GROUND PENETRATING RADAR: A GEOPHYSICAL TOOL TO SEARCH FOR WATER ON MARS
Eyuboglu, Abbas S. and Haydar J. Al-Shukri, University of Arkansas at Little Rock, 2801 South University Avenue, Little Rock, AR 72204
Surface geophysical methods are non-invasive tools used to characterize the subsurface. Probably the most important task of any geophysical investigation will be characterizing the natural geologic and hydrogeologic conditions. Many geophysical techniques have been suggested as candidates for water sounding on Mars, including ground penetrating radar (GPR), active seismic, electric, and electromagnetic. Ground penetrating radar is a reflection technique, which uses high frequency electromagnetic waves to acquire subsurface information. GPR responds to changes in electrical properties, which are a function of soil and rock material and moisture content. A series of laboratory experiments were conducted to validate the effectiveness of the GPR technology in resolving anomalous characteristics of various combinations of ice, liquid water, dry soil, and fully saturated soil. A carefully designed laboratory model was constructed from wood such that minimum amount of metals (nails, screws, etc) are used. This was needed to prevent metal interference with radar signal and the contamination of studied anomalies. Fresh (tap) water and metal-free sand were used in the soil simulation. Due to the model size limitation, laboratory data was collected using the 1.5GHz antenna. Many combinations of ice, water-saturated sand, and dry sand where studied, however, they all concentrated on analyzing the signature of liquid water on the radar data. Results obtained so far indicate that GPR technology has very high potential of becoming the tool for groundwater prospecting on Mars.