|
The geology of Chile is a result of the Andean and preceding orogenies occurring on the western coast of South America, a convergent boundary of tectonic plates. During the Paleozoic and Precambrian periods, the boundary was shaped by terranes and microcontinents before developing into a pure subduction zone. The subduction shaped four main geological features: the Andes; the Intermediate Depression, a graben and foreland basin; the Coast Range (a horst), and the Peru–Chile Trench off the coast. Since Chile is on an active continental margin, it has a large number of volcanoes. Almost the entire country is subject to earthquakes arising from strains in the Nazca and Antarctic Plates or shallow strike-slip faults. Northern Chilean mineral resources are a major export, and the country is the leading producer of copper, lithium and molybdenum. Most of these mineral deposits were created from magmatic hydrothermal activity. The water required to form those deposits derived from the subducted slab of the oceanic crust beneath the Andes. The Chilean Easter Island and Juan Fernández Archipelago are volcanic hotspot islands in the eastward-moving Nazca plate. Features of the Antarctic Peninsula, claimed as part of the Chilean Antarctic Territory, are shared with the southern Andes. ==General characteristics== The three primary morphological features derived from the Andes are the Andes Mountains proper, the Chilean Coast Range and the Chilean Central Valley, also known as the Intermediate Depression and the Longitudinal Valley. The mountains run parallel in a north-south direction from Morro de Arica to Taitao Peninsula, making up most of Chile's land surface. South of Taitao, only the Andes Mountains are present. North of the Taitao Peninsula, the Peru–Chile Trench subduction zone is the boundary between the South American and Nazca Plates. At Taitao, the Chile Triple Junction and the Nazca Plate subduct the South American Plate. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Geology of Chile」の詳細全文を読む スポンサード リンク
|