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The liquefaction that occurred in the city of Palu on September 28, 2018, was caused by a series of significant earthquakes that took place in a relatively short time around 25 minutes after the main earthquake of magnitude 7.5. This event was followed by aftershocks of magnitudes 6.4, 6.2, and 6.1. The magnitude 6.2 aftershock occurred at 10.16 UTC, while the magnitude 6.1 aftershock occurred at 10.25 UTC. These were both located very close to the liquefaction locations in Balaroa, Petobo, and Jono Oge. We investigated the mainshock and the three aftershocks using the NCEER method based on Vs30 measurements and data from the drill liquefaction locations at Balaroa, Petobo, and Jono Oge. We found that the liquefaction was not only caused by the main earthquake but also by the subsequent aftershocks that occurred within 25 minutes after the mainshock. [ABSTRACT FROM AUTHOR]

The existence of aftershocks in an earthquake sequence can impact the analysis of the mainshock. In this study, we present a method for deleting an aftershock sequence based on the spatial relationship between earthquakes and faults. This method improves the performance of space window selection in the classical K-K method by eliminating aftershocks with an ideal fault buffer zone. The determination of fault buffer zones is based on a trial-and-error analysis of 69,714 earthquake records from the China Seismic Network Center (CENC) collected between 1980 and 2020. We selected 20 typical big earthquakes ( M L 7.0–8.0 or ~ M s 6.6–8.0; for earthquakes above magnitude M s 7 or M L 7.2 , M L is approximately equal to M s ) as the mainshocks to establish the fault buffer zones. We also propose an empirical formula to determine the distance of the fault buffer zone by counting the aftershock deletion effect at different buffer distances. Compared with the classical K-K method, our method considers the correlation between the spatial distribution of aftershocks and faults, eliminates earthquake groups that are not related to the mainshock, greatly reduces the spatial range of aftershocks, improves the performance of deleting aftershocks of different magnitudes, and provides a new rule and reference for aftershock deletion. [ABSTRACT FROM AUTHOR]

Through the study of the real seismic behavior, we find that large mainshocks are often followed by aftershocks. Mainshocks occur instantaneously, while aftershocks feature relatively slow relaxation. Based on the Olami–Feder–Christensen with relaxation (OFCR) model, the long-range interactions and new energy distribution rule are added into our model. At the same time, we find that the statistical distributions of seismic magnitude, and time intervals of mainshock and aftershock conform to the power law behaviors. By comparing the curves of aftershock and mainshock behaviors, we find that they have similar distribution characteristics, which indicates that the study of aftershock behavior is of practical significance for the study of large earthquakes. Meanwhile long-range interactions OFCR model can provide a good supplement for the large earthquake data. [ABSTRACT FROM AUTHOR]

The 28 April 2021 earthquake Mw 6.1 (epicentre 26.69° N, 92.36° E; centroid depth ~ 40 km GCMT report, www.globalcmt.org) in the Sonitpur district of Assam valley, North East (NE) India occurred at the Kopili fault (KF) zone, a long transverse structure across the valley. The earthquake caused a few casualties and injuries and some damage to buildings, ground fractures, fountains and liquefactions, landslides and other such manifestations in several parts of the valley, with a maximum intensity of MMI VI. The KF is identified as a seismically most active fault that caused two (1869 and 1943) large earthquakes (Mw > 7.0) in the past and several severely felt earthquakes (Mw ≥ 5.0) in recent years. Fault plane solutions of the 28 April 2021 mainshock and six aftershocks (Mw > 3.5) are determined by waveform inversion using broadband seismograms of the nearest observatory at Tezpur. The solutions are comparable to the GCMT solution of the mainshock and correlated with the known right-lateral strike-slip motion at the KF zone. The low-stress drops of the earthquake sequence indicate relatively long source duration and small co-seismic slip of the mainshock and the aftershocks. The low-stress drop in terms of lower energy release may be due to reactivation of the KF. The low-stress drop also indicates a pre-existing fault zone at greater depth. A stress inversion analysis of the 17 available fault plane solutions indicates a NNE–SSW compressional and NNW–SSE tensional stress regime in the KF zone. The Coulomb stress change map, on the other hand, identifies the zone of triggered aftershocks. [ABSTRACT FROM AUTHOR]

