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Mount Price is a small stratovolcano in the Garibaldi Ranges of the Pacific Ranges in southwestern British Columbia, Canada. It is located southeast of the abandoned settlement of Garibaldi above the eastern flank of the Cheakamus River valley. With a summit elevation of and a topographic prominence of , it rises above the surrounding landscape on the western shore of Garibaldi Lake. A large provincial park surrounds Mount Price and other volcanoes in its vicinity. Its northern and western flanks are overlapped by smaller volcanic edifices, such as Clinker Peak, which was the source for two thick lava flows about 10,000 years ago that ponded against glacial ice. These volcanoes were formed by volcanic eruptions from secondary vents rather than individual ones. As a result, Clinker Peak and other flank volcanoes are interpreted to be part of Mount Price. The mountain is associated with a small group of related volcanoes called the Garibaldi Lake volcanic field. This forms part of the larger Garibaldi Volcanic Belt, a north-south trending volcanic zone that represents a portion of the Canadian Cascade Arc. Mount Price began its formation 1.2 million years ago and activity continued intermittently until about 10,000 years ago. Even though the mountain has not erupted since the early Holocene epoch, it could erupt again, which would potentially pose danger to the nearby populace. If this were to happen, relief efforts would be quickly organized. Teams such as the Interagency Volcanic Event Notification Plan (IVENP) are prepared to notify people threatened by volcanic eruptions in Canada. ==Geology== Mount Price is one of the three principal volcanoes in the southern segment of the Garibaldi Volcanic Belt. In contrast to most stratovolcanoes in Canada, Mount Price has a nearly symmetrical structure. It is one of the several Garibaldi Belt volcanoes that have been active in the Quaternary period. Clinker Peak, a breached volcanic crater on its western flank, was formed during a period of volcanic activity about 10,000 years ago.〔 Oxidation of Price's volcanic rocks has given the mountain a red colour. Like other volcanoes in the Garibaldi Volcanic Belt, Mount Price formed as a result of subduction zone volcanism. As the Juan de Fuca Plate subducts under the North American Plate at the Cascadia subduction zone, it forms volcanoes and volcanic eruptions.〔 Unlike most subduction zones worldwide, there is no deep oceanic trench present along the continental margin in Cascadia. There is also very little seismic evidence that the Juan de Fuca Plate is actively subducting. As a result, the existence of active volcanism in the Cascade Volcanic Arc is the best evidence for ongoing subduction. However, volcanic activity along the Cascade Arc has been declining over the last few million years. The probable explanation lies in the rate of convergence between the Juan de Fuca and North American plates. These two tectonic plates currently converge at a rate of to per year, only about half the rate of convergence from seven million years ago. This slowed convergence likely accounts for reduced seismicity and lack of an oceanic trench.〔 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「Mount Price (British Columbia)」の詳細全文を読む スポンサード リンク
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