Tectonophysics最新文献

Crust and upper mantle structures of the North China Craton from Eikonal tomography and shear velocity inversion

IF 2.7 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2025-03-02 DOI: 10.1016/j.tecto.2025.230682

Yu Geng, Qingju Wu, Yonghua Li, Ruiqing Zhang

Using the vertical component seismograms of 1583 events recorded by 1712 broadband stations in the SeisDmc and the ChinArray projects, Rayleigh wave phase velocities at 20–160 s periods of the North China Craton were estimated through Eikonal tomography. Phase velocities at 8–50 s periods and group velocities at 10–140 s periods from previous studies were included as an augmentation of our Rayleigh wave velocities dataset. The dispersion curves for phase and group velocities were inverted together for a 3-D Vs model. Our model demonstrates remarkable variations in crustal thicknesses and upper mantle velocities from the west to the east, indicating different evolutionary processes since the Cenozoic rejuvenation. Significant lateral inhomogeneities in the Trans-North China Orogen suggest that the lithosphere under the central segment is less modified during the Phanerozoic than that below the rest portions. The low velocities in the upper mantle below Datong volcanoes may originate from a hot upwelling of asthenospheric materials associated with a rifting process under the northeast margin of Ordos. Our model supports the inference that the southern and northern parts of the Weihe-Shanxi Rift System are experiencing different rifting mechanisms. The southern part experienced a long history of extension and complicated rifting processes triggered by the early uplift of the Tibetan plateau. The opening of the northern segment is a combined effect of ongoing asthenospheric upwelling and the anticlockwise rotation of the Ordos block.

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引用次数: 0

The reservoir-induced 2023 Heyuan earthquake sequence in Guangdong, China and its geodynamic implications

IF 2.7 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2025-02-26 DOI: 10.1016/j.tecto.2025.230681

Huimin Guan , Jianshe Lei , Dapeng Zhao , Xiaohui Hu

To better understand the mechanism of the 2023 M4.3 Heyuan earthquake sequence, we relocate the events of this sequence during January to August 2023 and determine a focal mechanism solution of the Heyuan mainshock. A total of 565 events including the mainshock are precisely relocated using the double-difference location method. Our results show that most of the events occurred in the Shijiao-Xingang-Baitian fault zone with focal depths of 7–13 km, and the aftershocks took place above the mainshock hypocenter. This sequence has obvious spatiotemporal distribution features. Before the mainshock, the seismicity was low, but within 1.5 h following the mainshock, the sequence extended toward a shallow depth and bounced back and forth in the east-west direction. Between 1.5 and 8 h after the mainshock, the sequence gradually converged to the Shijiao-Xingang-Baitian fault. After 8 h the sequence gradually extended to the eastern part of the fault. To further ascertain the seismogenic fault, we invert waveform data for the mainshock focal mechanism. Our result shows that the Heyuan earthquake had a left-lateral normal rupture with M_W 4.1 and a focal depth of 9.8 km. The strike, dip, and rake angles of nodal plane I are 334°, 64°, and − 58°, whereas those of nodal plane II are 99°, 40°, and − 137°. Among the existing faults in the study area, the strike of nodal plane I is closer to that of the Shijiao-Xingang-Baitian fault, which could be the seismogenic fault. In addition, seismic tomography revealed a high-Vp/Vs anomaly in the Heyuan earthquake area, suggesting that the Xinfengjiang Reservoir infiltration can explain why the aftershocks spread eastward. These results indicate that the 2023 Heyuan earthquake sequence is related to the seepage of the Xingfengjiang Reservoir water leading to the local crustal stress field variation, which is helpful to understand the mechanism of reservoir-induced earthquakes worldwide.