The Kachchh Rift Basin (KRB) is a very peculiar region in the Indian subcontinent mostly due to the intense seismic activity and intricate tectonics that is located far from the active plate boundaries. The KRB region is located in the Deccan Volcanic Province of Western India. Recently, a moderate earthquake (Mw5.3) occurred in this region on June 14, 2020, that was followed by ~ 22 earthquakes (M ≤ 4.6) until June 23, 2020. This moderate-size event falls about 12 km SSE from the 2001 Bhuj earthquake (Mw7.6). The mainshock and aftershocks are found to be located in an area of ~ 20 × 20 km2 that is orienting NE-SW indicating the rupture area of the mainshock. Several pertinent questions arose for the recent moderate event as it was located in the vicinity of the 2001 mainshock. The estimated focal mechanism solution of the current event depicts reverse faulting with a small strike-slip component. The current seismic activity matches well with the south-dipping nodal plane that is akin to the South Wagad Fault (SWF) in the region. The Coulomb failure stress change (∆CFS) caused due to the 2020 mainshock, considering the source as a receiver fault, clearly demonstrates the locations of aftershocks in the zone of compression that corroborates well with the south-dipping source. Such a strong correlation between the static stress changes and the aftershocks indicated SWF as the causative source. Interestingly, we found that the recent earthquake sequence has occurred in the shadow zone of the 2001 Bhuj mainshock. The coseismic deformation due to the 2020 mainshock was also obtained using an InSAR interferogram that demonstrated coseismic subsidence of ~ 3.6 cm close to the source zone, which is found to be consistent with the activity along with the south-dipping SWF. In addition, the low seismic velocities (Vp, Vs), high Vp/Vs ratio, and positive Coulomb stress changes suggest entrapped magma fluid in the seismogenic rock matrix, which probably played a significant role in triggering earthquakes in the study region. We validated our observations with the earlier seismological, geophysical, and geological shreds of evidence. [ABSTRACT FROM AUTHOR]

This paper aims to evaluate the vertical-to-horizontal, V/H, spectral acceleration ratios from the earthquake ground motions recorded during the February 6, 2023 Turkey-Syria seismic events, which include doublet events with moment magnitudes of M w 7.7 and M w 7.6 that struck the city of Kahramanmaraş and a considerable aftershock with M w 6.7 that mainly struck the city of Nurdağı. Statistics of the observed V/H spectral ratios computed from records that have peak ground acceleration larger than 0.1 g showed that most records of the three earthquakes yielded spectral V/H ratios higher than 2/3, which is a typical value recommended by several seismic codes. Additionally, comparison of the observed V/H spectra with respect to the Ground Motion Predictive Models, GMPMs, for V/H ratios introduced by Bozorgnia and Campbell (2016), BC model, and Bommer et al. (2011), BAK model, revealed that both GMPMs mostly underestimate the V/H ratios at long spectral periods. Residual analysis showed that the capability of the BAK model for large source-to-site distances is more than that for small distances for which the ratios may be underestimated specially at long periods, while the estimations of the BC model do not significantly depend on the distance. Additionally, comparison of the observed V/H ratios with those computed based on the current 2018 edition of the Turkish seismic code indicated that the three considered earthquakes mostly yielded V/H ratios considerably higher than the code-based values in the long period range that could have higher damaging potential than those ratios in short period range. • Evaluation of the spectral vertical-to-horizontal, V/H, during the 2023 Turkey-Syria seismic events. • V/H spectra based on GMPMs and the Turkish seismic code. • Evaluation of the predictive equations using residuals analysis. [ABSTRACT FROM AUTHOR]

