Method and apparatus for surveying hydrocarbon reserves

A system and method for performing a radiological survey to identify subterranean hydrocarbon reserves. In one embodiment, the system includes a vehicle which serves as a platform for a radiation detector and a position sensing system. The radiation detector takes continuous measurements of surface radiation as the vehicle traverses the survey area, thereby measuring an average of the radiation over a portion of the vehicle's path. As each radiation measurement is taken, corresponding position information is generated by the position sensing system and recorded. In one embodiment, the position sensing system comprises a global positioning system which produces coordinates corresponding to the radiation measurements. The data generated by the system can be used to produce radiological maps of the survey area. The data can also be used to calculate the volume of hydrocarbon reserves underlying the survey area. Generally speaking, low radiation levels indicate the presence of hydrocarbon reserves.