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引用次数: 0

Areal strain responses to Lamb waves generated from 2022 Hunga-Tonga volcano eruption

IF 2.7 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2025-02-22 DOI: 10.1016/j.tecto.2025.230677

Xin Zhang , Angelo De Santis , Gianfranco Cianchini , Xiaohui Li , Yuanmin Huang , Xuan Yang , Xiaoping Wu

On 15 January 2022, the largest Hunga-Tonga volcano eruption ever recorded produced a plume, causing atmospheric waves that propagated from the volcanic epicenter to the surrounding areas. Although studies have reported multi-parameter responses to this eruption, the far-field areal strain on the surface remained underexplored. Here we adopted 7 parameters of the strain tensors in the far-field about 8700–13,500 km from the volcano epicenter to study their responses to the generated Lamb waves from the eruption. The results showed that at least triple perturbations could be picked up clearly from the strain curves, indicating Lamb waves propagated several times around the globe from opposite directions at the same speed of approximately 320 m/s, each lasting about 30.5 h. For the surface shear strain, we rotated the coordinates system to the radial and tangential direction of Lamb wave propagation, and found that the amplitude of the radial strain was twice that of the tangential strain. Additionally, the principal strain reflected by the Mohr strain circles is consistent with the propagation direction of Lamb waves. The results indicate that the volcano eruption caused fluctuations via the air-rock interaction induced by Lamb waves in the air.

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引用次数: 0

Evidence of active faulting obtained by the waveform inversion of the seismic moment tensor and InSAR analysis in Northeastern Mexico: El Corcovado seismic sequence of May to August 2023

IF 2.7 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2025-02-21 DOI: 10.1016/j.tecto.2025.230668

Juan C. Montalvo-Arrieta , Jorge A. Salinas-Jasso , Víctor H. Espíndola , Luis G. Ramos-Zuñiga , Juan A. Ramírez-Fernández

The first recorded moderate-intensity mainshock and largest aftershock in the boundary between the Basin and Range and Sierra Madre Oriental provinces are presented. This seismological evidence demonstrates the presence of active faulting in northeastern Mexico. We estimated seismic source parameters and surface deformation related to a low-moderate seismic sequence that occurred from May 11 to August 2, 2023 (3.4 ≤ M_d ≤ 5) in the limits of the San Luis Potosí, Nuevo León and Tamaulipas states through waveform inversion of the seismic moment tensor and InSAR analysis. The event of May 16, 2023 (M_d 5.0, M_w 4.92) is the biggest earthquake instrumentally recorded in this region. The mainshock and the largest aftershock (June 5, 2023; M_d 4.9, M_w 4.86) earthquakes were well-recorded over 100–330 km by broadband stations installed in central and northeastern Mexico. Here, it is suggested that both earthquakes were associated with the rupture of El Corcovado normal fault. We estimated a rupture area of approximately 11 km² with an average displacement of 7 cm. Fault plane solutions of the mainshock were strike 358°, dip 39°, rake −90°, and Mo 2.685e+16 Nm. El Corcovado fault is associated with a set of normal faults NNW-SSE trending located along the boundary between the Basin and Range and the Sierra Madre Oriental provinces. Such considerations lead to a review of the neotectonic setting of northeastern Mexico and the associated seismic hazard assessment.

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引用次数: 0

Bathymetric and structural insights into the Islas Marías Archipelago, Mexico, and surrounding areas

IF 2.7 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2025-02-21 DOI: 10.1016/j.tecto.2025.230669

Felipe de Jesús Escalona-Alcázar , Francisco Javier Núñez-Cornú , Diana Núñez , Diego Córdoba-Barba

The Islas Marías Archipelago is located south of the Gulf of California. This study presents a structural geologic analysis of María Madre Island, coupled with a detailed bathymetric survey of the surrounding area. Our goal is to delineate the deformation geometry and identify new morphostructural features in the region. Bedding tilting coincided with normal faulting of the lower member of the Ojo de Buey sequence, likely at the end of the Pliocene or the beginning of the Pleistocene, associated with the early stage of the Gulf of California rifting. Seismic reflection profiles from previous studies indicate that the West Ranges are within a thinned continental crust, structurally controlled by the María, Magdalena, and South Magdalena faults. Furthermore, a detailed bathymetric survey and orthoimages from the islands revealed structural lineaments in both oceanic and continental crust. In the continental crust, these lineaments have a preferred orientation between 050° to 090°, similar to the faulting trend on María Madre Island. However, they are oblique to those in the oceanic crust and mainland Mexico. We propose that María Madre Island may have undergone a 50° clockwise rotation. If we apply a counterclockwise rotation of this magnitude to the faults and lineaments in the continental crust of the archipelago and the region west of it, their preferred orientation becomes parallel to the Tamayo Fracture Zone in the oceanic crust, the San Blas fault within the continental shield and, the Tepic-Zacolaco rift extending eastward into mainland Mexico. This suggests that rotation affected the continental crust, either west of Puerto Vallarta, in the archipelago, or the West Ranges, while the oceanic crust remained relatively unaffected. We propose the term “Islas Marías Block” to designate a fragment of continental crust encompassing the archipelago and the West Ranges, which share a common deformation style.

