The 2003 Ms6.1 Minle Earthquake: An Earthquake in the Minle-Yongchang Reverse Fault-Related Fold Belt in the Hexi Corridor, NW China

The Minle-Yongchang fault is an active reverse fault-related fold structural belt developed in the Hexi Corridor Basin on the northeastern edge of the Tibetan Plateau. An earthquake of Ms6.1 occurred near the Minle-Yongchang fault zone in 2003. The deformation pattern of the Minle-Yongchang fault and its relationship with this strong earthquake, however, are still not well known. In this study, we used the methods of HYPOINVERSE absolute location and double-difference location with waveform cross-correlation technology to relocate the 2003 Minle earthquake sequence. In total, 383 earthquakes are precisely relocated. Based on the results of precise seismic relocation, using the method of determining fault planes by small earthquakes, the seismogenic fault is found to be a low-angle thrust with a strike of 311°, a dip of NE, and a dip angle of 14°. It does not rupture the surface, extends to 19–20 km depth, and is hidden beneath the Yonggu Anticline. We also employed the cut-and-paste (CAP) method with a broadband waveform to determine the focal mechanism of the mainshock in 2003: the strike is 311°; the dip is 34°; and the rake is 90°. The fault plane parameters obtained in these two ways are roughly consistent. We also used a digital elevation model (DEM) derived from the SPOT 6 stereo image pair and high-precision differential Global Positioning System (GPS) to measure the displacement of terraces. Topographic profiles along the terraces across the Minle-Yongchang fault show that high alluvial terrain exhibits fold deformation. The vertical offsets of the T2 and T3 terraces along the Tongziba River are approximately 2.3 and 22 m, respectively. Optically stimulated luminescence (OSL) dating indicates that the ages of T2 and T3 are 11.3 and 106 ka, respectively. We calculated an average uplift rate of 0.21 ± 0.05 mm/a by dividing the vertical offset by age. According to the spatial distribution of the relocated earthquake sequence and terrace deformation in the study area, the Ms6.1 Minle earthquake in 2003 was caused by the latest activity of a blind reverse fault-related fold in the Hexi Corridor Basin.

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The Alland earthquake sequence in Eastern Austria: Shedding light on tectonic stress geometry in a key area of seismic hazard

Austrian Journal of Earth Sciences ◽

10.17738/ajes.2019.0010 ◽

2019 ◽

Vol 112 (2) ◽

pp. 182-194

Author(s):

Sven Schippkus ◽

Helmut Hausmann ◽

Zacharie Duputel ◽

Götz Bokelmann ◽

_ _

Keyword(s):

Moment Tensor ◽

Earthquake Sequence ◽

Fault System ◽

Double Difference ◽

Reverse Fault ◽

Vienna Basin ◽

Regional Stress ◽

3D Velocity Model ◽

Waveform Cross Correlation ◽

Eastern Austria

AbstractWe present our results on the fault geometry of the Alland earthquake sequence in eastern Austria (Eastern Alps) and discuss its implications for the regional stress regime and active tectonics. The series contains 71 known events with local magnitudes 0.1 ≤ ML ≤ 4.2 that occurred in between 2016 and 2017. We locate the earthquakes in a regional 3D velocity model to find absolute locations. These locations are then refined by relocating all events relative to each other using a double-difference approach, based on relative travel times measured from waveform cross-correlation and catalogue data. We also invert for the moment tensor of the ML = 4.2 mainshock by fitting synthetic waveforms to the recorded seismo-grams using a combination of the L1- and L2-norms of the waveform differences. Direct comparison of waveforms of the largest events in the sequence suggests that all of them ruptured with very similar mechanisms. We find that the sequence ruptured a reverse fault, that is dipping with ~30° towards ~north-northeast (NNE) at 6–7 km depth. This is supported by both the hypocentres and the mainshock source mechanism. The fault is most likely located in the buried basement of the Bohemian massif, the “Bohemian Spur”. This (reverse) fault has a nearly perpendicular orientation to the normal-fault structures of the Vienna Basin Transfer Fault System further east at a shallower depth, indicating a lateral stress decoupling that can also act as a vertical stress decoupling in some places. In the west, earthquakes (at a larger depth within the upper crust) show compressive stresses, whereas the Vienna Basin to the east shows extensional (normal-faulting) stress. This provides insight into the regional stress field and its spatial variation, and it helps to better understand earthquakes in the area, including the “1590 Ried am Riederberg” earthquake.

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Relocation of the February 2016 Mt. Pandan earthquake sequence using double difference with waveform cross correlation

10.1063/1.5047321 ◽

2018 ◽

Author(s):

Renhard Sipayung ◽

Muhamad Rizha Alhafiz ◽

Rezki Agus ◽

Dimas Sianipar

Keyword(s):

Cross Correlation ◽

Earthquake Sequence ◽

Double Difference ◽

Waveform Cross Correlation

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Supplemental Material: Geophysical analysis of the 30 July 1972 Sitka, Alaska, earthquake sequence

10.1130/geos.s.12041772.v2 ◽

2020 ◽

Author(s):

Juan A. Ochoa Chavez ◽

Diane Doser

Keyword(s):

Earthquake Sequence ◽

Double Difference ◽

Alaska Earthquake

Supplemental Material 1 contains relocated aftershocks of 30 July 1972 sequence. Supplemental Material 2 contains relocation parameters used in double-difference algorithm (HYPODD).

