Kanimblan Orogeny Kanimblan Orogeny The Kanimblan orogeny was a mountain-building event in eastern Australia toward the end of Early Carboniferous time (about 318 million years ago). It was a terminal orogenic episode forming the Lachlan Fold Belt, which was also known as the Lachlan Geosyncline before the advent of the plate tectonics theory. Uplift and deformation occurred in a 1,000 km belt extending from Tasmania to Cape York. However the original width was 2,000 to 3,000 km wide, with the excess size absorbed by folding and thrust faulting. The Kanimblan orogeny also affected the Tasman Geosyncline, which is aligned parallel with the
Andean orogeny and then to the opening of the Drake Passage 45 million years ago. The separation from Antarctica changed the tectonics of the Fuegian Andes into a transpressive regime with transform faults. About 15 million years ago in the Miocene the Chile Ridge begun to subduct beneath the southern tip of Patagonia (55° S). The point of subduction, the triple junction has gradually moved to the north and lies at present at 47° S. The subduction of the ridge has created a northward moving "window" or gap in the asthenosphere beneath South America. Andean orogeny The Andean orogeny () is an