A sequence of main and aftershocks is a complex natural hazard, which may introduce severe damage to critical infrastructure systems. Managing the risk caused by sequential earthquake events is challenging due to the uncertainties of aftershocks and their dependency on the preceding mainshock. Moreover, the dynamic behavior of a structural system under aftershocks must be evaluated with consideration of possible structural damage caused by the mainshock. To overcome these difficulties, this paper proposes a new framework based on a Bayesian network (BN) for risk modelling and inference for structures under a sequence of main and aftershocks. The stochastic mechanisms of sequential earthquakes and the hysteretic behavior of structures are described by BN models, which are then integrated for comprehensive modeling of the risk. The developed BN model facilitates probabilistic inference to obtain fragility curves given various circumstances regarding sequential earthquake events and observations. Numerical examples demonstrate fragility assessment and inference with the proposed BN‐based framework. [ABSTRACT FROM AUTHOR]

This research attempts to propose a new simulating model capable of generating synthetic stochastic earthquake scenario including both seismological, and acceleration signal properties. The Iranian plateau is selected as a mainland for developing the model due to the existence of high-quality earthquake databases. This model is composed of two sub-models. The first one generates random seismic event scenarios including mainshocks and aftershocks. The second one procreates 3-dimensional synthetic stochastic accelerograms for each of the previously simulated events. This scenario-based predictive model offers a powerful tool to the risk modelers interested in lifetime seismic risk assessment through more realistic earthquake scenarios. [ABSTRACT FROM AUTHOR]

One of the efficient methods for seismic design of structures is Performance-based Plastic Design (PBPD) in which by choosing the desired yield mechanism and the target drift at the beginning of the design, unlike that in conventional design methods, there is no need for a time-consuming process of trial and error to achieve the desired performance. On the other hand, recent earthquakes have shown that aftershocks can increase the damage to a building after the main earthquake and thereby threaten the safety of the inhabitants. However, the seismic hazard of aftershocks is still not explicitly included in the current design codes. In this study, attempts have been made to develop the PBPD method for considering the effects of aftershocks. For this purpose, by performing an incremental dynamic analysis (IDA), the ductility factor μ and the ductility reduction factor Rμ of six PBPD frames (2-, 4-, 6-, 8-, 10-, and 12-story) were calculated under mainshock and mainshock-aftershock sequences. Then, the energy modification factor γ, which is related to the two parameters μ and Rμ, was calculated for both the mainshock and the mainshock-aftershock sequences. An equation is presented in order to calculate the ratio of the energy modification factor of the mainshock-aftershock sequence to the mainshock energy modification factor ( γ m s + a s γ m s ) according to the design period, and the factor obtained is multiplied by the energy modification factor γ so that the effect of aftershock can be considered for the frame design, and by using this modification, the performance of the frame under the mainshock-aftershock sequence can be improved. The results of the time-history analysis performed on the modified PBPD frames show better performance by the frames designed on the basis of modified PBPD than the frames designed on the basis of the original PBPD method under MS-AS sequences in terms of inter-story drift and rotation of plastic hinges. [ABSTRACT FROM AUTHOR]

