Structural analysis and remote sensing of the East Range, Sudbury Impact Structure, Canada


The 1.85 Ga Sudbury Impact Structure, located in the Canadian Shield of Ontario, was geometrically modified by orogenic deformation involving large-scale thrusting and non-cylindrical folding. Knowledge of the effects of this post-impact deformation is paramount for assessing the structural evolution of the synformal Sudbury Igneous Complex (SIC), the solidified impact melt sheet of the impact structure. Unravelling the geometry of the SIC, in particular its eastern portion, the East Range, is one of the prime targets of the planned deep drilling in the framework of ICDP. To date, neither impact nor orogenic models furnished plausible explanations as to the geometry of the basal contact of the SIC in the East Range, which hosts economically very important Cu-Ni sulphide and PGE-bearing mineral deposits. Preliminary results from the first phase of the project led to the working hypothesis that the East Range of the SIC constitutes a steeply westerly plunging antiform generated by brittle-ductile deformation, thus accounting for its conspicuous curvature at surface. Consequently, the state of brittle-ductile strain and kinematics of major fault zones in the East Range and adjacent lithologies will be assessed in the third phase of the project. This will be complemented by remote sensing analysis based chiefly on Shuttle Radar Topography Mission (SRTM) data, ETM satellite scenes and air photos as well as field structural analysis of brittle shear faults and determination of tangential unit shear vectors of prominent faults. Besides pertaining directly to the goals of the planned ICDP project at Sudbury, the project will contribute to unravelling orogenic deformation and to localizing massive sulphide and PGE deposits at Sudbury.


Projektleitung
Riller, Ulrich Prof. Dr. (Details) (Impaktgeologie (J))

Laufzeit
Projektstart: 02/2006
Projektende: 07/2007

Publikationen

Riller, U., 2005. Structural characteristics of the Sudbury Impact Structure, Canada: impact-induced and orogenic deformation. Meteoritics and Planetary Science, Vol. 40, p. 1723-1740.

Schwerdtner, W.M., Riller, U., and Borowik, A. 2005. Structural testing of tectonic hypotheses by field-based analysis of distributed tangential shear: concrete examples from major high-strain zones in the Grenville Province and other parts of the southern Canadian Shield. Canadian Journal of Earth Sciences, Vol. 42, 1905-1925.


Zuletzt aktualisiert 2020-09-03 um 17:05