Why is the tectonic plate ‘Nazca’ called Nazca?
Feb.14, 2012 in
Nazca
Question by babycakes-x: Why is the tectonic plate ‘Nazca‘ called Nazca?
All the other plates are named after the continents they are under, but this is a difference.
Best answer:
Answer by Brian L
It’s named after the Nazca region of Peru.
Add your own answer in the comments!
February 14th, 2012 at 3:08 am
Nazca (sometimes spelled Nasca) is the name of a system of valleys on the southern coast of Peru, and the name of the region’s largest existing town. It is also the name applied to the Nazca culture that flourished in the area between 300 BC and AD 800. They were responsible for the Nazca Lines and the ceremonial city of Cahuachi; they also constructed an impressive system of underground aqueducts that still function today.
The Nazca Plate, named after the Nazca region of southern Peru, is an oceanic tectonic plate in the eastern Pacific Ocean basin off the west coast of South America.
The eastern margin is a convergent boundary subduction zone under the South American Plate and the Andes Mountains, forming the Peru-Chile Trench. The southern side is a divergent boundary with the Antarctic Plate, the Chile Rise, where seafloor spreading permits magma to rise. The western side is a divergent boundary with the Pacific Plate, forming the East Pacific Rise. The northern side is a divergent boundary with the Cocos Plate, the Galapagos Rise. A triple junction occurs at the northwest corner of the plate where the Nazca, the Cocos, and the Pacific plates all join off the coast of Colombia. A second triple junction occurs at the southwest corner at the intersection with the Nazca, the Pacific, and the Antarctic plates off the coast of southern Chile. At each of these triple junctions an anomalous microplate exists, the Galapagos Microplate at the northern junction and the Juan Fernandez Microplate at the southern junction. The Easter Island Microplate is a third microplate that is located just north of the Juan Fernandez Microplate and lies just west of Easter Island.
Yet another triple junction occurs where the Nazca, Antarctic and South American plates meet. This triple junction has been considered to be related to the moment magnitude 9.5, 1960 megathrust earthquake known as the Great Chilean Earthquake.
Luckily, very few islands are there to suffer the earthquakes that are a result of complicated movements at these junctions. Juan Fernández Islands is an exception.
The Carnegie Ridge is a 1350-km-long and up to 300-km-wide feature on the ocean floor of the northern Nazca Plate that includes the Galápagos archipelago at its western end. It is being subducted under South American with the rest of the Nazca Plate.
The absolute motion of the Nazca Plate has been calibrated at 3.7 cm/yr east motion (88°), some of the fastest absolute motion of any tectonic plate. The subducting Nazca Plate, which exhibits unusual flat-slab subduction, is tearing as well as deforming as it is subducted (Barzangi and Isacks) has formed, and continues to form the volcanic Andes Mountain Range. Deformation of the Nazca Plate even affects the geography of Bolivia, far to the east (Tinker et al.).
The precursor of the Nazca Plate and the Cocos Plate to its north was the Farallon Plate, which split in late Oligocene times, about 22.8 My, a date arrived at by interpreting magnetic anomalies.