Purpose: This study investigates the seismic performance of vertical irregular steel moment-resisting frames subjected to mainshock–aftershock (MS–AS) seismic sequence. The building structures situated in a seismically active region experience sequence of earthquakes during their lifetime. These seismic sequences have the potential to increase the damage state of the structures. The irregular building structures are present due to availability of space, functional and architectural requirements etc. behave differently as compared to the regular buildings during earthquakes. Methods: In this paper, three steel-moment resisting frames having different configuration i.e. 3, 6, and 9-storey were considered as a reference regular frame. Three vertical irregularities-stiffness, strength and combined stiffness and strength are introduced in three different locations (bottom, mid-height, and topmost storey) along the height of each building frames. These regular and vertically irregular frames are subjected to mainshocks alone and artificial MS–AS seismic sequences that are generated by using the repeated and randomized approach. The nonlinear time-history analysis is performed using computer software SAP 2000 on regular and irregular building frames subjected to mainshocks and MS–AS seismic sequence. Results: The comparison between the seismic performance of vertically irregular and regular frames subjected to mainshocks alone and MS–AS seismic sequences shows that the vertical irregular frames have a significant effect on the distribution of mean interstorey drift demands along the height of building frames. Conclusion: The effect of MS–AS seismic sequence on seismic demands of vertical irregular and regular frames have been increased compared to mainshocks. However, the repeated seismic sequences show smaller structural responses relative to the randomized seismic sequences. [ABSTRACT FROM AUTHOR]

This study comprehensively investigates the source mechanisms associated with the mainshock and aftershocks of the Mw = 6.3 Yogyakarta earthquake which occurred on May 27, 2006. The process involved using moment tensor inversion to determine the fault plane parameters and joint inversion which were further applied to understand the spatial and temporal slip distributions during the earthquake. Moreover, coseismal slip distribution was overlaid with the relocated aftershock distribution to determine the stress field variations around the tectonic area. Meanwhile, the moment tensor inversion made use of near-field data and its Green's function was calculated using the extended reflectivity method while the joint inversion used near-field and teleseismic body wave data which were computed using the Kikuchi and Kanamori methods. These data were filtered through a trial-and-error method using a bandpass filter with frequency pairs and velocity models from several previous studies. Furthermore, the Akaike Bayesian Information Criterion (ABIC) method was applied to obtain more stable inversion results and different fault types were discovered. Strike–slip and dip-normal were recorded for the mainshock and similar types were recorded for the 8th aftershock while the 9th and 16th June were strike slips. However, the fault slip distribution from the joint inversion showed two asperities. The maximum slip was 0.78 m with the first asperity observed at 10 km south/north of the mainshock hypocenter. The source parameters discovered include total seismic moment M0 = 0.4311E + 19 (Nm) or Mw = 6.4 with a depth of 12 km and a duration of 28 s. The slip distribution overlaid with the aftershock distribution showed the tendency of the aftershock to occur around the asperities zone while a normal oblique focus mechanism was found using the joint inversion. [ABSTRACT FROM AUTHOR]

In this paper, a comprehensive accelerogram database of the Iranian plateau containing 3585 data with all three components is gathered. The raw data are processed by the wavelet-based denoising method, and results are compared with the contaminated data. All the data are classified into mainshock and aftershock categories using the time and spatial window method. Afterward, the data are categorized into the pulse-like and non-pulse-like events based on the detection of velocity pulse in any of horizontal and/or vertical directions. Eventually, among 3585 data, the ones with an average shear wave velocity of top 30 m of subsurface soil profile are selected and their important ground motion parameters such as peak ground acceleration, velocity, and displacement, Arias intensity, ground motion duration, and acceleration response spectra are studied. It is observed that the intensity of vertical component of the accelerograms is almost at the same level as the strong horizontal direction or even more, in some cases. Near-field events cause more severe responses than far-field earthquakes. Generally, the mainshocks responses are slightly tougher than the aftershocks. By comparing the acceleration response spectra of the accelerograms with the ones obtained from the building design codes, the necessity of revising the existing standard spectra is revealed for considering the effects of mainshocks, aftershocks, near-field effects, as well as separate vertical component of the ground motions directly. Finally, the presented database, as a powerful tool, will give an interesting opportunity to the scientists and engineers who are enthusiastic to work on the Iranian plateau accelerograms. [ABSTRACT FROM AUTHOR]

