Helicopter-borne Electromagnetics (HEM) Area 196 Gnarrenburg

BGR conducted an airborne survey in the region of Gnarrenburg (Lower Saxony) as part of the BGR project D-AERO-Moore. This project is a study to survey the mires near Gnarrenburg with the BGR airborne geophysical standard measuring system. The peatland is located about 30 km northeast of the city of Bremen between Bremervörde and Worpswede . The size of the area is about 173 km². The area was surveyed with 6 flights totalling to 778 line-km (206,972 survey points). The nominal separation of the 62 WNW-ESE lines and 6 NNE-SSW tie lines was 300 m and 1500 m, respectively. In addition, 33 NNO-SSW lines at 100 m line separation were flown. The maps display the geophysical parameters apparent resistivity, apparent depth and centroid depth derived from the HEM data at the six frequencies of the HEM system (0.4 - 130 kHz). Furthermore, vertical slices were derived from layered-earth models (resistivities and thicknesses of six or twenty model layers) for each flightline and also, based on twenty-layer models, ten horizontal slices at 1 - 80 m depth.