Earth and Planetary Science Letters最新文献

{"title":"Multilevel Mechanisms Driving Intraplate Volcanism in Central Mongolia Revealed by Adjoint Waveform Tomography of Receiver Function and Ambient Noise Data","authors":"Mijian Xu ,&nbsp;Kai Wang ,&nbsp;Jing Chen ,&nbsp;Jing He ,&nbsp;Qinya Liu ,&nbsp;Yiduo Liu ,&nbsp;Zhouchuan Huang ,&nbsp;Ping Tong","doi":"10.1016/j.epsl.2024.119137","DOIUrl":"10.1016/j.epsl.2024.119137","url":null,"abstract":"<div><div>The genesis of the Cenozoic intraplate volcanism in Central Mongolia, characterized by sustained and low-volume eruptions remains debated due to the lack of a comprehensive model to interpret the Cenozoic volcanic activities. Here, we introduce a high-resolution 3D velocity model of the Hangay Dome, using a novel joint method which combines receiver function adjoint tomography and ambient noise adjoint tomography. The small-scale low-velocity zones in the crust and uppermost mantle reveal a crustal magma reservoir and partially molten subcontinental lithospheric mantle (SCLM). Melt fraction estimation indicates low-degree partially molten crust and SCLM. Combining previous geophysical and geochemical observations, we suggest that the volcanism in the Hangay Dome is driven by multilevel mechanisms. The remnant Mesozoic volatiles triggered upper mantle upwelling. This upwelling accumulated in the asthenosphere, heating the SCLM, and prompted its low-degree partial melting. The molten SCLM caused local lithospheric thinning and facilitated the magmatic underplating in the lower crust, eventually leading to the formation of the crustal magma reservoir.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"650 ","pages":"Article 119137"},"PeriodicalIF":4.8,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Melting the Marinoan Snowball Earth: The impact of deglaciation duration on the sea-level history of continental margins","authors":"Freya K. Morris ,&nbsp;Tamara Pico ,&nbsp;Jessica R. Creveling ,&nbsp;John Grotzinger","doi":"10.1016/j.epsl.2024.119132","DOIUrl":"10.1016/j.epsl.2024.119132","url":null,"abstract":"<div><div>The termination of the Marinoan Snowball Earth (∼635 Ma) represents a significant transition in Earth's climate. Cap carbonate strata, and underlying glaciogenic deposits, record global deglaciation and preserve diverse relative sea-level histories, representing the intersection of global mean sea-level rise with regional forcings such as glacial isostatic adjustment and sedimentation. For example, at cap carbonate outcrops in the Naukluft Mountains of central Namibia, facies transitions reveal two intervals of water-depth deepening and shallowing. While many factors may have contributed to this deglacial pattern of relative sea-level change, here we consider the possibility that this, and other, non-monotonic sea-level histories, were driven by glacial isostatic adjustment. We modeled relative sea-level change due to glacial isostatic adjustment for a globally synchronous and continuous Marinoan deglaciation, and explored how the duration of deglaciation impacts the range of resulting relative sea-level patterns across continental margins. Short Snowball deglaciation durations, on the order of ∼2 kyr, result in exclusive relative sea-level rise, or relative sea-level rise followed by relative sea-level fall but cannot drive two distinct phases of relative sea-level fall. However, longer duration Snowball deglaciations, of ∼10–30 kyr, can drive two distinct intervals of relative sea-level rise and fall across much of the width of a continental margin, which may have contributed to the stratal patterns observed in Naukluft Mountains cap carbonate, though we cannot exclude that the pattern arises from changes in sediment supply or other factors. This work underlines the need for better constraints on the areal distribution and volume of Marinoan ice sheets from field observations, as well as plausible deglacial durations from global climate models.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"650 ","pages":"Article 119132"},"PeriodicalIF":4.8,"publicationDate":"2024-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142705426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First cycle or polycyclic? Combining apatite and zircon detrital U-Pb geochronology and geochemistry to assess sediment recycling and effects of weathering","authors":"Emily S. Finzel ,&nbsp;Stuart N. Thomson ,&nbsp;David M. Pearson ,&nbsp;L．