Presentation: Radial magnetic inversion to retrieve the geometry of 3D sources
We present a method for inverting total-field anomaly data to estimate the geometry of a 3D geological source in the subsurface. The method assumes that both the magnetization vector and the depth to the top of the source are known. We use an ensemble of vertically juxtaposed 3D right prisms to approximate the shape of the geological source. Each prism has a known homogeneous magnetization and an unknown polygon as its horizontal cross-section. The vertices of the polygons approximate the horizontal depth slices of the source. The method estimates the horizontal coordinates of the vertices and the thickness of all prisms defining the interpretation model. The method is formulated in the space domain, as a constrained nonlinear inversion. Tests with synthetic and real total-field anomaly data show the efficiency of the method on retrieving the shape of the source and fitting the data.