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Carnegie Ridge
The Carnegie Ridge is an aseismic ridge on the Nazca Plate that is being subducted beneath the South American Plate. The ridge is thought to be a result of the passage of the Nazca Plate over the Galapagos hotspot. It is named for the research vessel '' Carnegie'', which discovered it in 1929. Extent The Carnegie Ridge is seen to extend eastwards over 1,000 km from the Galapagos islands to the Colombia-Ecuador trench and is interpreted to continue beneath northern Ecuador for about a further 700 km. The subducted extent is disputed, with some workers arguing that there is no evidence of a subducted ridge beneath Ecuador extending more than about 60 km from the trench. Structure The Carnegie Ridge consists of thickened oceanic crust. Wide-angle seismic reflection and refraction data acquired over the central and eastern part of the ridge give crustal thicknesses of 13 km and 19 km respectively for crust that has estimated ages of about 11 Ma and 20 Ma. L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carnegie Ridge
The Carnegie Ridge is an aseismic ridge on the Nazca Plate that is being subducted beneath the South American Plate. The ridge is thought to be a result of the passage of the Nazca Plate over the Galapagos hotspot. It is named for the research vessel '' Carnegie'', which discovered it in 1929. Extent The Carnegie Ridge is seen to extend eastwards over 1,000 km from the Galapagos islands to the Colombia-Ecuador trench and is interpreted to continue beneath northern Ecuador for about a further 700 km. The subducted extent is disputed, with some workers arguing that there is no evidence of a subducted ridge beneath Ecuador extending more than about 60 km from the trench. Structure The Carnegie Ridge consists of thickened oceanic crust. Wide-angle seismic reflection and refraction data acquired over the central and eastern part of the ridge give crustal thicknesses of 13 km and 19 km respectively for crust that has estimated ages of about 11 Ma and 20 Ma. L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cocos Plate
The Cocos Plate is a young oceanic tectonic plate beneath the Pacific Ocean off the west coast of Central America, named for Cocos Island, which rides upon it. The Cocos Plate was created approximately 23 million years ago when the Farallon Plate broke into two pieces, which also created the Nazca Plate. The Cocos Plate also broke into two pieces, creating the small Rivera Plate. The Cocos Plate is bounded by several different plates. To the northeast it is bounded by the North American Plate and the Caribbean Plate. To the west it is bounded by the Pacific Plate and to the south by the Nazca Plate. __TOC__ Geology The Cocos Plate was created by sea floor spreading along the East Pacific Rise and the Cocos Ridge, specifically in a complicated area geologists call the Cocos-Nazca spreading system. From the rise the plate is pushed eastward and pushed or dragged (perhaps both) under the less dense Caribbean Plate, in the process called subduction. The subducted leading edge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypocenter
In seismology, a hypocenter or hypocentre () is the point of origin of an earthquake or a subsurface nuclear explosion. A synonym is the focus of an earthquake. Earthquakes An earthquake's hypocenter is the position where the strain energy stored in the rock is first released, marking the point where the fault begins to rupture.''The hypocenter is the point within the earth where an earthquake rupture starts. The epicenter is the point directly above it at the surface of the Earth. Also commonly termed the focus.'' This occurs directly beneath the epicenter, at a distance known as the ''hypocentral depth'' or ''focal depth''. The focal depth can be calculated from measurements based on seismic wave phenomena. As with all wave phenomena in physics, there is uncertainty in such measurements that grows with the wavelength In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats. It is the distance between co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
