Trenching exposures of the surface rupture of 2008 Mw 7.9 Wenchuan earthquake, China: Implications for coseismic deformation and paleoseismology along the Central Longmen Shan thrust fault

SAR interferometry and optical remote sensing for analysis of co-seismic deformation, source characteristics and mass wasting pattern of Lushan (China, April 2013) earthquake

“…The LOS displacement pattern shows that for the eastern side of the LFZ, in the south, SE and NE portion of the Sichuan basin under consideration in this study, the deformation has resulted in increased slant range (negative LOS displacement values). Using the information on the co-seismic GPS observations Hua and Guoqiang, 2013), tectonic setting of the Longmenshan fault zone (Zhang et al, 2009;Shen et al, 2005;Li et al, 2011), nature of seismogenic structure (Zhang Yueqiao et al, 2013;XiWei et al, 2013) and the conditions leading to slant range changes as explained in the previous paragraph, we interpret that the negative LOS displacement are resultant of oblique westward subsidence of the Sichuan basin along a westerly dipping plane, steeper than 30 • (far range incidence angle). This condition coincides with case 9 in Fig.…”

Estimation of Recurrence Interval of Large Earthquakes on the Central Longmen Shan Fault Zone Based on Seismic Moment Accumulation/Release Model

“…The ages of radiocarbon dating are younger due to polluted samples by newer carbonaceous matters [2, 44]. The result of Li et al is apparently older than the time span of earthquake record [12]. The reason could be that the OSL samples of colluvium related to the earthquake might not have been bleached sufficiently [45].…”

“…Preseismic trenches at Leigu and Baishuihe towns along the YBF showed that the penultimate event occurred at 13.81–11.77 ka, based on radiocarbon dating [9, 10]. In the same Qingshiping trench, Li et al and Densmore et al suggested the interval of 3830 and 930 yrs, respectively, based on radiocarbon dating along the GJF [10–12]. Many trenches have been excavated across the coseismic surface rupture following the 2008 earthquake (Figure 1).…”

“…The trenches at Yingxiu, Xiaoyudong, Leigu, and Bailu towns using radiocarbon dating showed a recurrence interval of 2300–3300 yrs [14, 15]. The trenches of Li et al at Pingtong, Guixi, and Nanba towns from optically stimulated luminescence (OSL) and radiocarbon dating revealed a ~11000 yr interval [12]. Liu et al advised a recurrence interval of 1100–2100 yrs in the Leigu trench utilizing OSL and radiocarbon dating [16].…”

The 2008 Wenchuan earthquake and active tectonics of Asia

“…Consequently, they suggest that crustal shortening related to repeated great seismic events, together with isostatic rebound induced by rapid erosion-related unloading, is a key component of the geodynamics that drive ongoing mountain building on the eastern Tibetan Plateau. Li et al (2011) report the trenching excavation across the 2008 earthquake rupture across the Yingxiu-Bichuan fault on three representative sites as well as the 14 C and OSL dating data. They suggest that the 2008 earthquake is a characteristic earthquake along the Yingxiu-Beichuan fault.…”