A series of scans is generated for a subsurface and a derivative image is created using the series of subsurface images. One or more tests are performed on the derivative image, and a subsurface object is detected based on the one or more tests. A sensor is configured to generate a series of scans for a subsurface and a processor is coupled to the sensor. The processor is configured to execute stored program instructions that cause the processor to generate a series of images of the subsurface using the series of scans, create a derivative image using the series of subsurface images, perform one or more tests on the derivative image, and detect a subsurface object based on the one or more tests.