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Rise of the Andes
Carmala N Garzione1, Gregory D Hoke, Julie C Libarkin
1Department of Earth and Environmental Sciences, University of Rochester, Rochester, NY 14627, USA. garzione@earth.rochester.edu
Science (New York, N.Y.)
|June 7, 2008
Summary
Mountain belt elevation changes occur rapidly, not gradually. This rapid surface uplift is driven by the removal of dense lower lithosphere after crustal thickening.
Area of Science:
- Geology
- Tectonics
- Geophysics
Background:
- Mountain belts typically rise gradually due to crustal shortening and thickening.
- Previous models assumed a continuous uplift process for mountain formation.
Purpose of the Study:
- To investigate the dynamics of surface uplift in mountain belts.
- To challenge the traditional view of gradual mountain building.
Main Methods:
- Analysis of geological data from the Andes.
- Reconstruction of elevation changes over geological timescales.
Main Results:
- Andean elevation remained stable for millions of years.
- Rapid elevation changes (over 1.5 km in 1-4 million years) were observed.
- Uplift events are punctuated and rapid.
Conclusions:
- Mountain belt uplift is not always gradual.
- Rapid surface uplift is linked to the removal of dense lower lithosphere.
- This process follows long-term crustal and lithospheric mantle thickening.
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