Seismic Gap Research Articles

Space‐Time Stress Variations on the Palu‐Koro Fault Impacting the 2018 Mw 7.5 Palu Earthquake and Its Seismic Hazards

AbstractIn this study, we calculated the Coulomb stress change before and after the 2018 Palu earthquake (Mw 7.5) induced by historical large earthquakes on and around the Palu‐Koro fault (PKF) within Sulawesi Island, Indonesia. We found that the 1996 earthquake (Mw 7.9) on the Minahassa thrust likely promoted the 2018 Palu earthquake by stress loading on its hypocenter. Stress shadows in the PKF impacted the 2018 earthquake rupture’s southward unilateral propagation and termination. Stress increases in the two seismic gaps to the north and south ends of the PKF have resulted in increased seismic hazards, calling close attention to hazard prevention in central Sulawesi. This indicates that fault‐interaction‐induced stress variations on the PKF significantly controlled the 2018 Palu earthquake and its seismic hazards. Our study is important for understanding stress triggering between the subduction earthquakes and intraplate earthquakes in thrust and strike‐slip faults systems globally.

(Mis)informed During COVID-19: How Education Level and Information Sources Contribute to Knowledge Gaps

As COVID-19 swept across the globe, disrupting people’s lives through lockdowns and health concerns, information about how to stay safe and how to identify symptoms spread across media of all forms. Using survey data we collected in April 2020 on a national sample of Americans, we tested the knowledge gap hypothesis by examining how people’s education levels relate to their knowledge about COVID-19 as well as their susceptibility to fake news, and whether information sources moderate this relationship. Our findings suggest that a knowledge gap exists, with those with higher education levels displaying higher levels of knowledge. In contrast, education level did not play a role in believing false information. Moreover, higher news consumption through radio, print newspapers and magazines, and especially social media was associated with lower levels of knowledge and more fake news beliefs. However, news media consumption did not moderate the relationship between education and either knowledge or fake news beliefs, meaning that the media did not explain the education-based knowledge gap during the early months of the COVID-19 pandemic.

Adjoint slip inversion under a constrained optimization framework: revisiting the 2006 Guerrero slow slip event

SUMMARYTo shed light on the prevalently slow, aseismic slip interaction between tectonic plates, we developed a new static slip inversion strategy, the ELADIN (ELastostatic ADjoint INversion) method, that uses the adjoint elastostatic equations to compute the gradient of the cost function. ELADIN is a 2-step inversion algorithm to efficiently handle plausible slip constraints. First it finds the slip that best explains the data without any constraint, and then refines the solution by imposing the constraints through a Gradient Projection Method. To obtain a self-similar, physically consistent slip distribution that accounts for sparsity and uncertainty in the data, ELADIN reduces the model space by using a von Karman regularization function that controls the wavenumber content of the solution, and weights the observations according to their covariance using the data precision matrix. Since crustal deformation is the result of different concomitant interactions at the plate interface, ELADIN simultaneously determines the regions of the interface subject to both stressing (i.e. coupling) and relaxing slip regimes. For estimating the resolution, we introduce a mobile checkerboard analysis that allows to determine lower-bound fault resolution zones for an expected slip-patch size and a given stations array. We systematically test ELADIN with synthetic inversions along the whole Mexican subduction zone and use it to invert the 2006 Guerrero Slow Slip Event (SSE), which is one of the most studied SSEs in Mexico. Since only 12 GPS stations recorded the event, careful regularization is thus required to achieve reliable solutions. We compared our preferred slip solution with two previously published models and found that our solution retains their most reliable features. In addition, although all three SSE models predict an upward slip penetration invading the seismogenic zone of the Guerrero seismic gap, our resolution analysis indicates that this penetration might not be a reliable feature of the 2006 SSE.

Seismic landslide hazard assessment of central seismic gap region of Himalaya for a Mw 8.5 scenario event

In this study, seismic landslide hazard analysis is performed for central seismic gap (CSG) region of Himalaya for a future scenario earthquake of magnitude (Mw) 8.5. Initially, PGA values are estimated by using stochastic finite fault seismological model. Further, the PGA values along with slope displacement prediction equation are used to estimate the Newmark’s sliding displacement. Monte Carlo simulations are performed by considering uncertainties in the material properties. Finally, the hazard map in terms of the probability of slope displacement (DN) value exceeding the threshold values of 5 cm is presented. The probability value varies between 0.1 and 1 and high probability in higher Himalayas highlights the possibility of huge number of co-seismic landslides in this region. The developed seismic landslide hazard map will help local authorities and planners with tools for assessing the seismic landslide risk associated with the use of land and taking necessary measures to minimize the damages.

