Identifying structural trend with fractal dimension and topography

Abstract

A digital elevation model (DEM), derived from light imaging detection and ranging (LiDAR) altimetry data, is used to investigate the fractal characteristics and structural trends of a topographic surface. The study area is located on the southeastern rim of the Sudbury Basin, a meteorite impact feature in Ontario, Canada. Visual interpretation and statistical analysis of fractal dimension (D) indicate that the geological units in the study area are characterized by statistically different distributions of D. In addition, the landscape exhibits two predominant aspect directions: 127° and 290° or ∼SE and NW. High values of D correspond to these predominant aspect directions. Topographic ridgelines exhibit a NE-SW trend, which is perpendicular to that of the highest fractal dimensions and the predominant aspect directions. It is suggested that these ridgelines are topographic expressions of tectonic fabrics present in the various geological units. Genesis of the tectonic fabric is related to the NW-SE–directed shortening of the Sudbury Basin impact crater.