Extent
The Alice Springs orogeny was centered in an area that had previously been a marine sedimentary basin, and involved the thrusting up of the underlying metamorphic and igneous rocks of Proterozoic age.
The Alice Springs Orogeny had its beginnings in the Late Ordovician, continuing during the Silurian and Devonian, and by the Carboniferous the folding of the sedimentary deposits of the central Australian basins had produced the mountainous terrain of the MacDonnell Ranges area. Today we see only the eroded remnants of these former mountains in the MacDonnell Ranges and other ranges throughout much of central Australia.
Prior to the Alice Springs Orogeny the Amadeus, Georgina, Wiso and Ngalia sedimentary basins were adjoining. The Alice Springs Orogeny disentombed the Arunta Inlier during mainly south-directed thrusting. Sediment was eroded off the rising mountain belt to result in the deposition of thick foreland sediments which became incorporated into the remaining relics of the former sedimentary basin, becoming the Amadeus, Georgina and Ngalia basins that are preserved today.
Read more about this topic: Alice Springs Orogeny
Famous quotes containing the word extent:
“It is strange to contemplate how little sympathy or encouragement the great mass of people have with one who differs from them in tastes, to the extent of desiring an education, while they are content with little or none.”
—Caroline Nichols Churchill (1833–?)
“In the extent and proper structure of the Union, therefore, we behold a republican remedy for the diseases most incident to republican government.”
—James Madison (1751–1836)
“Cannibalism to a certain moderate extent is practised among several of the primitive tribes in the Pacific, but it is upon the bodies of slain enemies alone; and horrible and fearful as the custom is, immeasurably as it is to be abhorred and condemned, still I assert that those who indulge in it are in other respects humane and virtuous.”
—Herman Melville (1819–1891)