Confirmation and Characterization of the Rupture Model of the 2017 Ms 7.0 Jiuzhaigou, China, Earthquake

AbstractOn 8 August 2017, an Ms 7.0 earthquake struck the Jiuzhaigou town, Sichuan Province, China, rupturing an unmapped fault, which is adjacent to the Maqu seismic gap in the Min Shan uplift zone in the easternmost part of the Bayan Har block. Having summarized the previous studies on the source of this earthquake, we confirmed the rupture model by jointly inverting the teleseismic P-wave and SH-wave data, Interferometric Synthetic Aperture Radar line-of-sight displacement data, and the near-field seismic and strong-motion data, a most complete dataset until now. The confirmation showed that a scalar seismic moment of 6.6×1018 N·m was released (corresponding to a moment magnitude of Mw 6.5), and 95% of the release occurred in the first 10 s. The slip area was composed of two asperities, with a horizontal extension of ∼20 km and a depth range of ∼2–15 km. A bilateral extending occurred at shallow depths, but the rupturing upward from deep depth dominated in the early time. The rupture process was found generally featuring the slip-pulse mode, which was related to the weak prestress condition. The aftershocks almost took place in gaps of the mainshock slip because of the coulomb stress change. Combining the aftershock relocations, aftershock focal mechanism solutions, and our confirmed rupture model, we suggest that the seismogenic fault was a northward extension of the mapped Huya fault. The occurrence of this earthquake made the Maqu seismic gap at a higher level of seismic risk, in addition to the moderate to high strain accumulation on the easternmost tip of the Kunlun fault system and the weak lower crust below.

Methodological Reconstruction of Historical Seismic Events From Anecdotal Accounts of Destructive Tsunamis: A Case Study for the Great 1852 Banda Arc Mega‐Thrust Earthquake and Tsunami

AbstractWe demonstrate the efficacy of a Bayesian statistical inversion framework for reconstructing the likely characteristics of large pre‐instrumentation earthquakes from historical records of tsunami observations. Our framework is designed and implemented for the estimation of the location and magnitude of seismic events from anecdotal accounts of tsunamis including shoreline wave arrival times, heights, and inundation lengths over a variety of spatially separated observation locations. The primary advantage of this approach is that all of the assumptions made in the inversion process are incorporated explicitly into the mathematical framework. As an initial test case we use our framework to reconstruct the great 1852 earthquake and tsunami of eastern Indonesia. Relying on the assumption that these observations were produced by a subducting thrust event, the posterior distribution indicates that the observables were the result of a massive mega‐thrust event with magnitude near 8.8 Mw and a likely rupture zone in the north‐eastern Banda arc. The distribution of predicted epicentral locations overlaps with the largest major seismic gap in the region as indicated by instrumentally recorded seismic events. These results provide a geologic and seismic context for hazard risk assessment in coastal communities experiencing growing population and urbanization in Indonesia. In addition, the methodology demonstrated here highlights the potential for applying a Bayesian approach to enhance understanding of the seismic history of other subduction zones around the world.

Triggering an unexpected earthquake in an uncoupled subduction zone.

In the 1970s, the Shumagin Islands region of the Alaska subduction zone was identified as a seismic gap expected to host a future great [moment magnitude (M w) ≥8.0] earthquake. More recent geodetic data indicate that this region is weakly coupled, and the geologic record shows little evidence of past large events. From July to October 2020, a series of earthquakes occurred in this region, raising the possibility of greater coupling. The initial M w 7.8 thrust faulting earthquake straddled the eastern edge of the Shumagin Gap and was followed by an M w 7.6 strike-slip earthquake within the Shumagin Gap. Stress modeling indicates that this strike-slip earthquake is in fact favored if the Shumagin Gap has low coupling, whereas a highly coupled Shumagin Gap inhibits that type and location of earthquake. The initial thrust earthquake and its afterslip enhanced the strike-slip loading within the subducting slab, helping to trigger the October event.

