This file includes figures, tables, models divided into seven Data Repository (DR) items: 2013); Q4, Holocene. We highlight the uplift of Q2 (middle Pleistocene Ya'an Formation) and its corresponding age, and then translate this uplift to a slip based on the relationship from Shaw et al., (2002) assuming a fault dip of 33-56°. Final, we obtain the range of slip rate for the RFBT to be 0.13-0.39 mm/yr. Figure DR4: Interpretation of industry seismic reflection profile L2 in the Sichuan basin, modified from our previous study by Jia et al., (2010). The large rectangle denotes the locations of Figure 4a, showing the hanging wall deformation associated with the RFBT. The small rectangle denotes the location of shallow seismic reflection profile B, which is shown on Fig. 4b. The RFBT extends into the basin, and forms the structural wedge, with its wedge-tip at about 8-9 km. The hanging wall of the RFBT contains a kink band, which extend from the ramp to the surface. This kink band is formed by the splay fault on the RFBT, thus the growth triangle on the shallow seismic reflection profile B records the activity on the RFBT. The range of possible splay fault dips is 33°-56°, which is constrained using the dips range of the axial surface (upper limit) and the ramp dips (lower limit) on the RFBT. Figure DR5: Interpretation of industry seismic reflection profile E in the Sichuan basin. The large rectangle denotes the locations of shallow seismic reflection profile C, which is shown on Fig. 4c. A splay fault of the RFBT rises from the ramp to the near surface, and displaces geological Triassic and younger layers in the hanging wall. We interpret this fault propagates to the shallow surface, producing the tip folding, and forming two back thrusts, which are shown on shallow section C. PGT, Pengguan thrust fault; RFBT, Range Front blind thrust, J, Jurassic; T, Triassic. Data Repository Item DR6 Data Repository Item DR7

Rivaling the Himalaya in relief, the Longmen Shan is probably one of the most enigmatic mountain ranges in the world: high mountains reach more than 4000 m relief but without adjacent foreland subsidence and with only slow active convergence. What are geological and geodynamic processes that built the Longmen Shan? Coseismic deformation associated with the 2008 Wenchuan earthquake could hold clues to answer these questions. The primary features associated with the 2008 Wenchuan earthquake rupture have been narrowly distributed coseismic deformation and predominantly vertical displacements that could be interpreted as the result of slips on high‐angle listric seismogenic faults. Deep sounding seismic reflection profiling across the seismogenic faults indeed reveals high‐angle listric reverse faulting in the brittle upper crust and east‐dipping reflectors that we interpret as ductile shearing, in the viscous lower crust. In conjunction with a visco‐elastic finite element modeling of coseismic displacements associated with the Wenchuan earthquake, we show that the high‐angle listric nature of earthquake faults produces insignificant horizontal shortening across the fault and facilitates upward slips along the fault that both explain the localized coseismic deformation and vertical displacement, as well as the presence of high mountains without adjacent foreland flexure. We suggest that the formation of the Longmen Shan may be better understood in terms of partitioned lithospheric pure‐shear thickening in which upward high‐angle listric faulting of brittle upper crust is linked to thickening of the more viscous lithospheric mantle through downward ductile shearing of rheologically deformable lower crust.

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The fine crustal structure and tectonics of the Beijing region are explored by using a 100 km long, NW-trending deep seismic reflection profile. This profile passed through the Sanhe-Pinggu earthquake (M 8.0) area and main faults in the Beijing region. The results show that the crust beneath the investigated area is divided into upper and lower crust by a strong reflective zone at about 6∼7 s TWT. The thickness of the upper and lower crust is about 18∼21 km and 13∼15 km, respectively. There are rich reflective layers and clear structural patterns above 3∼4 s TWT as well as obviously different structural features along the profile. In the west of the Sanhe-Pinggu earthquake area, the stacked deep seismic reflection section shows 2∼3 groups of strong reflective layers and a series of basement faults. In the east of the Sanhe-Pinggu earthquake area, there is a set of dense, west-dipping, reflective strata with relatively strong energy, which have the typical characteristics of a sedimentary basin. The largest depth of the sedimentary basin is about 8∼9 km. The deep fault in crust revealed by the deep seismic reflection profile has a steep plane, and it cuts and disturbs the lower crust and crust-mantle transitional zone. This deep fault extends upwards into the upper crust, and joins the crustal deep structure to the shallow fault. The profile reveals that the deep-shallow fault system represents the major deep-shallow tectonic feature in the study region.

