The slip rate and strong earthquake recurrence interval on the Qianning-Kangding segment of the Xianshuihe fault zone

Abstract ––The Gobi-Altai, Mongolia, includes high mountain ranges that have accommodated the compressional stresses derived from the collision between the Eurasian and Indian Plates. The Gurvan Bogd, which is one of the main mountain ranges in the Gobi-Altai, is a restraining bend along the Bogd sinistral fault. Although surface ruptures did not form near the Artz Bogd during the Mw = 8.1 Gobi-Altai earthquake of 1957, it is still active, as evidenced by a growing topography (i.e., forebergs). Six foreberg ridges have formed in the foreland of the Artz Bogd, which are considered to be the result of surface deformation of alluvial fans due to thrusting. One stream has cut down to expose a foreberg tip, providing the opportunity to explore the slip evolution of the region. Here we map a growing fault structure related to blind thrusting. We identify five faulting events from an analysis of the outcrop and apply optically stimulated luminescence dating to the faulted sedimentary layers, yielding an average slip rate of 0.045 ± 0.007 m/kyr and an earthquake recurrence interval of 5.8 ± 0.5 kyr over the last ~32 kyr. Furthermore, the long-term (~600 kyr) uplift rate of the foreberg is 0.067 ± 0.007 m/kyr, as deduced by dividing the vertical displacement of the alluvial fan surface by the 10Be surface exposure ages of boulders on the fan. The discrepancy (20–30%) between these two deformation rates may be due to the different timescales they cover and an along-strike gradient in slip rate.

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Paleo-earthquake Evidence and Earthquake Recurrence for Düzce Fault, Turkey

10.21203/rs.3.rs-173382/v1 ◽

2021 ◽

Author(s):

Tolga Komut ◽

Ersin Karabudak

Keyword(s):

Probability Distribution ◽

Probability Distributions ◽

Slip Rate ◽

Recurrence Interval ◽

Historical Earthquake ◽

Earthquake Recurrence ◽

Probability Curve ◽

Recurrence Model ◽

Sequential Event ◽

Earthquake Recurrence Interval

Abstract Paleoseismological trenching was performed along the Düzce fault providing some preliminary insight about its seismogenic behavior. Dating was based on radiocarbon analysis of peat samples collected from the trenches and suggested seven earthquakes have occurred since 1740 BC. Integrating date constraints of events exposed in the trenches suggests a periodical earthquake recurrence model. According to a linear sequential event serial that has minimum misfit determined by considering the probability curve limits of the sample dates, the earthquake recurrence interval is between 384 and 460 years (or possibly between AD 394 and 400). A probability curve was also calculated for the date of the last earthquake (1999 Düzce earthquake) considering the probability distributions of sample dates based on the same event serial. This probability-distribution-based method, similarly, predicted that the 1999 Düzce earthquake occurred between 1933–2005 (± 36 years) with a 68 % probability. After this verification. Using this method, it was estimated that the next earthquake along the Düzce fault has a 68 % probability of occurring between 2328–2392. According to this calculation, the earthquake recurrence interval is about 391 ± 34 years with a 68 % probability and the AD 967 historical earthquake likely ruptured the Düzce fault. Assuming an average slip of 350 cm (the average slip of the 1999 earthquake), the slip rate was estimated to be between 8.7–11.2 mm/a.

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Bounds on the Average Recurrence Interval of Major Earthquakes Along the Haiyuan Fault In North-Central China

Seismological Research Letters ◽

10.1785/gssrl.59.3.81 ◽

1988 ◽

Vol 59 (3) ◽

pp. 81-89 ◽

Cited By ~ 20

Author(s):

Zhang Peizhen ◽

Peter Molnar ◽

Zhang Weigi ◽

Deng Qidong ◽

Wang Yipeng ◽

...

Keyword(s):

Slip Rate ◽

Recurrence Interval ◽

Central China ◽

Great Earthquake ◽

Average Amount ◽

Earthquake Recurrence ◽

Surface Rupture ◽

North Central ◽

Recurrence Intervals ◽

Historic Record

Abstract Evidence of surface rupture has been found in trenches near Caiyuan and Shaomayin along the Haiyuan fault, where a great earthquake occurred in 1920. In addition to the 1920 earthquake, faulting occurred at least once between 2590 ± 190 years and 1525 ± 170 years B.P. in Caiyuan, and there probably was another event since 1525 ± 170 years B.P. The formation and later tilting of fault-related, scarp-derived colluvial wedges in the Shaomayin trench appear to record the occurrence of two pre-1920 events in the last 2200–3700 years, but there could have been three or more events. The average recurrence interval for great earthquakes along the Haiyuan fault probably exceeds 700 years, for the 1920 Haiyuan earthquake is the only major event to have been reported in this area in as many years of recorded history. Using a Holocene slip rate along this fault of 8 ± 2 mm/yr, and 8 m as the average amount of offset associated with past great events that have been determined by our previous studies, the resultant earthquake recurrence intervals would be from 800 to 1400 years. The results from our trenches and the historic record are consistent with this range.