With the vast amounts of data recorded by the CWB seismic networks, a fast and precise algorithm for near real-time earthquake locations as well as fundamentally urgent source and hazard studies of large damaging earthquakes in Taiwan becomes increasingly important. Here we present a novel method for automatic phase identification and event detection, modified from a Python-based PhasePApy package to be more computationally efficient and suitable for the high-rate seismicity and large-scale dense network in Taiwan. The performance efficiency is enhanced by substituting the Python code with a Fortran subroutine to calculate the characteristic function for phase picker. It is further improved by amalgamating the picks close enough in time but on different components, associating pairs of the amalgamated picks with the origin times of candidate events through an empirical linear relation between the P and S-P times reported in the CWB phase catalog, and isolating clustered candidate events and corresponding phase picks to determine the locations of real earthquakes. The algorithm is applied to detecting in almost real time over two thousands of events that occurred within four days accompanying the 4 February 2018 ML 5.89 foreshock and 6 February 2018 ML 6.25 Hualien mainshock, which far surpasses the capability of experienced human analysts. The temporal and spatial distributions of the detected aftershocks provide the timely and first-hand information to estimate the aftershock decay rate and verify the orientation of the fault plane and rupture extent of the foreshock and disastrous mainshock as a guide for fast risk assessment and source characteristics analysis. [ABSTRACT FROM AUTHOR]

Knowledge of what governs the interaction between slow‐ and fast‐slip earthquakes is essential to understanding the nature of the earthquake cycle. In southern Taiwan, four major earthquakes (2008 Mw 5.2 Taoyuan, 2010 Mw 6.4 Jiashian, 2012 Mw 5.9 Wutai, and 2016 Mw 6.4 Meinong events) that occurred near the active tremor areas provide a unique opportunity to analyze their spatiotemporal association. With the declustered tremor catalog built in this study, we were able to statistically evaluate the possible association between tremor and mainshock‐aftershock sequences in space and time. We found that close‐by mainshocks influences tremor's timing in a matter of less than 5 days by short‐term triggering, while the 2010 ML 6.4 Jiashian earthquake appears to be most responsible for such triggering. Assuming a low dip angle thrust faulting mechanism, tremors coincided with small static stress increases (8 kPa) in the 2010 ML 6.4 Jiashian earthquake. The other three major events, however, caused either negative or neglectable stress changes in the tremor zone. The different responses of the tremors can be explained by coseismic slip‐induced static stress change. In this complex tectonic region as a boundary between continental subduction and collision, the interaction between slow‐ and fast‐slip phenomena could be facilitated by a commonly high fluid pressure environment. Key Points: We explore the spatiotemporal association between tremors and earthquakes using 7‐year tremor and earthquake catalogIn a confined distance of 5 km, a greater percentage of earthquakes tend to occur in 5 days prior to the tremorsA commonly high fluid pressure environment may be needed, to facilitate their interaction [ABSTRACT FROM AUTHOR]

The present research focuses on the statistical evaluation of Iranian plateau aftershocks from an engineering perspective and presents probabilistic models applicable for generating random earthquake scenarios. Accordingly, a comprehensive earthquake data catalog including the period from 1964 to 2016 is prepared. Data are declustered into 37 separate mainshock-aftershock sequences by considering the completeness moment magnitude of the database. The well-known modified Omori occurrence rate formula is adopted to determine the recurrence time of the events, considering the effect of secondary aftershocks. In addition to computing the probability density functions of the parameters of the Omori formula, the joint probability distribution of the aftershock occurrence versus magnitude and occurrence time is obtained for modeling their magnitude sequences. The obtained results are applicable for producing randomly generated mainshock-aftershock scenarios. [ABSTRACT FROM AUTHOR]

