The Southern NPRA electromagnetic and magnetic airborne geophysical survey is located in northwest Alaska in the southern National Petroleum Reserve-Alaska, about 320 kilometers south of City of Utqiagvik. Frequency domain electromagnetic and magnetic data were collected with the DIGHEMV system from July to August 2005. A total of 11,115 line kilometers were collected covering 3,947.9 square kilometers. Line spacing was 400 meters (m) and 200 m over the Drenchwater area. Data were collected with an average ground clearance of 35 m from a helicopter towed sensor platform ("bird") on a 30-m-long line.