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Repeating earthquakes follow afterslip gradient in the aftermath of the 16th April 2016 M7.8 Pedernales earthquake in Ecuador

10.5194/egusphere-egu21-2918 ◽

2021 ◽

Author(s):

Caroline Chalumeau ◽

Keyword(s):

Template Matching ◽

Earthquake Forecasting ◽

Double Difference ◽

Recurrence Time ◽

Fault Mechanics ◽

Aseismic Slip ◽

Earthquake Triggering ◽

Repeating Earthquakes ◽

Waveform Cross Correlation ◽

One Year

Repeating earthquakes are earthquakes that repeatedly break a single, time-invariant fault patch. They are generally associated with aseismic slip, which is thought to load asperities, leading to repeated rupture. Repeating earthquakes are therefore useful tools to study aseismic slip and fault mechanics, with possible applications to earthquake triggering, loading rates and earthquake forecasting.In this study, we analyze one year of aftershocks following the 16th April 2016 Mw 7.8 Pedernales earthquake in Ecuador to find repeating families, using data recorded by permanent and temporary seismological stations. In our area, seismicity during both the inter-seismic and post-seismic periods has been previously linked to aseismic slip. We calculate waveform cross-correlation coefficients (CC) on all available catalogue events, which we use to sort events into preliminary families, using a minimum CC of 0.95. These events were then stacked and used to perform template-matching on the continuous data. In total, 376 earthquakes were classified into 62 families of 4 to 15 earthquakes, including 8 from the one-year period before the mainshock. We later relocated these earthquakes using a double-difference method, which confirmed that most of them did have overlapping sources.Repeating earthquakes seem to concentrate largely around the areas of largest afterslip release, where afterslip gradient is the highest. We also find an increase in the recurrence time of repeating events with time after the mainshock, over the first year of the postseismic period, which highlights a possible timeframe for the afterslip&#8217;s deceleration. Our results suggest that while most repeating aftershocks are linked to afterslip release, the afterslip gradient may play a bigger role in determining their location than previously thought.

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Passive seismic tomography using recorded microseismicity: Application to mining-induced seismicity

Geophysics ◽

10.1190/geo2018-0076.1 ◽

2019 ◽

Vol 84 (1) ◽

pp. B41-B57 ◽

Cited By ~ 4

Author(s):

Himanshu Barthwal ◽

Mirko van der Baan

Keyword(s):

Seismic Tomography ◽

Velocity Model ◽

P Wave ◽

Double Difference ◽

Lateral Velocity ◽

Study Region ◽

Arrival Times ◽

3D Velocity Model ◽

Passive Seismic ◽

Dip Angle

Microseismicity is recorded during an underground mine development by a network of seven boreholes. After an initial preprocessing, 488 events are identified with a minimum of 12 P-wave arrival-time picks per event. We have developed a three-step approach for P-wave passive seismic tomography: (1) a probabilistic grid search algorithm for locating the events, (2) joint inversion for a 1D velocity model and event locations using absolute arrival times, and (3) double-difference tomography using reliable differential arrival times obtained from waveform crosscorrelation. The originally diffusive microseismic-event cloud tightens after tomography between depths of 0.45 and 0.5 km toward the center of the tunnel network. The geometry of the event clusters suggests occurrence on a planar geologic fault. The best-fitting plane has a strike of 164.7° north and dip angle of 55.0° toward the west. The study region has known faults striking in the north-northwest–south-southeast direction with a dip angle of 60°, but the relocated event clusters do not fall along any mapped fault. Based on the cluster geometry and the waveform similarity, we hypothesize that the microseismic events occur due to slips along an unmapped fault facilitated by the mining activity. The 3D velocity model we obtained from double-difference tomography indicates lateral velocity contrasts between depths of 0.4 and 0.5 km. We interpret the lateral velocity contrasts in terms of the altered rock types due to ore deposition. The known geotechnical zones in the mine indicate a good correlation with the inverted velocities. Thus, we conclude that passive seismic tomography using microseismic data could provide information beyond the excavation damaged zones and can act as an effective tool to complement geotechnical evaluations.