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Effects of strong seismic shaking in lake sediments, and earthquake recurrence interval, Témiscaming, Quebec

Canadian Journal of Earth Sciences ◽

10.1139/e91-118 ◽

1991 ◽

Vol 28 (9) ◽

pp. 1349-1352 ◽

Cited By ~ 35

Author(s):

Ronald Doig

Keyword(s):

Relative Frequency ◽

Sediment Cores ◽

Recurrence Interval ◽

Small Lakes ◽

Earthquake Recurrence ◽

Uppermost Layer ◽

Earthquake Recurrence Interval ◽

A Minor ◽

Epicentral Region ◽

Silt Layer

The magnitude 6.3 Timiskaming earthquake of 1935 resulted in discoloration in small lakes in the epicentral region. Sonar profiles for Lac Tee have shown that organic-rich gyttja has been removed from the sides and redeposited in the deep parts of the lake. Lake sediment cores from deep basins contain a 2–3 cm uppermost layer, which is interpreted as the normal accumulation of sediment since 1935. This is followed by a 20 cm chaotic zone of black gyttja mixed with partly tabular fragments of a previously formed silt layer, underlain by a dense 1–2 cm thick silt horizon. The latter is interpreted as having formed by rapid settling of the denser silicate portion of the resuspended sediment. This 20 cm zone is insufficient to account for the abnormal thickness of gyttja in the basins, so events of this kind would have had to have occurred repeatedly since deglaciation. The only major prehistoric event revealed by these ~100 cm cores is at a depth equivalent to about 1500 years ago, based on the amount of sediment deposited since 1935. A minor silting event occurred about 400 years ago. On this basis, the recurrence interval of magnitude 6 or greater earthquakes is longer at Témiscaming than at Charlevoix, Quebec (75 years historically), consistent with the present relative frequency of small earthquakes in these two regions.

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Dynamic Deformation And Fault Locking of The Xianshuihe Fault Zone, Southeastern Tibetan Plateau: Implications For Seismic Hazards

10.21203/rs.3.rs-783486/v1 ◽

2021 ◽

Author(s):

Layue Li ◽

Yanqiang Wu ◽

Yujiang Li ◽

Wei Zhan ◽

Xinzhong Liu

Keyword(s):

Fault Zone ◽

Dynamic Deformation ◽

Slip Rate ◽

Deformation Pattern ◽

Observation Data ◽

Strain Accumulation ◽

Dynamic Adjustment ◽

Strong Earthquakes ◽

Coupling Characteristics ◽

Xianshuihe Fault Zone

Abstract The Xianshuihe Fault Zone is one of the most historically seismically active regions in mainland China. However, the seismicity along this fault zone has been quiescent for the past 40 years, since the Daofu M6.9 earthquake in 1981. Understanding its current deformation patterns and fault coupling characteristics is of great significance to estimate the potential risk of strong earthquakes. In this study, we analyzed the dynamic deformation and fault coupling characteristics along the Xianshuihe Fault Zone using Global Positioning System (GPS) data for 1999–2007 and 2016–2020. The results show that the deformation pattern of the Xianshuihe fault zone underwent a dynamic adjustment after the Wenchuan and Lushan earthquakes, i.e., the maximum shear strain accumulation rates of the Luhuo and Daofu sections significantly decreased from 6.0×10-8/a to 3.2×10-8/a, while that of the southeastern segment (i.e., Kangding and Moxi sections) increased from 4.5×10-8/a to 6.2×10-8/a. Additionally, the slip rate and deformation width of the Xianshuihe Fault Zone also changed during these two periods. Combined with the near-field cross-fault observation data, we suggest that the surrounding strong earthquakes 2008 Wenchuan Mw7.9 and 2013 Lushan Mw6.6 had evident differential impacts on the deformation pattern of the Xianshuihe Fault Zone. The fault-coupling inversion results show that the locking degree of the Xianshuihe Fault Zone continued to increase after the Mw7.9 Wenchuan and Mw6.6 Lushan earthquakes, especially the Qianning and Moxi sections increased significantly, with an average coupling coefficient of greater than 0.9 and left-lateral slip-rate deficits of ~5 mm/a and ~8 mm/a, respectively. In contrast, the locking degree of the Kangding section decreased with almost no slip-rate deficit, which may be due to the partial energy release caused by the Mw5.9 and Mw5.6 Kangding earthquakes in 2014. The analysis of the recent rupture history and strain accumulation characteristics of the Xianshuihe Fault Zone indicates that both the Qianning and Moxi sections have a high seismic potential for the next strong earthquake in the Xianshuihe Fault Zone.

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