Kenneth Horkley ,&nbsp;Kacey Garber ,&nbsp;Cole Gardner","doi":"10.1016/j.epsl.2024.119131","DOIUrl":"10.1016/j.epsl.2024.119131","url":null,"abstract":"<div><div>Even with the advent of multiple new geochronologic provenance techniques in recent decades, almost all provenance studies are still hampered by a fundamental limitation: recycling of older strata is often a significant concern but cannot be adequately addressed using current techniques. Detrital zircon is the dominant mineral used in provenance studies, but zircons are robust and almost always represent both first-cycle and polycyclic sediment contributions in a sandstone. To overcome these issues, we implement two relatively novel applications of detrital geochronology – U-Pb geochronology and trace and rare earth element geochemistry of detrital apatite – to take a multi-method approach of analyzing both mineral phases from the same sandstone. Our results indicate that zircon and apatite detrital age distributions from the same sandstone that are nearly identical, paired with apatite TREE geochemistry denoting an igneous source, are a key diagnostic indicator of sediment derived from shallowly-emplaced (&lt;∼500 °C) or extrusive igneous rocks. Detrital age distributions that are similar but offset from one another such that the apatite peaks are younger than the zircon peaks and also young up-section, paired with apatite TREE geochemistry denoting an igneous source, implies exhumation of a deep igneous source through the apatite U-Pb closure temperature. The combination of detrital zircon and apatite U-Pb geochronology and TREE geochemistry also permits detection of recycled versus first-cycle components from metamorphic basement terranes. This study signifies a significant advance in provenance research by demonstrating the facility of combining detrital apatite and zircon U-Pb geochronology and geochemistry to decipher first-cycle versus polycyclic sediment from various types of igneous and metamorphic rocks. Our results show this methodology has potential applications and implications for all types of sedimentary systems, paleogeographic reconstructions, provenance interpretations, and tectonic reconstructions.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"650 ","pages":"Article 119131"},"PeriodicalIF":4.8,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142705425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ocean crustal veins record dynamic interplay between plate-cooling-induced cracking and ocean chemistry","authors":"Aled D. Evans ,&nbsp;Rosalind M. Coggon ,&nbsp;Michelle Harris ,&nbsp;Elliot J. Carter ,&nbsp;Elmar Albers ,&nbsp;Gilles M. Guérin ,&nbsp;Thomas M. Belgrano ,&nbsp;Mallika Jonnalagadda ,&nbsp;Lewis J.C. Grant ,&nbsp;Pamela D. Kempton ,&nbsp;David J. Sanderson ,&nbsp;James A. Milton ,&nbsp;Timothy J. Henstock ,&nbsp;Jeff C. Alt ,&nbsp;Damon A.H. Teagle","doi":"10.1016/j.epsl.2024.119116","DOIUrl":"10.1016/j.epsl.2024.119116","url":null,"abstract":"<div><div>As ocean crust traverses away from spreading ridges, low-temperature hydrothermal minerals fill cracks to form veins, transforming the physical and chemical properties of ocean crust whilst also modifying the composition of seawater. Vein width and frequency observations compiled from the International Ocean Discovery Program (IODP) South Atlantic Transect (∼31°S) and previous scientific ocean drilling holes show that vein width distributions progressively broaden and observed strain <span><math><mrow><mo>(</mo><mrow><mstyle><mi>Σ</mi></mstyle><msub><mi>m</mi><mtext>veins</mtext></msub><mo>/</mo><msub><mi>m</mi><mtext>core</mtext></msub></mrow><mo>)</mo></mrow></math></span> increases with crustal age, whereas vein densities <span><math><mrow><mo>(</mo><mrow><msub><mo>#</mo><mtext>veins</mtext></msub><mo>/</mo><msub><mi>m</mi><mtext>core</mtext></msub></mrow><mo>)</mo></mrow></math></span> remain approximately constant. Elemental mapping and textural observations illuminate multiple precipitation and fracturing episodes that continue as the ocean crust ages. This challenges the existing notion that ocean crustal veins are passively filled; rather, they are dynamic features of ocean crust aging. These data, combined with thermal strain modelling, indicate a positive feedback mechanism where cooling of the ocean plate induces cracking and the reactivation of pre-existing veins, ultimately resulting in further cooling. Waning of this feedback provides a mechanism for the termination of the global average heat flow anomaly. Sites with total vein dilation greater than expected for their age correspond with crustal formation during periods of high atmospheric CO₂. The amount of vein material thus reflects the changing balance between ocean plate cooling, ocean chemistry, and the age of the ocean crust. Our results demonstrate that ocean crust endures as an active geochemical reservoir for tens of millions of years after formation.