Abstrakt
Gravity aspects data provided a new view into the near surface density character under the Tunguska surface. While gravity gradients show homogeneous pattern the second derivate of the gravity potential reveals denser character of the upper surface substrate east-east-south from the epicenter.
Symmetrically with the wings of the collapsed forest the denser substrate was detected north and south from the epicenter but not inside the epicenter. There the Tzz gravity aspects showed an area of lower density.
Regional magnetic data showed an area of reduced magnetic anomaly over the area of collapsed forest. The character of this reduced magnetic signature has parabolic shape with axis in the south-east-east (SSE) to north-west-west (NWW) direction.
Detailed magnetic mapping over the epicenter revealed magnetic structures oriented in SSE-NWW direction.