Subduction and collision processes in the Central Andes constrained by converted seismic phases

Details Subduction and collision processes in the Central Andes constrained by converted seismic phases Subduction and collision processes in the Central Andes constrained by converted seismic phases

Dec 2000

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2000natur.408..958y&link_type=abstract

Nature, Volume 408, Issue 6815, pp. 958-961 (2000).

Computer Science

95

Scientific paper

The Central Andes are the Earth's highest mountain belt formed by ocean-continent collision. Most of this uplift is thought to have occurred in the past 20Myr, owing mainly to thickening of the continental crust, dominated by tectonic shortening. Here we use P-to-S (compressional-to-shear) converted teleseismic waves observed on several temporary networks in the Central Andes to image the deep structure associated with these tectonic processes. We find that the Moho (the Mohorovičić discontinuity-generally thought to separate crust from mantle) ranges from a depth of 75km under the Altiplano plateau to 50km beneath the 4-km-high Puna plateau. This relatively thin crust below such a high-elevation region indicates that thinning of the lithospheric mantle may have contributed to the uplift of the Puna plateau. We have also imaged the subducted crust of the Nazca oceanic plate down to 120km depth, where it becomes invisible to converted teleseismic waves, probably owing to completion of the gabbro-eclogite transformation; this is direct evidence for the presence of kinetically delayed metamorphic reactions in subducting plates. Most of the intermediate-depth seismicity in the subducting plate stops at 120km depth as well, suggesting a relation with this transformation. We see an intracrustal low-velocity zone, 10-20km thick, below the entire Altiplano and Puna plateaux, which we interpret as a zone of continuing metamorphism and partial melting that decouples upper-crustal imbrication from lower-crustal thickening.

Affiliated with

Also associated with

No associations

Rating

Subduction and collision processes in the Central Andes constrained by converted seismic phases does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Subduction and collision processes in the Central Andes constrained by converted seismic phases, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Subduction and collision processes in the Central Andes constrained by converted seismic phases will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1054887