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

Abstract

Recurrence interval of large earthquake on an active fault zone is an important parameter in assessing seismic hazard. The 2008 Wenchuan earthquake (Mw 7.9) occurred on the central Longmen Shan fault zone and ruptured the Yingxiu-Beichuan fault (YBF) and the Guanxian-Jiangyou fault (GJF). However, there is a considerable discrepancy among recurrence intervals of large earthquake in preseismic and postseismic estimates based on slip rate and paleoseismologic results. Post-seismic trenches showed that the central Longmen Shan fault zone probably undertakes an event similar to the 2008 quake, suggesting a characteristic earthquake model. In this paper, we use the published seismogenic model of the 2008 earthquake based on Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data and construct a characteristic seismic moment accumulation/release model to estimate recurrence interval of large earthquakes on the central Longmen Shan fault zone. Our results show that the seismogenic zone accommodates a moment rate of (2.7 ± 0.3) × 1017 N m/yr, and a recurrence interval of 3900 ± 400 yrs is necessary for accumulation of strain energy equivalent to the 2008 earthquake. This study provides a preferred interval estimation of large earthquakes for seismic hazard analysis in the Longmen Shan region.

Deep deformation of the Longmenshan fault zone related to the 2008 Wenchuan earthquake

“…谢 富仁等人 [110] 利用地质资料、地震学和大地测量学资 料, 采用3种方法分别计算综合判定的龙门山断裂带 的大震复发间隔: 7.0级地震的500 a左右, 7.5级地震 的1000 a左右, 8.0级地震的3000 a左右. 较为详细的 古地震研究 [111,112] 则表明: 发生汶川地震的北川-映 秀断裂和灌县-江油断裂北川以南段2008年前最近1 次地表破裂型(古)地震发生在距今3300~2300 a之间, 更早的1次发生在距今5920~5730 a之间, 平均复发间 隔约为3000 a. Ren和Zhang [113] 基于GPS和InSAR数据 约束的地震矩率法估算的复发间隔为3900±400 a. 祝 爱玉等人 [114] 对川滇地区的三维黏弹性有限元模拟计 算 得 到 整 个 龙 门 山 断 裂 带 的 8 级 地 震 复 发 间 隔 为 2000~10000 a. Liu等人 [115] 通过对龙门山断裂带岩石 圈的三维有限元黏弹性动力学模拟, 估算的发生类 似汶川地震的强震复发周期为4200~6500 a. Thomp-son等人 [116] 则基于Gan等人 [47] 反演得到的同震破裂滑动量集中区常被解释为 断 层 的 凹 凸 体 (asperities) [25,86,89~92,118] 或 障 碍 体 (barriers) [57,59,94,95] , 就凹凸体的结果来说就明显有2…”

The 2015 M w 6.0 Mt. Kinabalu earthquake: an infrequent fault rupture within the Crocker fault system of East Malaysia

“…Many of Earth's most recent seismic disasters have resulted from the rupture of faults that have recurrence times measured in thousands of years. The average recurrence interval of the Longmenshan Fault that produced the M w 7.9 Wenchuan earthquake in 2008 may well be 3-4 kyear (e.g., Ran et al 2013;Ren and Zhang 2013). The Greendale Fault, which produced the 2010 M w 7.1 Darfield earthquake, has a mean recurrence interval of 10-60 kyear (Hornblow et al 2014).…”

Morphotectonic Evolution of an Alluvial Fan: Results of a Joint Analog and Numerical Modeling Approach

“…The reference return period T re f is equal to 1800 years (Table 1). Except in particular regions with a very low shortening rate (e.g., [43]), the return period of strong earthquakes (M > 7) is generally a few hundred years (e.g., [23,45]). Here, we ran seven models with return periods between 0.05 × T re f and 1.1 × T re f .…”