of them are confined to the capes composed of strong volcanic rocks [7,8]. 

A tank pit for housing waste collection equipment and process and storage tanks is located behind and below each cell cubicle and shielded from it by a concrete wall. The equipment in the tank pits is serviced and maintained by means of a combination of contact, remote, and underwater maintenance techniques. 

Figure 3. Cross section of Kooken Cave and overlying land surface. No vertical exaggeration. Lower portions of cave, with white tone and no black line, are unmapped, because they are underwater. The cave extends to unknown depth. General position of sample locations is indicated by number. Dashed lines show cave passages that are behind others. Modified from a map by Bryan Crowell.

At great ocean depths or in areas with poor visibility other devices may be employed. Sonar may be used to determine the location of large or encrusted objects by calculating the time it takes echoes to bounce off them. Underwater cameras may be towed by the boat to take pictures of a site in water with good visibility. 

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