The 22 July 2020 MW 7.8 Shumagin seismic gap earthquake: Partial rupture of a weakly coupled megathrust

The earthquake potential of the Shumagin seismic gap along the Alaska Peninsula (∼162°W to ∼158.5°W) has been debated for more than 40 years. On 22 July 2020, the eastern half of the gap hosted an MW 7.8 earthquake involving a patchy rupture of the megathrust in the depth range of 20 to 45 km. The space-time slip distribution is determined by joint inversion of teleseismic P and SH waves and static displacements from regional GPS stations. The event initiated near the epicenter of the 10 November 1938 (MW 8.2) event, and ruptured westward, with little/no overlap with the 1938 rupture zone. The main slip patch has peak slip of ∼3.8 m below the Shumagin Islands, and produced ∼30 cm uplift and ∼25 cm SSE horizontal displacement on Chernabura Island. The slip model predicts well the small (<1 cm) tsunami signals persisting for more than ten hours observed at deep-water DART seafloor pressure recordings along the Alaska-Aleutian arc. Aftershocks with depths from 20 to 40 km fringe the large-slip patches, and show westward concentration during the first month after the mainshock. Aftershocks up-dip of the 1948 MW 7.1 event contribute to the high level of modest-size background seismicity extending to the trench in the region of very low seismic coupling (0.0–0.1) in the western Shumagin gap east of the 1 April 1946 (MW 8.6) rupture zone. The 31 May 1917 event is the last major earthquake to rupture the eastern half of the Shumagin gap, and has a lower surface wave magnitude (MSG-R 7.4, horizontal components) compared to the 2020 event (MSG-R 7.7, vertical components). Comparison of instrument-equalized waveforms for the 1917 and 2020 events indicates similar size contrast and differences in overall rupture duration and slip complexity. The 2020 rupture has average slip of ∼1.9 m over the 3600 km2 region with co-seismic slip ≥1 m. This is much less than the ∼6.7 m of potentially accumulated slip deficit since 1917, consistent with geodetic estimates of low average seismic coupling coefficient of 0.1–0.4. The megathrust seaward of the 2020 event has low seismicity and may either be aseismic or capable of comparable size ruptures. Comparisons are made with other subduction zones that have experienced relatively deep megathrust slip in regions with moderate seismic coupling.

Mind The Gap! The Role of Political Identity and Attitudes in the Emergence of Belief Gaps

Abstract To more fully understand the belief gap hypothesis, this study examines the effect of political identity, education, and partisan media consumption on the formation of attitudes and false beliefs. Using a two-wave, nationally representative online survey of the U.S., we assess people’s attitudes and beliefs toward climate change, on the one hand, and Syrian refugees, on the other. Building on previous studies, we demonstrate that the effect of one’s political identity on attitudes and false beliefs is contingent upon education, which appears to widen the belief gap in consort with political identity.

Prediction of different depth amplifications of deep soil sites for potential scenario earthquakes

Deep soil basin is one of the geographical features which significantly alter the response to earthquakes. Around the world, there are regions where bedrock is at a substantial depth upon which are different layers of soil. Larger depths of soil alter the response toward earthquakes and have been reported in the past. Indo-Gangetic Basin (IGB) of India is one of the seismically vulnerable deep soil basins of the Asian continent. The present paper attempts to study the site amplifications in IGB at the surface and different depths to understand the amplification behavior of the deep soil basins worldwide. Sixteen different probable scenario earthquakes are identified based on past seismic gaps, history and seismic studies and simulated at 270 sites covering whole deep soil region of the IGB. Representative depths of input motion, density, shear wave velocity, location of the water table, suitable shear modulus reduction and damping curves have been used. One-dimensional nonlinear site response analysis was carried out using DEEPSOIL. Peak ground acceleration (PGA), peak spectral acceleration (PSA), amplification factors using the ratio of zero period, peak spectral acceleration, site factors Fa and Fv as per the National Earthquake Hazards Reduction Programme (NEHRP) and spectral accelerations at specific periods of 0.2 and 1 s are calculated and deliberated at the surface and also at different layers up to 100 m depth. Maps for spatial variation in average and maximum values of amplification as well as site factors have been presented. Average values of FPGA, FPSA, Fa and Fv at the surface were found in the range of 1.16–7.94, 1.13–7.93, 1.43–7.89 and 2.11–7.51, respectively. Around 14% of sites in the IGB have amplification values at subsurface levels exceeding those at corresponding surface levels. Amplifications observed at the subsurface level are less than that of the surface for a considerable number of sites.

