This project will be based on the comparison of the process of lithospheric removal in the regions of Antiplano Plateau, located in the Andes, South America. The process of subduction characterizes this region. The Andes, is part of a convergent margin where the Nazca Plate is subducting beneath the South American Plate
In attempt to explain numerous geodynamic processes and geophysical anomalies found at active and passive continental rifts the concept of lithospheric removal was created. The lithospheric removal can cause rapid uplift, increased surface heat flow, lowered shallow mantle seismic velocities, and increased magmatism (Byerly and Lassiter, 2012).
According to Isacks (1988) the Antiplano is the second largest plateau in Earth, with size of approximately 400 km and 2000 km longer, and the elevation is near 4 km. Additionally, this region is the highest plateau related with richness of magmatic arc (Allmendinger, Jordan, Kay, and Isacks, 1997). The region is constituted by southern Peru, Bolivia, northern Chile and Puna(Argentina). Study of stable isotopes in authigenic carbonates in the Altiplano inferences of post-10 Ma of the Andean plateau’s rise. In the late Miocene epoch, the Andean plateau suffers a rapid surface uplift of many kilometers, rate of approximately 3 ± 1 Myr. On top of that, this rate is too high to be generated by only crustal shortening. So, the removal of relatively dense eclogite and mantle lithosphere is a required process in this situation (Molnar and Garzione, 2006).
According to Molnar and Garzione (2006), the thermal and structural characteristics of crust and mantle as well the volcanic history are consistent with removal of mantle lithosphere and eclogite lower crust from below Andean Plateau. In the Central of Altiplano the crustal thickness varies between 59 to 64 km. In addition, the highest topography in Central Andes, is located in Eastern and Western Cordilleras with approximately 70 km. This fact suggests the Airy Isostatic balance in this region (Beck and Zandt, 2002).
All of mantle lithosphere has been removed from the region of Altiplano since the seismic tomography of 16 ° and 20 ° (Northen Chile and Bolivia) shows the lowest P wave speed below this region. Additionally, beneath the Altiplano the crustal column suggest a felsic composition because of the high-speed of lower crust (Beck and Zandt, 2002).
The surface uplift of thousand meters in a great region...