The Sudbury Structure was
emplaced 1850 Ma ago and consists of three major components: the Sudbury
Basin (yellow), the Sudbury Igneous Complex (purple) which surrounds the
Basin and an outer zone of shatter-coned and intensely brecciated footwall
rocks.
In plan view, the Sudbury Igneous Complex has an elliptical
shape with a northeast-trending long axis of 60 km and a short axis of 27 km.
The elliptical shape is the result of northwest-trending compression during the
1.8 Ga Penokean orogeny. Its three-dimensional shape is not well known; it has
been considered a sheet-like loccolith, a ring dyke, a lopolith and a funnel
shaped complex.
Deducing the original three dimensional shape of the Sudbury
Structure is one of the many aims of the
Canadian
LITHOPROBE Project. An important component of the project is the application
of high-resolution seismic studies to the understanding of deep crustal
structure in mining camps.