UNDER INVOICING IN THE RESIDENTIAL REAL ESTATE MARKET IN PAKISTAN

In this paper the meaning of “under invoicing in a real estate market” signifies that the market value of real property exceeds its record value appearing in government documentation. The purpose of this study is to identify the level of under invoicing and determine the factors that affect the under invoicing in real estate markets in Pakistan. We apply OLS and Extreme Bounds Analysis techniques to test our propositions. The statistical sample consists of 338 real estate contracts. We find that under invoicing is determined by a multiplicity of factor. These include: the capital gains tax rate, the measurable amount of corruption in the economy, the risk-free rate, a buyer’s profession, the reputation of the local housing authority, and the degree of disequilibria in regional real estate markets. Our findings are consistent with four distinct hypotheses: (a) tax evasion hypothesis, (b) widening gap hypothesis, (c) a corruption hypothesis and (d) a signaling hypothesis. The evidence suggests that higher rates of taxation and a larger statistical incidence of corruption in markets tend to be associated with a greater probability of under-invoicing. The findings of the study have practical implications for those investors who are interested in real estate markets of emerging and developing economies.

The slip deficit on the North Anatolian Fault (Turkey) in the Marmara Sea: insights from paleoseismicity, seismicity and geodetic data

The North Anatolian Fault experienced large earthquakes with 250–400 years recurrence time. In the Marmara Sea region, the 1999 (Mw = 7.4) and the 1912 (Mw = 7.4) earthquake ruptures bound the Central Marmara Sea fault segment. Using historical-instrumental seismicity catalogue and paleoseismic results (≃ 2000-year database), the mapped fault segments, fault kinematic and GPS data, we compute the paleoseismic-seismic moment rate and geodetic moment rate. A clear discrepancy appears between the moment rates and implies a significant delay in the seismic slip along the fault in the Marmara Sea. The rich database allows us to identify and model the size of the seismic gap and related fault segment and estimate the moment rate deficit. Our modelling suggest that the locked Central Marmara Sea fault segment (even including a creeping section) bears a moment rate deficit $${\dot{M}}_{d}$$ = 6.4 × 1017 N.m./year that corresponds to Mw ≃ 7.4 for a future earthquake with an average ≃ 3.25 m coseismic slip. Taking into account the uncertainty in the strain accumulation along the 130-km-long Central fault segment, our estimate of the seismic slip deficit being ≃ 10 mm/year implies that the size of the future earthquake ranges between Mw = 7.4 and 7.5.

Kinematics of the Marmara Region: a fusion of continuum and block models

The Sea of Marmara has been the focus of numerous marine geophysical studies during the last couple of decades. Determination of the interseismic slip distribution along the Main Marmara Fault (MMF) has observational difficulties due to the fact that the fault is under the sea. In addition to the onshore geodetic studies, two underwater geodetic studies were carried out recently and brought new clues about locked/creeping status of two different fault segments. In this study, we investigate the interseismic deformation of the Marmara region from a kinematic perspective using both block and continuum kinematic models. Block model inversion yields relative motion along the block boundaries as well as the distribution of slip deficit on the faults bounding the blocks. Calculated long term slip rates are 19–20 mm/yr for the MMF and 3–4 mm/yr for the Southern branch of the North Anatolian Fault (SNAF). In order to determine the sensitivity of the slip deficit solution to arbitrary spatial discretizations, we perform a series of checkerboard tests and optimize node distribution on the MMF accordingly. We also explore the sensitivity of inversion results on the MMF to assumptions regarding SNAF long term slip and interseismic locking. This study shows that the underwater geodetic data can be combined with the GPS data in a joint inversion, bringing a better constrained slip deficit distribution on the MMF. MMF has aseismic creep in the west of the Marmara Sea, with creep rates approaching long term slip rates in the Central Basin. On the other hand, the fault appears locked from \(\sim\)28.2°E eastward. In the best fitting model, the fault segment across Silivri is locked down to \(\sim\)10 km. The existence of a hazardous seismic gap in the Sea of Marmara, potentially yielding a magnitude 7.5 earthquake, is thus confirmed. The continuum approach is used to calculate strain rate fields from GPS data alone, from the output (slip rates and block average strain rates) of the best-fitting block model, and from the GPS residuals of this model. Our continuum models show that most of the accumulated strain in the Marmara region is indeed focused around the MMF, but also that strain distributed within the blocks cannot be neglected. On the other hand, the SNAF system differs from the MMF in that it appears as a 50 km wide zone of deformation with a patchy distribution of strain reflecting the activity of individual faults.

