Huntington et al.(2006)による〔『Climate change and Late Pliocene acceleration of erosion in the Himalaya』(107p)から〕

『ヒマラヤにおける気候変動と後期鮮新世の浸食促進』


Abstract
 Studies of active mountain ranges suggest that atmospheric and geodynamic processes may be strongly coupled through erosion - a hypothesis that has led to a debate over the relative importance of climate and far-field tectonic forcing in influencing erosion. We addressed this debate by developing the detailed long-term erosional history of a transect in the central Annapurna Range of Nepal for comparison with the climate and tectonic forcing histories of the region. Patterns of apatite fission-track and muscovite 40Ar/39Ar apparent ages with elevation indicate a five-fold increase in apparent erosion rate between 2.5 and 0.9 Ma ago. The time frame for this change corresponds to that of global climate destabilization associated with the onset of Northern Hemisphere glaciation and an intensification of the Asian monsoon. There is no evidence for important changes in the far-field tectonics of the Himalayan-Tibetan orogenic system over that interval, suggesting a largely climatic driver for enhanced erosion at the Himalayan range front.

Keywords: Himalaya; erosion; climate; fission-track geochronology; Argon geochronology』

1. Introduction
2. Approach and geologic setting
3. Fission-track analytical methods
4. Results and interpretations
5. Corroborating evidence for a 2.5-0.9 Ma change in erosion rate in the central Himalaya
6. Arguments in favor of climate change as the cause of accelerated erosion
7. Evidence for late-stage slip near the trace of the Main Central thrust
8. Discussion and conclusions
Acknowledgements
Appendix A. Statistical comparison of apatite fission-track and muscovite 40Ar/39Ar age-elevation gradients
Appendix B. Thermal model details
References
References cited in Appendix B


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