[1] Using the measurements of 750 GPS stations around the Tibetan Plateau for over 10 years since 1999, we derived a high-resolution 3-D velocity field for the present-day crustal movement of the plateau. The horizontal velocity field relative to stable Eurasia displays in details the crustal movement and tectonic deformation features of the India-Eurasia continental collision zone with thrust compression, lateral extrusion, and clockwise rotation. The vertical velocity field reveals that the Tibetan Plateau is continuing to rise as a whole relative to its stable north neighbor. However, in some subregions, uplift is insignificant or even negative. The main features of the vertical crustal deformation of the plateau are the following: (a) The Himalayan range is still rising at a rate of~2 mm/yr. The uplift rate is 6 mm/yr with respect to the south foot of the Himalayan range. (b) The middle eastern plateau has a typical uplift rate between 1 and 2 mm/yr, and some high mountain ranges in this area, like the Longmen Shan and Gongga Shan, have surprising uplift rates as large as 2-3mm/yr. (c) In the middle southern plateau, there is a basin and endorheic subregion with a series of NS striking normal faults, showing obvious sinking with the rates between 0 and -3 mm/yr. (d) The present-day rising and sinking subregions generally correspond well to the Cenozoic orogenic belts and basins, respectively. (e) At the southeastern corner of the plateau. There is an apparent trend that the uplift rate is gradually decreasing from between 0.8 and 2.3 mm/yr in the inner plateau to between -0.5 and -1.6 mm/yr outside the plateau, with the decrease of terrain height.Citation: Liang, S., W. Gan, C. Shen, G. Xiao, J. Liu, W. Chen, X. Ding, and D. Zhou (2013), Three-dimensional velocity field of present-day crustal motion of the Tibetan Plateau derived from GPS measurements,

Ionospheric F2 region peak densities (NmF2) are expected to have a positive correlation with total electron content (TEC), and electron densities usually show an anticorrelation with electron temperatures near the ionospheric F2 peak. However, during the 17 March 2015 great storm, the observed TEC, NmF2, and electron temperatures of the storm‐enhanced density (SED) over Millstone Hill (42.6°N, 71.5°W, 72° dip angle) show a quiet different picture. Compared with the quiet time ionosphere, TEC, the F2 region electron density peak height (hmF2), and electron temperatures above ~220 km increased, but NmF2 decreased significantly within the SED. This SED occurred where there was a negative ionospheric storm effect near the F2 peak and below it, but a positive storm effect in the topside ionosphere. Thus, this SED event was a SED in TEC but not in NmF2. The very low ionospheric densities below the F2 peak resulted in a much reduced downward heat conduction for the electrons, trapping the heat in the topside in the presence of heat source above. This, in turn, increased the topside scale height so that even though electron densities at the F2 peak were depleted, TEC increased in the SED. The depletion in NmF2 was probably caused by an increase in the density of the molecular neutrals, resulting in enhanced recombination. In addition, the storm time topside ionospheric electron density profiles were much closer to diffusive equilibrium than the nonstorm time profiles, indicating less daytime plasma flow between the ionosphere and the plasmasphere.

The Yardoi gneiss dome is located to the easternmost of the North Himalayan Gneiss Dome (NHGD), southern Tibet. It consists of metapelite, garnet amphibolite, granite and leucogranite, and is a key subject to constrain the formation and tectonic evolution of NHGD. SHRIMP zircon U/Pb data on the leucogranite yield an age of 35.3±1.1 Ma, which is substantially older than that of the similar leucogranites to the west. Sr and Nd isotope systematics indicate that this leucogranite was derived from partial melting of the mixed garnet amphibolite and metapelite. Our data suggest that (1) during the early stage of Himalayan magmatism, amphibolite dehydration melting overwhelmed that of the metapelite; and (2) such a melting at middle-lower crust might be a major factor that initiated the movement along the Southern Tibetan Detachment System (STDS). leucogranite, metapelite, crustal anatexis, Himalayan Orogenic Belt, North Himalayan Gneiss DomeConvergence between the Indian and Eurasian plates resulted in intensive structural deformation, high-grade metamorphism and crustal anatexis in the Himalayan Orogenic Belt. In southern Tibet, the post-collisional tectonics is represented by the development of concurrent N-S compression and extension [1][2][3][4][5] , and intensive crustal anatexis [6][7][8][9][10] which formed two subparallel granitic belts separated by the Southern Tibetan Detachment System (STDS), e.g. the High Himalayan Granitic belt (HHG) to the south, and the North Himalayan Gneiss Dome (NHGD) to the north (Figure 1(a)). They have preserved the records on the nature of deformation, high-grade metamorphism, crustal anatexis and near-surface processes associated with the active continental collision between the Indian and Eurasian plates. Documenting the timing and nature of these processes is essential to addressing the way of interplay and degree of coupling between these processes. A large number of studies have been directed toward better understanding different aspects of the HHG and yielded abundant meaningful information with regard to how the crust behaved during the collision [1][2][3][4][5][6][7][8][9][10][11][12] . However, much less effort has been made on the NHGD.Gneiss and amphibolites within the NHGD commonly experienced amphibolite to granulite facies metamorphism at T > 800℃, and P > 800 MPa. Partial melting at these conditions is widespread and represented by the occurrence of migmatite and leucogranites [13][14][15][16] . Available data show that these high-grade metamorphic rocks and leucogranites have similar mineral and isotope compositions to those in the HHG, and experienced similar deformation. They were considered as the northern extension of High Himalaya Crystalline Sequence (HHCS) [16] . Both suites of rock from NHGD and HHG have been regarded as a mid-lower crustal channel [17,18] . Metamorphic rocks and granites in the NHGD are structurally lower than STDS. Knowledge of the relationship between NHGD and STDS is critical to test tectonic models for the evolution of southern Tibet