Hybrid 1D/3D geologically constrained inversion of airborne TEM data

Abstract

TEM data are best interpreted in tight integration with geological data. A computer program, VPem1D, has been written to perform 1D TEM inversion in a 3D geological framework. The fact that VPem1D operates on a geological model facilitates a variety of inversion styles. For example, if one or more geological units are considered uniform in conductivity, the optimal conductivities can be determined for the entire survey area via homogeneous unit inversion. If geological units are variable in conductivity, heterogeneous unit inversion can be applied. Alternatively, because geological interfaces are captured in the model, geometry inversion can be used to adjust interfacial depths (e.g. depth to basement). VPem1D inversion is directly applicable to data from variety of systems including (but not limited to) GEOTEM, TEMPEST, VTEM, Spectrem, SkyTEM, MegaTEM and Hoistem. This paper will demonstrate the different inversion options as applied to a variety of case study data sets.