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"650 ","pages":"Article 119116"},"PeriodicalIF":4.8,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142705424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Context matters: Modeling thermochronologic data in geologic frameworks using the Great Unconformity as a case study","authors":"R.M. Flowers,&nbsp;B.A. Peak","doi":"10.1016/j.epsl.2024.119061","DOIUrl":"10.1016/j.epsl.2024.119061","url":null,"abstract":"<div><div>The critical importance of sample context and geologic information for interpreting geochronologic data has long been fundamental to the Earth sciences. However, the lack of quantitative uncertainties associated with contextual, observational information means that much geologic data cannot be statistically treated in computational models using the same approaches as quantitative datasets. This challenge is showcased by the current debate over whether and how geologic data should be used when modeling thermochronologic results, which has important implications for deriving time-temperature (tT) paths from which burial and exhumation histories are interpreted. Holistically leveraging observational data to test hypotheses and determine the set of geologically reasonable thermal histories that can explain thermochronologic results has a longstanding history, but some recent studies have criticized this approach as one that arbitrarily limits tT solutions. Here, a geologic context approach to thermal history modeling, in which observational and thermochronologic datasets are combined to design geologically valid models and reach the most geologically likely interpretation, is illustrated using an example of constraining Great Unconformity exhumation in Colorado where this modeling philosophy has been questioned. Although the quality of geologic data and their applicability to modeled samples can vary and be debated, this does not mean that all geologic data are inherently unreliable and therefore discardable. Exploring models with varying or minimal constraints can be useful to test different hypotheses and determine the resolving power of the data, but using an endmember context-blind approach to interpret thermochronologic results can produce outcomes that violate fundamental aspects of the geology. The strategy outlined here is not the only valid approach to modeling thermochronologic data, but if the purpose of the modeling is to derive meaningful interpretations about sample tT paths in order to better illuminate the geologic history, then critical thinking about the sample context, first order geologic observations, and primary relationships should be integral components of the modeling process.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"650 ","pages":"Article 119061"},"PeriodicalIF":4.8,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142705494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seismic radial anisotropy in southeastern Tibetan Plateau and its implications for regional geodynamic evolution","authors":"Shaoqian Hu ,&nbsp;Huajian Yao ,&nbsp;Jikun Feng ,&nbsp;Hui Huang ,&nbsp;Qiyuan Liu ,&nbsp;Robert D. van der Hilst","doi":"10.1016/j.epsl.2024.119122","DOIUrl":"10.1016/j.epsl.2024.119122","url":null,"abstract":"<div><div>The southeastern Tibetan Plateau exhibits intricate crustal tectonics, encompassing recent seismic megathrust events. Previous research suggested the presence of north-south-oriented channelized viscous flow within the crust. However, recent investigations have unveiled a notable northeast-southwest-oriented geological structure, potentially rigid, intersecting with the presumed crustal channelized flow. Several questions persist regarding the composition of the northeast-southwest-oriented structure, the continuity of crustal channelized flow, and the interplay between them. In this study, dispersion data from a dense seismic array are employed to significantly refine regional crustal models for shear wave velocity and radial anisotropy through ambient noise tomography. The resulting high-resolution model further reveals the style of the crustal deformation and supports the interpretation that the northeast-southwest structure, which shows higher velocity and significant negative radial anisotropy, results from mafic material at the base of crust, obstructing the crustal channelized flow. However, the northeast-southwest structure is not as rigid as the Sichuan Block and exhibits depth-dependent deformation. The interpretation proves useful in further understanding regional earthquake focal mechanisms and strain distribution. Additionally, this research identified a region of generalized negative radial anisotropy in the crust of the western Chuan-Dian fragment, suggesting a reduced horizontal channel crustal flow in this area. Drawing upon various geophysical and geological evidence, we present a geodynamic evolution model, proposing a sequence of events: Permian plume activity resulting in mafic material at the base of the crust near Anninghe-Zemuhe fault, northward advancement of the east Himalayan syntaxis inducing crustal compressional stress field, reduced lower crustal channel flow in the western Chuan-Dian fragment leading to the regional east-west extension, and initiation of the Xianshuihe fault causing shift of strain concentration and depth-dependent deformation near the Anninghe-Zemuhe fault. The geodynamic model provides valuable insights into the regional distribution of crustal strain and the underlying mechanisms of large seismic events.