APPLICATION OF GROUND PENETRATING RADAR TO ESTIMATE SAND AND GRAVEL RESOURCES NEAR BOW, SOUTHERN NEW HAMPSHIRE

This study was conducted to test the potential of GPR to map the distribution of high quality units in a fixed area. Sand and gravel deposits in southern New Hampshire are a remnant of thousands of years of surficial glacial geologic processes. These washed and sorted sands and gravels are of a high quality and have intrinsic properties that make them sought after by the construction industry. Unlike lower quality material the sands and gravels, are transported by truck and rail long distances for use in important infrastructure projects throughout the northeast. The resource is becoming increasingly scarce due to depletion, anthropologic sterilization, land use, and environmental concerns. The environmental and economic impact sand and gravel deposits have on the region underscores the need develop methodologies to accurately assess the resource. To that end, a ground penetrating radar survey was completed to map part of a shallow gravel deposit. The results show that the 250 MHz snake line-style ground penetrating radar survey had enough resolution and depth of exploration to penetrate 3 to 5 meters. These data were used to construct deposit top and bottom grids. The grids were then used to calculate the volume of gravel within a 10- by 10- by 5-meter block. In this case, the volume of material was estimated to be 263 m².