Theoretical and quantitative analyses of the fault slip rate uncertainties from single event and erosion of the accumulated offset
Theoretical and quantitative analyses of the fault slip rate uncertainties from single event and erosion of the accumulated offset
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单次事件和累积偏移量侵蚀引起的断层滑移率不确定性的理论和定量分析
DOI：
10.1111/iar.12015
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发表时间：
2013-06
期刊：
影响因子：
1.5
通讯作者：
Wang, Weitao
中科院分区：
文献类型：
--
作者：
Ren, Zhikun;Zhang, Zhuqi;Chen, Tao;Wang, Weitao
断层滑动率是活动构造学研究的重要指标之一，它反映了断层的活动性和地震潜力。随着测年方法的发展，测年精度不断提高，全新世地质标志，甚至数千年或数百年的年轻标志，被广泛应用于断层滑动率的计算。通常，在确定断层滑动率时，涉及到单个事件的不确定性和累积偏移量的侵蚀。两种类型的不确定性与单一事件有关；第一个是最近（最近）事件发生后经过的时间；二是从地质标志形成到第一次事件发生的时期。高滑动率断层比低滑动率断层对这些不确定性更敏感。本文采用特征地震、均匀滑动和变滑动三种经典地震模型，定量研究了单次地震对断层滑动率的影响。我们建议在断层滑动估计中也应考虑走滑断层上累积偏移侧向侵蚀的侵蚀。因此，我们提出了一种差分方法来获得可靠的断层滑动率。在微分法中，滑移率是沿走滑断层的较老和较年轻梯田的偏置差值与相应的年龄差值之比。这种微分方法可以避免最初和最近事件的不确定性，以及侧向侵蚀的不确定性。应用差分方法，得到阿尔金断裂带和昆仑断裂带的修正滑动速率为~ 5 ~ 10 mm/年。这些低滑动率可以与以前的大地测量和地质断层滑动率和缩短率以及沿这些断层主要段的强震千年复发间隔相吻合。
Fault slip rate is one of the most important subjects in active tectonics research, which reveals the activity and seismic potential of a fault. Due to the improvement of dating precision with the development of dating methods, Holocene geological markers, even the young markers of thousands or hundreds of years old, are widely used in fault slip rate calculation. Usually, uncertainties from a single event and erosion of the accumulated offsets are involved in fault slip rate determination. Two types of uncertainties are related to a single event; the first is the time elapsed since the latest (the most recent) event; the second is the period since the formation of the geological marker to the occurrence of the first event. High‐slip‐rate faults are more sensitive to these uncertainties than low‐slip‐rate faults. In this study, we studied quantitatively the effects of a single event on fault slip rate following the three classic earthquake models: the characteristic earthquake, uniform slip and variable slip models. We suggest that the erosion of the accumulated offset–lateral erosion on a strike‐slip fault, should also be considered in fault slip estimation. Therefore, we propose a differential method to obtain a reliable fault slip rate. In the differential method, the slip rate is the ratio of offset differentials and corresponding age differentials between the older and younger terraces along strike‐slip faults. This kind of differential method could avoid the uncertainties from the first and latest events, as well as that from the lateral erosion. By applying the differential method, we got the revised slip rates of ∼5–10 mm/year on the Altyn Tagh and Kunlun faults. These low slip rates could fit previous geodetic and geological fault slip rates and shortening rates as well as the millennial recurrence intervals of strong earthquakes along the major segments of these faults.
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DOI：
10.5860/choice.28-1579
发表时间：
2016
期刊：
--
影响因子：
--
作者：
Leon Bieber
通讯作者：
Leon Bieber
影响因子：
5.8
作者：
Daniel C. Pope;S. Willett
通讯作者：
Daniel C. Pope;S. Willett
影响因子：
5.8
作者：
A. Draut;P. Clift
通讯作者：
A. Draut;P. Clift
影响因子：
4.2
作者：
Peizhen Zhang;P. Molnar;Xi-wei Xu
通讯作者：
Peizhen Zhang;P. Molnar;Xi-wei Xu
DOI：
10.1146/annurev.ea.14.050186.001053
发表时间：
1986
影响因子：
14.9
作者：
R. Sibson
通讯作者：
R. Sibson