An approach to the reconstruction of deformed continental crust using gridded geophysical data

Abstract

We present a method to reconstruct crustal deformation in a continental regime using digital potential field data. The technique requires a continuous strain map estimated from available geological and geophysical data. Using this strain pattern, paleo-latitudes and paleo-longitudes are mapped as a function of their present-day geographic coordinates. These data, in turn, may be used to transform any digital data from the same region to an undeformed state. The method can incorporate non-uniformly distributed strain and is demonstrated by reconstructing a simple lineament map of the Matachewan dyke swarm as well as a gridded aeromagnetic data set. Data are from the central Superior Province of the Canadian Shield and reveal deformation associated with the Kapuskasing structural zone. Reconstructed field data display the three subswarms of linear Matachewan dykes radiating from a broad focal region. Once restored, data sets such as these may be used to examine the continuity of other geologic features, refine estimates of deformation, and identify other possible tectonic events.