Recent research has shown that for the larger earthquakes recorded (M ≥ 5.2) within the global centroid moment tensor (gCMT) there is a positive correlation between the magnitudes of earthquakes and the magnitudes of their aftershocks [13]. Through a modification of model independent stochastic de-clustering [12] and a more localized catalog provided by the Southern California Earthquake Data Center (SCEDC), the methodologies of Nichols and Schoenberg can be extended to catalogs complete with a much lower minimum magnitude of completeness (M ≥ 2.2). Results indicate that the positive correlation observed between larger earthquakes in the gCMT catalog and their aftershocks is also evident in the relationship between the magnitudes of earthquakes in the SCEDC data and their aftershocks. However, with the lower minimum magnitude of completeness found in the SCEDC catalog and with short periods of extreme earthquake activity evident within the data, the statistical power of the stochastic de-clustering algorithms to distinguish between mainshocks and aftershocks is diminished. [ABSTRACT FROM AUTHOR]

The 2016 Kumamoto earthquake sequence was a rare event worldwide in that the surface ruptures associated with the largest foreshock (Mj 6.5) of 21:26 (JST), 14 April ruptured again during the mainshock (Mj 7.3) of 01:25 (JST), 16 April. The 14 April Mj 6.5 earthquake produced 6-km-long surface ruptures along the central portion of the Futagawa-Hinagu fault zone (FHFZ). The mainshock produced 31-km-long surface ruptures along the central to northeastern part of the FHFZ. Field observations and eyewitness accounts documented that the offsets of the ruptures associated with the 14 April foreshock became larger after the 16 April mainshock, suggesting that the same portion of the fault ruptured to the surface twice in the Kumamoto earthquake sequence. The 6-km-long surface ruptures associated with the largest foreshock are located near a geometric bend of the FHFZ characterized by ~50° change in strike. The epicenter of the mainshock is also located near the bend. These observations imply that the Kumamoto earthquake sequence was initiated due to a stress concentration on the bend of the FHFZ, and the mainshock was initiated approximately at the same place about 28 h after the largest foreshock. This foreshock/mainshock sequence of the Kumamoto earthquake is not successive events on the adjacent different fault zones, because the 6-km-long surface ruptures of the largest foreshock are part of the 31-km-long surface ruptures of the mainshock. [ABSTRACT FROM AUTHOR]

The characteristics of sources of the Gorkha earthquake's mainshock (April 25, 2015, Nepal) and strongest aftershock are given. Macroseismic data and examples of seismic dislocations are provided. The course of seismic energy release during the aftershock process is analyzed. The data on seismological precursors of the mainshock and the strongest aftershock of May 12, 2015, are presented, which allowed the aftershock to be predicted in a short-term interval. [ABSTRACT FROM AUTHOR]

Current assumptions on the level of inter-dependency between the magnitudes of earthquakes and the magnitudes of their aftershocks vary significantly, ranging from assumed independence for models like epidemic type aftershock-sequence (ETAS) to assumed positive correlation, at least for the events leading up to the largest earthquakes, for models like accelerated moment release. Recently, a method was developed by Marsan and Lengline for model independent stochastic de-clustering (MISD) of a multidimensional Hawkes self-exciting process, or as is the case here, earthquake activity. After expanding the algorithm to allow for a spatially dependent background rate (henceforth SDMISD), repeated application of SDMISD to a global earthquake catalog allows for estimates with confidence bounds for the average magnitude of an aftershock conditioned upon the magnitude(s) of the earthquake(s) that caused the aftershock. 15 years of data on M 5.3 earthquakes from the global Centroid Moment Tensor earthquake catalog indicate that the magnitudes of aftershocks are dependent on the magnitudes of the earthquakes that cause them, and indeed, larger than average earthquakes are more likely to trigger larger than average aftershocks. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A destructive earthquake (Mw 6.1) struck East Java, Indonesia, on 10 April 2021, resulting in at least 10 deaths and damage to over 3000 buildings. Preliminary hypocenter determinations indicate that it was located ~20 km south of Java, at a depth of ~60 km, suggesting that it likely occurred within the subducting oceanic slab beneath the Sunda Arc. In order to better understand the origins of this important event, we have undertaken non-linear hypocenter determination of the mainshock and its aftershocks through picking of P- and S-wave arrival times recorded by nearby BMKG seismic stations, followed by precise relative relocation using the double-difference method. We have also conducted source mechanism analysis to determine the type of fault slip, and obtained a rupture model of the mainshock by performing a finite fault inversion. Our results show that the mainshock was intra-slab, with an estimated depth of 58 km and was followed by, on average, deeper aftershocks that ranged in depth from 57 to 69 km. The source mechanism solution of selected aftershocks reveal that they rupture along a thrust fault oriented almost parallel to the trench, which is consistent with the mainshock source solution. The rupture modelling results indicate that the earthquake is characterised by a high stress-drop and compact rupture area, which together with its depth of nearly 60 km, may explain the relatively small number of aftershocks that were recorded. [Display omitted] • The recent destructive intra-slab earthquake in East Java had few aftershocks. • This may be due to high stress-drop, compact rupture area, and focal depth of 60 km. • Such moderate-sized earthquakes can be a significant source of seismic hazard. [ABSTRACT FROM AUTHOR]

