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Eastern China is made of a number of large and small continental fragments throughout late Paleozoic and Mesozoic time, and is still the best natural laboratory for examining kinematic models of continent tectonics. The paleoelevation history of eastern China provides direct insight into the tectonic processes in China. Here we present basalt-vesicularity based estimates of the paleoaltimetry of the early Cretaceous basalts in northern East China, which indicate that the studied basalt units were at an elevation of more than 4 kilometers in late Mesozoic. Two vesicular basaltic rocks have been collected form bottom to top along the lava flow outcrop in eastern Inner Mongolia. After the digital precessing to the sample cross-sections, and taking advantage of the stereological conversion method to acquire the bubble size distributions, paleoelevation estimate was calculated for East China in the early Cretaceous. The results show that the elevation has been near 4700±750 m when the lava flows was cooling, implying that there were highland regions in the northern part of the East China Plateau during the early Cretaceous. Combined with other geological evidence, we conclude that there was a high plateau with elevation near 5000 m above sea level in Eastern China during the late Mesozoic. This ancient high plateau in eastern China was most likely formed by the collision of the north and south China blocks. [ABSTRACT FROM AUTHOR]

We present a super-range seismic observation along the >1300-km-long profile passing through the Yinchuan basin and the Ordos block from the blasting point towards the southeast triggered by a large- (dynamite) scale coal blast in the Ningxia Hui Autonomous Region's Helan Mountain (yielded a profile). The seismic wave information from the uppermost mantle reflecting different depths was obtained by the China continental seismic survey. Pn refracted waves from the uppermost mantle were effectively traced up to 500 km and beyond. The stable dynamic and kinematic characteristics of the Pn wave- group indicate that the uppermost mantle below the Ordos block is a gently changing structure with a weak positive gradient. If Pm1, Pm2 waves are considered as the wave groups from the upper mantle, there may be distinct structural strata in the upper-mantle structures with average velocities of 7.70 - 7.80 km/s and 8.10-8.20 km/s, respectively. Based on the travel-time curve feature of Pm1, Pm2 waves, there may be a certain layer with a reverse velocity between the M1 and M2 interfaces. The depth range indicated by them is about 110-120 km and 200-220 km. These phenomena basically reflect the structural features of the upper-mantle lithosphere in this region. The information obtained may provide meaningful references for surveying North China craton lithospheric structures, as well as understanding the shapes and structures of different spherical layers within the upper-mantle. [ABSTRACT FROM AUTHOR]

Examines the tectonic deformation in Chinese mainland. Use of global positioning system velocity field in examining the characteristics; Investigation of the kinematics and dynamics of contemporary tectonic deformation of continent interior; Detection of confidence ellipse at the tip of velocity field.