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"649 ","pages":"Article 119122"},"PeriodicalIF":4.8,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142706388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluid-mediated transition from dynamic rupturing to aseismic slip at the base of the seismogenic continental crust","authors":"Alberto Ceccato ,&nbsp;Giorgio Pennacchioni","doi":"10.1016/j.epsl.2024.119117","DOIUrl":"10.1016/j.epsl.2024.119117","url":null,"abstract":"<div><div>Chemo-mechanical fluid-rock interactions are critical in controlling the frictional-viscous transition in the continental crust and the competition between seismic and aseismic deformation in fault zones. In this study, we provide quantitative constraints on the timing and magnitude of weakening, and associated changes in slip rates, due to fluid-rock interactions at the base of the seismogenic continental crust. Integrating field, microstructural analyses, and micromechanical modelling we constrain the microstructural and mechanical evolution of phyllosilicate-rich, carbonate-bearing brittle-ductile faults/shear zones developed in the Rieserferner granitoid pluton (Eastern Alps). Here, transient overpressure of (H₂O + CO₂)-rich fluids triggered dynamic rupturing in the strong host rock (&gt;100 MPa), and promoted the development of weak phyllonites through long-term fluid-mediated feldspar-to-mica reactions. These phyllosilicate-rich fault rocks accommodated frictional-viscous aseismic creep at very low differential stresses (&lt;10 MPa) and near-lithostatic fluid pressure conditions. Microscale vein networks overprinting the phyllonite indicate cyclical embrittlement related to increased creep rates (up to 10⁻⁷ s⁻¹) that occurred over a timeframe of days to months and potentially related to slow earthquakes (slip rates of 10⁻⁸ m/s). These findings offer new constraints on the development and seismogenic potential of phyllosilicate-rich fault zones and on the effect of fluid chemistry on fault zone rheology. Fluid-mediated fault weakening can occur in rather short time (months-to-years) comparable to the interseismic period, progressively promoting long-term, viscous aseismic creep on a previously strong fault zone developed by dynamic rupturing. The combined effect of strain localization, the low permeability of the phyllonitic cores, as well as of fluid chemistry evolution and CO₂-enrichment, may lead to the development of brittle-frictional instabilities during transient accelerated-creep events. Therefore, the fluid-mediated microstructural evolution of phyllosilicate-rich fault rocks controls their seismogenic behaviour, potentially leading to accelerated creep, slow earthquakes and slow slip on otherwise aseismically creeping faults.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"650 ","pages":"Article 119117"},"PeriodicalIF":4.8,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142705495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methane sealed due to the formation of gas hydrate system in the South China Sea","authors":"Limin Gou ,&nbsp;Zijian Zhang ,&nbsp;Xianjun Zeng ,&nbsp;Yulin He ,&nbsp;Canping Li ,&nbsp;Xuewei Liu","doi":"10.1016/j.epsl.2024.119114","DOIUrl":"10.1016/j.epsl.2024.119114","url":null,"abstract":"<div><div>Although the release of methane into oceans and potentially the atmosphere could accelerate climate change, detailed investigations on the gas source from deep-buried strata and its migration through the gas hydrate stability zone (GHSZ) to the seafloor are limited. These studies are often hindered by the presence of diffracted waves and inaccuracies in seismic velocity models, leading to poor seismic imaging that hampers the understanding of gas sources, migration pathways, and gas hydrate accumulation. In the study, we utilize the technique of common scatter point (CSP) gathers to build an accurate velocity model and obtain high-quality images for a complex gas-hydrate and natural-gas petroleum system. The CSP processing enables the accurate migration of reflected and diffracted waves, resulting in improvements in signal-to-noise ratio and lateral resolution. The improved seismic images offer clearer visualization of various petroleum elements. Specifically, we can identify the top of the hydrate zone and base of the free gas zone within a shallow-buried hydrate system, fault geometries within the free gas zone, a middle-buried natural gas reservoir, gas chimneys as migration pathways, and the deep-buried source rock strata beneath the intrusive volcanic rocks. As a result, we reveal a joint prospect of natural-gas reservoir and gas-hydrate system in the deep-water region of the South China Sea. Our results suggest that methane in the natural gas reservoir has migrated upwardly into the hydrate system, and it is unlikely to leak into the water column.