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引用次数: 0

Local seismicity along the Olenek Sector of the Lena-Anabar suture, SW Laptev Sea Rift System – Rift-related or reactivation of the former passive margin of the Siberian Craton?

IF 2.7 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2025-02-20 DOI: 10.1016/j.tecto.2025.230676

A. Plötz , A. Krylov , W.H. Geissler , S. Shibaev , F. Krüger , C. Haberland , B. Baranov , R. Tuktarov , N. Tsukanov , M. Novikov

The Laptev Sea region in Northeast Siberia is one out of very few examples for possible initiation of continental breakup. In the North seismicity concentrates along the Gakkel Ridge separating the oceanic parts of the North American and Eurasian plates. Earthquake epicenters are more diffuse on the Laptev Sea Shelf and further inland, where in 1927 two M6.7 earthquakes occurred just 200 km to the South of the seaport of Tiksi. Suspicious hypocenter depths of up to 80 km have been reported from short temporary deployments near the coast. Following reconnaissance investigations in 2015, we installed one detection array near Tiksi in summer 2016 as a joint Russian-German initiative. In addition, a temporary network of 12 stations were deployed by ship along major river branches within the Lena Delta to the west of Tiksi.

Here we report on seismicity from the first observation period from late July 2016 till May 2017. The analysis of more than 500 local and regional earthquakes show, that focal depths extend to about 30 km within the lower crust, but we could not find evidence for earthquakes in the uppermost mantle beneath our seismological network. Local magnitudes mL range from −0.9 to 3.7 during our observation period. Furthermore, a local 1D seismic velocity model is derived from the data that was used for the location of the earthquakes. Several earthquake swarm-like sequences or earthquake bursts occurred throughout the observation period. Focal mechanisms of the small-magnitude earthquakes are not conclusive, but hint to a partly transpressional regime in the study area.

西伯利亚东北部的拉普捷夫海地区是可能引发大陆断裂的极少数例子之一。在北部，地震集中在分隔北美板块和欧亚板块海洋部分的加克尔海脊沿线。地震震中在拉普捷夫海大陆架和更远的内陆地区较为分散，1927 年在提克希海港以南仅 200 公里处发生了两次 M6.7 级地震。据报告，在海岸附近的短时间临时部署的疑似次中心深度可达 80 千米。继 2015 年的侦察调查之后，我们于 2016 年夏季在提克希附近安装了一个探测阵列，这是俄罗斯和德国的一项联合举措。此外，我们还在蒂克西以西的勒拿河三角洲内的主要河流支流沿岸用船部署了由 12 个台站组成的临时网络。在此，我们报告了 2016 年 7 月底至 2017 年 5 月第一个观测期的地震情况。对 500 多次地方和区域地震的分析表明，地壳下部的焦点深度延伸至约 30 千米，但我们无法在我们的地震网络下找到最上地幔地震的证据。在我们的观测期间，当地的震级 mL 从 -0.9 到 3.7 不等。此外，我们还从用于地震定位的数据中推导出了一个本地一维地震速度模型。在整个观测期间，发生了几次类似地震群的地震序列或地震爆发。小震级地震的震源机制尚无定论，但暗示研究区域存在部分换能机制。

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引用次数: 0

Influence of horizontal stress ratio on frictional stability of fault under true triaxial stress conditions

IF 2.7 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2025-02-20 DOI: 10.1016/j.tecto.2025.230678

