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El Negrillar
El Negrillar is a volcanic field in the Andes. Located south of the Salar de Atacama and west of the Cordón de Púlar, it generated cinder cones and lava flows. Covering a surface area of , it is the largest volcanic field in northern Chile, with almost a hundred vents that produced mainly lava flows. Owing to the arid climate, landforms are well preserved. Radiometric dating has yielded ages of less than 1.5 million years, with the most recent eruption occurring about 141,000 years ago. Parts of the Holocene Socompa debris avalanche overlie the field. A groundwater system underlies the volcanic field and some cones formed through phreatomagmatic eruptions. El Negrillar is located in a complex tectonic regime, characterized by numerous Fault (geology), faults. The town of Tilomonte and various power lines, mines and water wells are in the area. Geography and geomorphology The Central Volcanic Zone (CVZ) of the Andes is a northwest-south trending volcanic arc that extends from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Field
A volcanic field is an area of Earth's crust that is prone to localized volcanic activity. The type and number of volcanoes required to be called a "field" is not well-defined. Volcanic fields usually consist of clusters of up to 100 volcanoes such as cinder cones. Lava flows may also occur. They may occur as a monogenetic volcanic field or a polygenetic volcanic field. Description Alexander von Humboldt observed in 1823 that geologically young volcanoes are not distributed uniformly across the Earth's surface, but tend to be clustered into specific regions. Young volcanoes are rarely found within cratons, but are characteristic of subduction zones, rift zones, or in ocean basins. Intraplate volcanoes are clustered along hotspot traces. Within regions of volcanic activity, volcanic fields are clusters of volcanoes that share a common magma source. Scoria cones are particularly prone to cluster into volcanic fields, which are typically in diameter and consist of several tens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
