MODELING COMPLEXLY MAGNETIZED 2-DIMENSIONAL BODIES OF ARBITRARY SHAPE

A method has been devised for the forward computation of magnetic anom alies due to two-dimensional (2-D) polygonal bodies with heterogeneous ly directed magnetization. The calculations are based on the equivalen t line source approach wherein the source is subdivided into discrete elements that vary spatially in their magnetic properties. This equiva lent dipole line method provides a fast and convenient means of repres enting and computing magnetic anomalies for bodies possessing complexl y varying magnitude and direction of magnetization. The algorithm has been tested and applied to several generalized cases to verify the acc uracy of the computation. The technique has also been used to model ob served aeromagnetic anomalies associated with the structurally deforme d, remanently magnetized Keweenawan volcanic rocks in eastern Lake Sup erior. This method is also easily adapted to the calculation of anomal ies due to two and one-half-dimensional (2.5-D) and three-dimensional (3-D) heterogeneously magnetized sources.