67 lines
3.1 KiB
Plaintext
67 lines
3.1 KiB
Plaintext
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(word processor parameters LM=8, RM=78, TM=2, BM=2)
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Taken from KeelyNet BBS (214) 324-3501
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Sponsored by Vangard Sciences
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PO BOX 1031
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Mesquite, TX 75150
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August 2, 1990
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Courtesy of NASA BBS at 205 895-0028
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SOIL SURVEYS
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Accurate soil surveys are necessary for soil conservation
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measures, determining building sites, selecting park locations,
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siting sewage plants and a variety of other reasons.
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The traditional method of surveying requires auger boring into the
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ground to obtain subsurface soil samples for classification, a slow
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and fatiguing process since a typical survey might require hundreds
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of depth measurements.
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The U.S. Department of Agriculture's Soil Conservation Service
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(SCS) is now employing an easier and faster method, developed in
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cooperation with NASA, that involves use of ground penetrating radar
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to produce subsurface graphs for interpretation by soil scientists.
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The radar antenna is pulled by a four-wheel-drive vehicle along a
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transect line, a straight line across the surface where normally
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many borings would be made.
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As it moves along the transect line at about five miles per hour,
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the antenna transmits radio waves downward that are reflected back
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to the antenna when they strike layers--soil, rock, water, man-made
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objects--of different electromagnetic properties.
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The antenna relays the reflected pulses to a graphic recorder
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mounted in the vehicle. The system analyzes the data and produces
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images on the recorder of subsurface "interfaces", areas where two
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different types of features meet.
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Soil scientists examine the recorder's printout. The information
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does not entirely eliminate the need to dig holes, but only a few
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are required to double-check the radar's findings.
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The radar can penetrate to depths of seven to eight feet
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routinely; in some types of soil it can reach 30 feet or more.
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--------------------------------------------------------------------
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If you have comments or other information relating to such topics as
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this paper covers, please upload to KeelyNet or send to the Vangard
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Sciences address as listed on the first page. Thank you for your
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consideration, interest and support.
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Jerry W. Decker.........Ron Barker...........Chuck Henderson
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Vangard Sciences/KeelyNet
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--------------------------------------------------------------------
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If we can be of service, you may contact
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Jerry at (214) 324-8741 or Ron at (214) 484-3189
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--------------------------------------------------------------------
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