In Delaware some linear features recognized on the Landsat image can be related to known faults. Others are interpreted as possible faults; the causes of some lineations are not yet known. Circular features are more difficult to interpret but they are similar to the domal structures and erosional features recognized in the Gulf Coast region, for example. These and the linear features of uncertain origin can be investigated by drilling and geophysical techniques after being localized by clues provided by the satellite images. Detection by satellite images and confirmation by other geologic techniques is an efficient and effective means of geologic investigation.