Himalayan Tectonics: A Modern Synthesis
CONTAINS OPEN ACCESS
The Himalaya–Karakoram–Tibet mountain belt resulted from Cenozoic collision of India and Asia and is frequently used as the type example of a continental collision orogenic belt. The last quarter of a century has seen the publication of a remarkably detailed dataset relevant to the evolution of this belt. Detailed fieldwork backed up by state-of-the-art structural analysis, geochemistry, mineral chemistry, igneous and metamorphic petrology, isotope chemistry, sedimentology and geophysics produced a wide-ranging archive of data-rich scientific papers. The rationale for this book is to provide a coherent overview of these datasets in addressing the evolution of the mountain ranges we see today.
This volume comprises 21 specially invited review papers on the Himalaya, Kohistan arc, Tibet, the Karakoram and Pamir ranges. These papers span the history of Himalayan research, chronology of the collision, stratigraphy, magmatic and metamorphic processes, structural geology and tectonics, seismicity, geophysics, and the evolution of the Indian monsoon. This landmark set of papers should underpin the next 25 years of Himalayan research.
The isotopic evolution of the Kohistan Ladakh arc from subduction initiation to continent arc collision
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Published:October 08, 2019
Abstract
Magmatic arcs associated with subduction zones are the dominant active locus of continental crust formation, and evolve in space and time towards magmatic compositions comparable to that of continental crust. Accordingly, the secular evolution of magmatic arcs is crucial to the understanding of crust formation processes. In this paper we present the first comprehensive U–Pb, Hf, Nd and Sr isotopic dataset documenting c. 120 myr of magmatic evolution in the Kohistan-Ladakh paleo-island arc. We found a long-term magmatic evolution that is controlled by the overall geodynamic of the Neo-Tethys realm. Apart from the post-collisionnal melts, the intra-oceanic history of the arc shows two main episodes (150–80 Ma and 80–50 Ma) of distinct geochemical signatures involving the slab and the sub-arc mantle components that are intimately linked to the slab dynamics.
- absolute age
- alkaline earth metals
- Asia
- composition
- continental crust
- controls
- crust
- crustal thickening
- crustal thinning
- dates
- diorites
- geodynamics
- hafnium
- Hf-177/Hf-176
- ICP mass spectra
- igneous rocks
- Indian Peninsula
- island arcs
- isotope ratios
- isotopes
- Jammu and Kashmir
- Jurassic
- Kohistan
- Ladakh
- lead
- magmas
- magmatism
- mantle
- mass spectra
- melts
- Mesozoic
- metals
- models
- Nd-144/Nd-143
- neodymium
- Neotethys
- Pb-206/Pb-204
- Pb-207/Pb-204
- Pb-208/Pb-204
- plate collision
- plate tectonics
- plutonic rocks
- radioactive isotopes
- rare earths
- reconstruction
- samarium
- slabs
- spectra
- Sr-87/Sr-86
- stable isotopes
- strontium
- subduction
- subduction zones
- thermal ionization mass spectra
- tonalite
- U/Pb
- Upper Jurassic
- variations
- whole rock
- X-ray fluorescence spectra
- Sm-147/Sm-144