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"649 ","pages":"Article 119114"},"PeriodicalIF":4.8,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142706456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chondrites as thermal and mechanical archives of accretion processes in the Solar protoplanetary disk","authors":"Anthony Seret ,&nbsp;Guy Libourel","doi":"10.1016/j.epsl.2024.119066","DOIUrl":"10.1016/j.epsl.2024.119066","url":null,"abstract":"<div><div>As some of the most ancient materials in our Solar System, chondritic meteorites offer a valuable window into the early stages of planetary formation, particularly the accretion processes that built the most primitive asteroids. Until now, high energy shocks and collisions have been invoked to explain the deformation and fragmentation of chondrules, the main component of chondrites. However, simulating the cooling of chondrules using continuum mechanics and finite elements, we demonstrate that plastic deformation of chondrules can occur at low collision velocities of just a few meters per second and with kinetic energies less than tenths of a millijoule when temperatures exceed the glass transition temperature <figure><img></figure>. Conversely, below <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>g</mi></mrow></msub></math></span>, spontaneous chondrule cracking occurs due to differential thermal contraction between phases and is more pronounced in larger chondrules. Counterintuitively, our findings suggest that both ordinary and carbonaceous chondrites formed through similar low-energy processes, with varying degrees of ductility and brittleness depending on the amount of processed material. This implies that the environments where chondrites formed were likely less turbulent and more thermally active than previously thought.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"649 ","pages":"Article 119066"},"PeriodicalIF":4.8,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142706453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Poroelastic effects on rupture propagation across fault stepovers","authors":"Luyuan Huang ,&nbsp;Elías Rafn Heimisson ,&nbsp;Luca Dal Zilio","doi":"10.1016/j.epsl.2024.119103","DOIUrl":"10.1016/j.epsl.2024.119103","url":null,"abstract":"<div><div>The role of poroelasticity in influencing the frequency of ruptures jumping through strike-slip stepovers remains unclear. To understand how poroelastic effects govern long-term rupture behavior in strike-slip fault systems with stepovers, we conduct earthquake sequence simulations incorporating undrained pore pressure responses across the full spectrum of Skempton's coefficient. Our findings reveal that Skempton's coefficient significantly affects the effective normal stress, which can either cause fault clamping or unclamping, and ultimately influences rupture propagation across fault stepovers. The likelihood of rupture jumping is predominantly determined by Skempton's coefficient and the width of the stepover, with Skempton's coefficient showing an approximately linear relationship to the critical jumpable step size. Specifically, a higher Skempton's coefficient facilitates rupture jumping across fault segments, even over larger stepover distances. Analytical solutions involving dislocation and Skempton's coefficient provide practical methods for evaluating pore pressure changes and associated seismic hazards near fault stepovers. Our statistical analysis identifies a critical jumpable width of 4.4–5.1 km due to static stress transfer, assuming a typical range of Skempton's coefficient for compressional stepovers, beyond which ruptures are unlikely to propagate. This study underscores the potential of using physics-based earthquake sequence models to reflect statistical fault rupture behaviors. Given that multi-segment earthquake ruptures present challenges in assessing maximum rupture lengths, our findings offer crucial insights into the role of poroelastic effects and the conditions that facilitate or limit rupture propagation across fault stepovers.</div></div>","PeriodicalId":11481,"journal":{"name":"Earth and Planetary Science Letters","volume":"649 ","pages":"Article 119103"},"PeriodicalIF":4.8,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142706455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}