From the mainshocks of 85 Taiwan earthquakes ( M > 5) and their aftershocks reported in the Earthquake Data Report by NEIC PDE catalogue, several correlations between mainshocks and their aftershocks are studied. Results show that the magnitude difference (Δ M) between the mainshock and the largest aftershock slightly increases with the mainshock magnitude ( M) and varies from 0.1 to 2.2, with two values of 0.3 and 0.9 having the largest numbers of events. The mean value of Δ M is 0.83 ± 0.46. The differences of occurrence time and epicenter between the mainshock and the largest aftershock do not clearly correlate to M as well as Δ M. For the whole data set, 36.5 and 77.7% of the largest aftershocks are located near their individual mainshocks within a distance of 10 and 40 km, respectively. The difference in occurrence time somewhat increases as the difference of epicenters increases. [ABSTRACT FROM AUTHOR]

The April 3, 2017 M W 6.5, Moiyabana (Botswana) earthquake occurred in the continental interior of the Nubian plate and in a seismogenic region previously considered as stable. Our objective is to combine several approaches (field and remote sensing investigations) in order to adopt a multidisciplinary strategy so as to enhance our understanding of earthquake occurrence in intraplate southern Africa. We analyse the mainshock and aftershocks sequence based on a local seismic network and local seismotectonic characteristics. The earthquake rupture geometry is constrained with more than 900 aftershocks recorded over a period of three months and from the InSAR analysis of Sentinel-1 images (ascending orbit). The mainshock (25.134 E, 22.565 S; depth 22 ± 3 km) was followed by more than 500 events of magnitude M ≥ 0.8 recorded in April 2017 including the largest aftershock (M W 4.6 on the April 5, 2017). Focal mechanism solutions of the mainshock and aftershocks display predominance of NW-SE trending and NE dipping normal faulting. Stress inversion of the focal mechanisms produced results that are compatible with a NE-SW extension under normal faulting regime. The InSAR study shows fringes (a pair of ascending images 2017-03-30 and 2017-04-11) with two lobes with 3.86 cm–5.15 cm coseismic slip on a NW-SE elongated and 40-km-long surface deformation consistent with the mainshock location and normal faulting mechanism. The modelling of surface deformation provides the earthquake rupture dimension at depth with ~50 cm maximum slip on a fault plane striking 315°, dipping 45°, −80° rake and with M o 3.68 × 1018 Nm. Although the seismic strain rate is of low level, the occurrence of the 2017 Moiyabana earthquake, followed by an aftershock sequence in the central Limpopo Mobile Belt classifies the intraplate region as an active plate interior. • A study of the 2017 Botswana aftershock sequence in a continental interior. • The fault geometry from aftershocks analysis, InSAR and tectonic geomorphology. • Understanding earthquake generation processes using near-field seismology. • Possible development of new rifting zones within Nubia continental domain. [ABSTRACT FROM AUTHOR]