Seismotectonics and stress perspective of the Kumaon Himalaya: A geophysical evidence of a Lesser Himalayan duplex

The Kumaon Himalaya lies in the central seismic gap and therefore bears the potential to host a great Himalayan earthquake. The seismicity and seismotectonics of the Kumaon Himalaya and the adjacent region have been investigated based on local earthquake data recorded at 18 seismological stations. The seismically active zone of the eastern segment of the Kumaon Himalaya deviates from the usual pattern of seismicity in the Himalayan Seismic Belt of the NW Himalaya. Shallow-focus earthquakes in this region largely concentrate in the Chiplakot Crystalline Belt (CCB) immediately south of the Vaikrita Thrust. The Focal Mechanism Solutions of 41 earthquakes computed through waveform inversion technique along with the solutions of 12 earthquakes obtained from the Global Centroid Moment Tensor solution catalog are used to investigate the kinematics of the region. The study reveals a complex faulting pattern in the Inner Lesser Himalaya. The stress inversion results show a widely distributed stress pattern and low frictional coefficient which are attributed as one of the major causes of clustered seismicity observed in the CCB. Careful examination of the fault orientations indicate the presence of a hinterland dipping Lesser Himalayan Duplex over the ramp structure on the Main Himalayan Thrust. The high compressive stress and deformation rate in the CCB are partially accommodated by this duplex structure. The large concentration of shallow-focus earthquakes in the CCB is the result of the presence of fluid-rich zone as well as strain localization and large stress build-up due to locking in the ramp structure on the Main Himalayan Thrust beneath the CCB.

Seismic hazard of multi-segment rupturing for the Anninghe–Zemuhe–Daliangshan fault region, southeastern Tibetan Plateau: constraints from geological and geodetic slip rates

The Anninghe–Zemuhe–Daliangshan region is deformed by two parallel faults, i.e., the Anninghe–Zemuhe fault and the Daliangshan fault. A large seismic gap that characterizes the AZD region in the past 30 years has attracted significant research attentions to study the seismic hazard of these faults. However, it still remains a matter of debate whether the southern part of the Anninghe fault was ruptured with the Zemuhe fault in the 1850 M7.5 earthquake. The multi-segment rupture probabilities should be considered in the seismic hazard analysis. In this study, we divide the Anninghe fault, the Zemuhe fault and the Daliangshan fault into segments which are then used to build different multi-segment rupture combination models. First, we invert the fault slip rate in an elastic block model. Using both the geological and inverted geodetic slip rates as input constraints, we model the seismicity rates on the fault segments. Then, we compare the modeled seismicity rates with the historical earthquake catalog to test the validity of the models. The model, which does not consist of the multi-segment span the Anninghe fault and the Zemuhe fault, and the multi-segment combinations among the segments of the south Daliangshan fault and the north Xiaojiang fault, has the seismicity rates generally consistent with the fault slip rates and historical records. Finally, we use the compatible fault model to calculate the 475-year PGA values. Our modeled PGA values, from both the geological and geodetic slip rates, are averagely higher than those from the National Zonation Map. This methodology is more reasonable as it considers the fault slip rate and multi-segment rupture.

Seismotectonic implications of the South Chile ridge subduction beneath the Patagonian Andes

AbstractThe South Chile ridge (SCR) intersects the Patagonian trench around 46°09′S, forming the triple junction among the Antarctic, Nazca, and South America plates. Subduction of the SCR since ~18 Ma produced the opening of a slab window beneath Patagonia and a noticeable magmatic gap in the cordillera, profuse volcanism and topographic uplift in the retroarc. To study seismicity distribution and present‐day stress resulting from this particular framework, we analyse databases of seismic events and earthquake focal mechanisms. Our study finds that clusters of intraplate crustal seismic events are disrupted by a ~450–470 km seismicity gap above the slab window. Calculated stress tensors depict a strike‐slip tectonic regime north of the triple junction, and ~W‐E compression to the south of the seismic gap. We propose that the seismotectonic behaviour of the upper plate is disturbed at the first order by the trench‐ridge intersection, leading to a heterogeneous stress field.