Reliable estimates of Quaternary or Cenozoic upper crustal shortening in the Longmen Shan fold‐and‐thrust belt are rare. In this paper, we report on our use of high‐resolution 2‐D and 3‐D seismic reflection profiles at various scales, together with borehole data, to investigate the structural geometry of the Longmen Shan piedmont. The results reveal a thrust system beneath the Longmen Shan, termed the range front thrust system, which consists of the range front blind thrust and its upward splay faults. Moreover, on these faults we identified growth strata that provide an excellent opportunity for assessing the activity of this thrust system. Analyses of the growth strata reveal early to late Pleistocene activity on the range front blind thrust, with minimum dip slip and horizontal shortening rates of 1.1 ± 0.2 mm/yr and ~1 mm/yr. Accordingly, the maximum accumulated slip on the range front blind thrust is calculated to be 7.5 ± 0.3 km in the Longmen Shan. Using the new horizontal shortening rate and other published data, we also estimated that the long‐term shortening rate across the Longmen Shan fold‐and‐thrust belt is 1–3 mm/yr, which is comparable to the short‐term GPS rate. The similarity of these rates suggests that the Longmen Shan attained a steady state condition over the past 2 Myr. An additional highlight of our results is that we show Quaternary activity around the Tibetan Plateau to have been nearly synchronous in different regions, including in the Longmen Shan, the Himalayas, the western Kunlun Shan, and the northern Qilian Shan.

A high resolution deep seismic reflection profile of 68.9 km long across the Yinchuan faulted basin has been accomplished which for the first time yields the fine crustal structures, characteristics of deep fault system (Yellow River fault, Yinchuan fault and Eastern piedmont fault of Helanshan) of faulted basin in graben style, and the relationship between shallow and deep structures in Yinchuan basin. The results show that the upper crust is the region above a reflector with 8 s two‐way traveling time (about 20 km deep), there are many strata in the upper part of the upper crust where the continuity of different segment of stratum is good, and there is no obvious layered feature in the lower part of upper crust, where the geological structure is simple. The reflection energy is weak in the lower crust (8~13 s), where reflection events are not obvious. The crust‐mantle transitional zone (around 13 s) below the lower crust consists of a group of reflection sequences that have stronger energy and longer duration (1.5 s), and the thickness is about 4.5 km. Luhuatai fault and Yinchuan fault merge into the Eastern piedmont fault of Helanshan in the depth of 12~12.5 km and 18~19 km, respectively, the Eastern piedmont fault of Helanshan merges into Yellow River fault in the depth of 28~29 km, and Yellow River fault is a deep fault cutting the Moho. Yinchuan graben is a negative flower structure that is assembled mainly by Yellow River fault and secondarily by other faults. Based on the relationship between the Eastern piedmont fault of Helanshan and Yinchuan fault, it is thought that the Eastern piedmont fault of Helanshan played a controlling role in 1739 M=8 Pingluo‐Yinchuan earthquake.

It is known from the research of active tectonics that the northern margin of Tianshan mountains is characterized by typical intra‐continental active tectonics, and has multiple thrust faults and anticlines parallel to the mountains. In order to investigate the fine crustal structure and the geometry of major faults, as well as the deep‐shallow tectonic relations in the Ürümqi depression, a deep seismic reflection profile of 78 km long in near‐SN direction was completed in 2004. This profile is located in the transition zone between Tianshan Mountains and Junggar Basin to the west of Ürüumqi. The results show that the crust beneath the investigated area is divided into upper and lower crusts by a strong reflective zone at about 9~10.5 s TWT. The thicknesses of the upper and lower crusts are about 26~28 and 23~25 km, respectively. There are rich reflective layers and clear structural patterns above 5 s TWT as well as obviously different structural features along the profile. In the southern region of Xishan, the stacked deep seismic reflection section shows a series of EW‐striking thrust anticlines arranged in SN direction as well as a group of faults thrusting from south to north. All of these are influenced by a deep detachment zone. In the Xishan and Wangjiagou area, there is a set of steeply north‐dipping reflective layers and a group of faults slipping along the layers. The northern part of the profile shows the image of a typical sediment basin and its deepest depth is about 10~12 km. Between 6 and 9 s TWT, the stacked deep seismic reflection section shows disordered reflections with comparatively short continuation time and weak energy. These indicate that this part of the crust is evidently possessed of “reflection transparence”. The Moho transition zone occurs at 14~17 s TWT, and the zone thickness is about 9~10 km. In the studied area, the Moho discontinuity gradually deepens from north to south. Its depth is about 50~52 km at the northern segment of the profile and is about 54~55 km near north Tianshan. In the neighborhood of Xishan at the middle profile, the reflections from the boundary between upper and lower crusts as well as the Moho transition zone become misty while the shallow stratums show signs of uplift and fold, which may be related with the compression between Junggar basin and Tianshan mountains.