Carbonate- and silicate-metasomatized mantle beneath Himalayan-Tibetan orogenic belt
Weikai Li1,2,3, Zhiming Yang1, Zoltán Zajacz3
1State Key Laboratory of Deep Earth and Mineral Exploration, Institute of Geology, Chinese Academy of Geological Sciences, Beijing, China.
None:
The extreme geochemical enrichment of post-collisional potassium-rich lava in the Alpine-Himalayan orogenic belt has led researchers to hypothesize that enrichment is inherited from a metasomatized mantle source potentially incorporating crustal components. However, direct verification of metasomatic processes remains challenging due to the scarcity of mantle rocks preserving metasomatism records. Here, we report two groups of mantle xenolith entrained in Tibetan ultrapotassic lavas. Integrated petrographic observations, whole-rock geochemistry, and in-situ microanalysis reveal that subcontinental lithospheric mantle exhibits extreme enrichment in both isotopes and incompatible elements. Textural evidence of vein networks and melt pockets in xenoliths indicate the coexistence of carbonate and silicate metasomatic regimes. Considering subduction-collision background, we propose that the recycling of Indian continental materials during collision substantially contributes to the metasomatic enrichment of the Tibetan subcontinental lithospheric mantle.
More Related Videos
07:58Data Processing Methods for 3D Seismic Imaging of Subsurface Volcanoes: Applications to the Tarim Flood Basalt
Published on: August 7, 2017
06:55Kinematic History of a Salient-recess Junction Explored through a Combined Approach of Field Data and Analog Sandbox Modeling
Published on: August 5, 2016
Related Concept Videos
Magnetostatic Boundary Conditions
Minerals
Major...
Theory of Metallic Conduction
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...
Network Covalent Solids
To break or to melt a covalent network solid, covalent bonds must be broken. Because covalent bonds are relatively strong, covalent network solids are typically...
Region of Convergence of Laplace Tarnsform
Consider a decaying exponential signal that begins at a specific time. When deriving its Laplace transform, the time-domain variable is replaced with a complex variable. This...
Phase Transitions: Sublimation and Deposition
