Crustal structure of the northeastern margin of the Tibetan plateau from the Songpan-Ganzi terrane to the Ordos basin

Three-dimensional S-wave velocity structure in eastern Tibet from ambient noise Rayleigh and love wave tomography

“…7 clearly display the spatial distributions of the S-wave low-velocity layers which are probably related to weak crustal materials. Combined with previous researches (Bai et al, 2010;Zhang et al, 2010;Li et al, 2009;Yao et al, 2008;Wang et al, 2007;Liu et al, 2006), our 3-D S-wave velocity model could give some information for an interpretation on crustal flow model that the crustal materials in eastern Tibet escape firstly in an easterly direction, then are resisted by the rigid Sichuan basin and redirected into southeastward and northeastward. The steep topographic gradient along the Longmenshan fault belt in the eastern margin of the plateau is due to the strong interaction between the escaped eastern Tibetan plateau and the stable Sichuan basin.…”

Tectonic Models for the Evolution of Sedimentary Basins

“…These findings are consistent with models in which decoupled lithospheric folds with 30 and 400 km wavelength correspond to, respectively, crustal folding and mantle folding. Deep seismic data for basins north of and within the Tibetan Plateau (Liu et al, 2006;Zhao et al, 2006) show that folding is not limited to the Tibetan Plateau (see also Shin et al, 2009 Cloetingh et al (2002), Tertiary lithospheric folding of Iberia occurs in Variscan lithosphere with wavelengths of 300 km, leading to the development of a system of parallel trending basins and highs (Figure 45(a)). This folding generated the distribution of basins and mountain chains, bounded by folds and faults De Vicente et al, 2007).…”

Crustal velocity structure of central Gansu Province from regional seismic waveform inversion using firework algorithm

“…15, 15.69, 13.08, and 14.83 km, respectively, while v P values are 4.47, 6.07, 6.12, and 6.87 km/s, respectively, and the inverted v P of the uppermost mantle is 8.18 km/s. In a previous study, Liu et al (2006) used v P intervals to determine the crustal composition of the northeastern margin of the Qinghai-Tibet plateau; the results of this study show that both the upper and middle crust contain felsic material, encompassing a total thickness of 28.77 km, while intermediate material is present in the lower crust, which has a thickness of 14.83 km.…”