Interseismic slip rate and locking along the Maqin–Maqu Segment of the East Kunlun Fault, Northern Tibetan Plateau, based on Sentinel-1 images

Abstract The East Kunlun Fault (EKF) is one of the most active left-lateral strike-slip faults of the Tibetan Plateau and defines the northern boundary of the Bayan Har Block. Many strong earthquakes have occurred over the past century in the western segment of the EKF, whereas few historical earthquakes have occurred in the eastern segment, that is, the Maqin–Maqu segment (MMS). Therefore, the MMS is widely recognized as a seismic gap with high risk. For this purpose, the Interferometric Synthetic Aperture Radar (InSAR) technique was used to process Sentinel-1 images of the MMS in the EKF to determine the interseismic deformation velocity field during 2014–2019. Then, the slip rate and locking of the MMS were obtained. The results are as follows. (1) The slip rate gradually decreased from west to east along the Maqin–Maqu Segment, i.e., from ~8 mm/year to ~2 mm/year, and a significantly low slip-rate zone exists near the Maqin Segment. (2) Four asperities having a high seismic risk were identified in the Maqin–Maqu Segment. (3) Based on the determined slip rate and previous studies, we propose that the deformation of the Bayan Har Block can be explained with a nonrigid passive bookshelf model.

Potential seismogenic asperities in the Garhwal–Kumaun region, NW Himalaya: seismotectonic implications

The Garhwal–Kumaun region (29°–31.5°N; 77°–81°E) in NW Himalaya lies in the Central Seismic Gap where the accumulated strain energy is sufficient for a future great earthquake. A broadband seismic network is continuously monitoring the seismic activity in this region and recorded a total of 3634 well located seismic events justified within the acceptable error bars (ERZ, ERH < 5.0) from 2007 to 2018 with hypocentral distances ranging from 0 to 350 km. In the present work, frequency-magnitude distribution (b-value) and fractal dimension (Dc-value) are investigated along (NW–SE) and across (SW–NE) the strike of Garhwal–Kumaun Himalaya. The study area has been divided into three different seismogenic asperities. Our results revealed that the proximity of Rudraprayag–Chamoli region exhibits significant low b-value (0.702 ± 0.03) and Dc-value (1.38 ± 0.03) and indicates high stress accumulation. The region has witnessed 1999 Chamoli earthquake Mb 6.3 and 2017 Rudraprayag earthquake M 5.7. A detailed study of b-value and Dc-value variation as a function of depth is also examined. The composite trend in abrupt escalation of b-value is observed at depth ≈ 12 km for Garhwal region and ≈ 7 km for Kumaun region. A well demarcation of crustal heterogeneity, high stress regime and associated seismogenic asperity is plotted. The low b-value and Dc-value depth ranges are coinciding with mid-crustal ramp and exhibiting a potential zone (12–15 km) for future great earthquake in the Garhwal region.

Locking-derived tsunami scenarios for the most recent megathrust earthquakes in Chile: implications for tsunami hazard assessment

The ever-increasing data from continues geodetic networks has allowed to reveal first-order spatial relations between pre-seismic highly locked zones on the interface and regions of large coseismic slip. Here we use a distribution of locking degree and recurrence of historical earthquakes along the Chilean subduction zone to estimate the slip deficit accumulated since previous tsunamigenic earthquakes and use these constrains to simulate tsumani signals. We generate tsunami models for the recent five major tsunamigenic earthquakes in Chile during the last decade: Maule (2010), Pisagua (2014), Illapel (2015), Melinka (2016) and Valparaiso (2017). Results were compared with tsunami records to evaluate the use of locking degree as an estimate of displacement of future earthquakes and as a tool for tsunami hazard assessment. Our tsunami simulations for the Maule (2010) and Illapel (2015), earthquakes that filled a seismic gap, reproduce well the tsunami observations, for the case of Pisagua (2014), Valparaiso (2016) and Melinka (2017) although it exists a correspondence in the areas of greater degree of locking with the coseismic slip, there is also an imbalance between the energy accumulated and released in the interseismic period considered according to the historical seismicity. This indicate that the rupture of small asperities (areas that release high slip during earthquakes) may have a complex pattern of recurrence and do not fully affect a locked patch. Locking-derived tsunami scenarios represent well tsunami observations of earthquakes that ruptured a locked seismic gap, and they can be used in addition to the actual methodologies to improve the estimation of tsunami hazard.

Earthquake potential of the seismic gap between the Wenchuan and Lushan earthquakes: Current status, thoughts, and challenges

Earthquake potential of the seismic gap between the Wenchuan and Lushan earthquakes: Current status, thoughts, and challenges