MAGNETIC MODELING AS A TOOL IN THE EVALUATION OF IMPACT STRUCTURES, WITH SPECIAL REFERENCE TO THE TVAREN BAY IMPACT CRATER, SE SWEDEN

Until recently computer modelling of radial-symmetric structures, like impact craters, has presented difficulties. As a result of this, such models are scarce in the literature. In this study, the magnetic stru cture of the marine Tvaren Bay impact crater (58 degrees 46'N, 17 degr ees 25'E) south of Stockholm is investigated with a sophisticated comm ercially available computer program developed for gravimetric and magn etic modelling of geological structures. Aeromagnetic data along three profiles across the crater have been used. It is concluded that the m ethod is an important supplement to other geological and geophysical i nvestigations in estimating the shape, depth and extension of the crat er and the surrounding region of basement that was fractured by the im pact.