Equipment Model: SmartSolo IGU-16HR 3C
Number of units: 200
The answer to the question of how the crust deforms in the tectonics of the eastern Himalayas during the collision of the Indian and Asian plates is still unclear. Here we show for the first time high-resolution receiver function images of crustal structures along a new NW-SE-trending dense array of stations crossing the Himalayan tectonic belt. We observe two sets of low-velocity zones, one below the western part of the Lhasa Massif and the High Himalayan region at a depth of 18 ~ 20 km, which is flat; and the other below the western part of the Yarlung Tsangpo Suture Belt at a depth of 10 ~ 30 km, which is two westward-trending types. These low-velocity zones caused by partially molten and aqueous fluids are separated from each other and impede the formation of crustal flows. Under the Ankiga-Motoro shear zone, an eastward-dipping internal crustal discontinuity and a pronounced Moho dislocation with a length of 7 Km are identified, suggesting that retrogression of the subducting crust beneath the Indian Plate and a pure shear mechanism together dominate crustal deformation in the Eastern Himalayan tectonic belt.
Blue inverted triangles are dense stations consisting of 200 IGU-16HR 3Cs