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Trans-Pecos Volcanic Field
The Trans-Pecos Volcanic Field is a volcanic field located in western Texas in the counties of Brewster, Jeff Davis, Presidio, and extends into northern Mexican states of Chihuahua and Coahuila. It is the southernmost volcanic field to be documented and recorded in the continental United States. The field started volcanic activity around 48 million years ago in the middle Eocene epoch, and ended around 17 million years later in the Miocene epoch. The Volcanic field is the result of Ancient Subduction off the western portion of the continent at the time. Most of the volcanoes in the field are calderas. Some of the volcanoes are: *In Big Bend National Park, the Christmas Mountains caldera complex and Pine Canyon caldera complex *In Big Bend Ranch State Park, the Bofecitos mountains center and the Solitario *Near Alpine, the Paisano Volcano *In northern Jeff Davis County, the Davis Mountains Caldera Complex *In central Presidio County, the Chinati Mountain Caldera Complex ... [...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] |
Pine Canyon Caldera Complex
The Pine Canyon Caldera Complex is a caldera complex located in Big Bend National Park of Texas. The complex is located in the southern part of the Chisos Mountains in the South Rim Formation. The caldera was formed by several rhyolitic Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture, but may be porphyritic, containing larger mineral crystals (phenocrysts) in an otherwise fine-grained groundmass. The mineral ... eruptions about 32 million years ago. It is considered a downsag caldera (a type of collapsed caldera), meaning it lacks surficial faulting. The Pine Canyon Caldera also is believed to have been created from crust (geology), crustal stretching during the Ouachita orogeny. Also in the northern part of the caldera, high magnetic waves are present and are believed to be from a broad intrusion, which tends to mean a partial crustal boundary of the Ouachita orogeny. This feature represents the largest in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