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Dynamic Rupture Simulations of the 1920 Ms 8.5 Haiyuan Earthquake in China

Bulletin of the Seismological Society of America ◽

10.1785/0120190061 ◽

2019 ◽

Vol 109 (5) ◽

pp. 2009-2020 ◽

Cited By ~ 1

Author(s):

Xiurong Xu ◽

Zhenguo Zhang ◽

Feng Hu ◽

Xiaofei Chen

Keyword(s):

Ground Motion ◽

Intensity Distribution ◽

Strong Ground Motion ◽

Ground Surface ◽

Peak Ground Velocity ◽

The Tibetan Plateau ◽

Dynamic Rupture ◽

Seismogenic Fault ◽

Maximum Displacement ◽

Strong Ground

Abstract The Haiyuan fault is a major seismogenic fault on the northeastern edge of the Tibetan–Qinghai plateau. The 16 December 1920 Ms 8.5 Haiyuan, China, earthquake is the largest and most recent event along the eastern Haiyuan fault (the Haiyuan fault in the article). Because only a few near‐field seismic recordings are available, the rupture process remains unclear. To understand the source process and intensity distribution of the 1920 Haiyuan earthquake, we simulated the dynamic rupture and strong ground motion of said earthquake using the 3D curved‐grid finite‐difference method. Considering the differences in epicenter locations among various catalogs, we constructed two models with different source points. For each model, three versions with different fault geometries were investigated: one continuous fault model and two discontinuous fault models with different stepover widths (1.8 and 2.5 km, respectively). A dynamic rupture source model with a final slip distribution similar to that observed on the ground surface was found. The maximum displacement on the ground surface was ∼6.5 m. Based on the dynamic rupture model, we also simulated the strong ground motion and estimated the theoretical intensity distribution. The maximum value of the horizontal peak ground velocity occurs near Haiyuan County, where the intensity reaches XI. Without considering the site conditions, the intensity values in most regions, based on the dynamic scenarios, are smaller than the values from field investigation. In this work, we present physically based insights into the 1920 Haiyuan earthquake, which is important for understanding rupture processes and preventing seismic hazards on the northeastern boundary of the Tibetan plateau.

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Rupture process of the July 2003 northern Miyagi earthquake sequence, NE Japan, estimated from double-difference hypocenter locations

Earth Planets and Space ◽

10.1186/bf03352483 ◽

2003 ◽

Vol 55 (12) ◽

pp. 741-750 ◽

Cited By ~ 22

Author(s):

Tomomi Okada ◽

Norihito Umino ◽

Akira Hasegawa

Keyword(s):

Rupture Process ◽

Earthquake Sequence ◽

Double Difference ◽

Ne Japan

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Slowly migrating tectonic microearthquake swarms in the Icelandic Rift Zone: driven by pore-pressure or aseismic slip transients?

10.5194/egusphere-egu2020-19827 ◽

2020 ◽

Author(s):

Tom Winder ◽

Robert S. White

Keyword(s):

High Resolution ◽

Rift Zone ◽

Double Difference ◽

Aseismic Slip ◽

Tectonic Earthquake ◽

Scaling Properties ◽

Waveform Cross Correlation ◽

Modelling Studies ◽

Event Times ◽

Seismic Moment Release

Swarms of microearthquakes on a network of conjugate strike-slip faults in the rift zone in Central Iceland have been detected and located using a dense local seismic network operational since 2007. These swarms have been recorded since the 1970s, but the cause of their clear swarm-like nature remains enigmatic.We use the QuakeMigrate earthquake detection and location software &#8211; which is able to detect earthquakes separated by very small inter-event times &#8211; to produce a highly complete catalogue. Automatic hypocentre locations have been refined using waveform cross-correlation and double-difference relocation, and focal mechanisms and manual earthquake locations have been produced for a subset of events by manual picking. Analysis of the resulting high-resolution earthquake catalogue reveals systematic migration of hypocentres at velocities of ~ 1 km/day along sharply defined fault planes ranging from 1 &#8211; 10 km in length. In the majority of swarms we also observe clusters of identical repeating events, providing evidence for re-loading of the brittle asperities that produce earthquakes.For a selection of swarms, our high resolution seismic observations are complemented by GPS and InSAR measurements, allowing us to constrain the amount of fault slip. Comparing this, and the area of the fault plane activated in the swarm, to the seismic moment release reveals a significant contribution of aseismic slip, or very low effective stress drop. Analysis of swarms triggered on these faults by the static coulomb stress increase induced by the 2014 B&#225;r&#240;arbunga-Holuhraun dike intrusion provides a further estimate of the amplitude of the stress cycle.We combine our observations with comparisons to numerical & laboratory modelling studies, observed swarm scaling properties and knowledge of the geological and permeability structure of the Icelandic crust to determine the nature of the transient forcing driving these exceptionally well-recorded tectonic earthquake swarms.

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The Application and Research of the Double Difference Method about Regional and Telseismic Earthquake

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.622-623.1651 ◽

2012 ◽

Vol 622-623 ◽

pp. 1651-1654

Author(s):

Ba Teer Wu ◽

Er Gen Gao ◽

Ye Wu

Keyword(s):

Travel Time ◽

Basic Principle ◽

Difference Method ◽

Earthquake Sequence ◽

Double Difference ◽

Earth Model

The paper rests on the basic principle of the double difference method, through using Kennett and Engdahl(1991)’s IASPEI Earth model which can be used in computation theoretical travel time in the condition of regional and telseismic earthquake .We have developed a double difference program which can be used in the regional and teleseismic earthquake. And utilizes this program to relocate the Jiashi Ms 6.8 earthquake sequence in Xinjiang province on 24/2/2,003, obtained a quite good result.

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