Zhiming Liang , Zhenyu Zhang , Haoran Dou , Shengpeng Hao

To understand the fault friction stability and seismic mechanisms under in-situ stress conditions of the Earth's crust, the rectangular prismatic rock sample with a sawcut fault inclined at an angle of 29° to the axis is introduced to withstand the three stress components of true triaxial stress conditions (vertical stress σ_v, horizontal stress σ_h, and stress parallel to the strike of the fault plane σ_p). Velocity-stepping experiments are performed on the sawcut faults to investigate fault frictional behavior and slip stability under different σ_h/σ_p ratios and stress σ_p within the rate-and-state framework. Results indicate that increasing σ_h/σ_p ratios decrease the frictional velocity-dependent parameter (a-b), exhibiting a transition from velocity-strengthening to velocity-weakening behaviors. Shallow grooves develop along the fault surface and act as stress barriers at the low σ_h/σ_p ratio. With increasing σ_h/σ_p ratios, the fault surface gradually converges to uniform smoothness due to asperity abrasion, suggesting that the weakening effect of increasing σ_h/σ_p ratios on fault stability is related to stress redistribution. The enhanced fault critical stiffness (K_c) with increasing σ_h/σ_p ratios promotes fault instability nucleation. Our results reveal that true triaxial in-situ stress states in seismogenic zones exert significant control on frictional behavior and fault stability.

为了解地壳原位应力条件下的断层摩擦稳定性和地震机制，引入了与轴线成 29°角倾斜的锯切断层矩形棱柱岩样，以承受真实三轴应力条件下的三个应力分量（垂直应力 σv、水平应力 σh 和平行于断层面走向的应力 σp）。在锯切断层上进行了速度步进实验，以研究在速率-状态框架内不同 σh/σp 比值和应力 σp 条件下的断层摩擦行为和滑移稳定性。结果表明，σh/σp 比值增大会降低摩擦速度相关参数 (a-b)，表现出从速度增强到速度减弱的过渡行为。沿断层表面形成浅槽，在低σh/σp 比时充当应力屏障。随着σh/σp比值的增加，断层表面会因表面磨损而逐渐趋于均匀光滑，这表明σh/σp比值的增加对断层稳定性的削弱作用与应力再分布有关。随着σh/σp比率的增加，断层临界刚度（Kc）增强，从而促进了断层不稳定性的成核。我们的研究结果表明，震源区真实的三轴原位应力状态对摩擦行为和断层稳定性具有重要的控制作用。

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引用次数: 0

Interplay of slow-slip faults beneath Mexico City induces intense seismicity over months

IF 2.7 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2025-02-16 DOI: 10.1016/j.tecto.2025.230659

Manuel J. Aguilar-Velázquez , Paulina Miranda-García , Víctor M. Cruz-Atienza , Darío Solano-Rojas , Josué Tago , Luis A. Domínguez , Carlos Villafuerte , Víctor H. Espíndola , Delia Bello-Segura , Luis Quintanar-Robles , Mathieu Perton

In February 2023, a long seismic sequence began in western Mexico City causing widespread panic and some damage to housing infrastructure. On May 11 and December 14, two Mw3.2 mainshocks occurred at less than 700 m depth. Unprecedented satellite interferograms captured tectonic deformations in the two epicentral zones during the days surrounding the earthquakes. Data analysis revealed extended slip with maximum values around 8 cm on two sub-parallel east-west trending normal faults 800 m apart: namely the Barranca del Muerto (BM) fault to the south and the Mixcoac fault to the north. Detailed microseismicity analysis showed that 95 % of the slip on the BM fault was aseismic and initiated at least 6 days before the May 11 earthquake on the main asperity, located 1 km east of the hypocenter and ∼ 1.2 km deep. For the December event on the Mixcoac fault, ∼70 % of the slip was also aseismic but shallower (mostly above 600 m), which can be partially explained by the induced stresses on that fault due to the May slip on the BM fault. A quantitative geomorphological analysis allowed to establish the structural connection between both buried faults and their geomorphic expression to the west, with surface extensions of ∼3.5 and ∼ 4.5 km in the hilly area—where the most intense seismicity concentrates. The spatiotemporal patterns of fast and slow earthquakes suggest that the seismotectonics west of the city comprises two mechanically distinct zones: a stable region prone to aseismic deformation to the east where faults are buried under water-saturated sediments, and an unstable region to the west, prone to seismic radiation where faults are expressed geomorphologically. Thus, the seismic swarms in this area appear to result from the regional extensional regime, the stresses induced by slow slip on the eastern fault segments and interaction between these faults.

{"title":"Interplay of slow-slip faults beneath Mexico City induces intense seismicity over months","authors":"Manuel J. Aguilar-Velázquez , Paulina Miranda-García , Víctor M. Cruz-Atienza , Darío Solano-Rojas , Josué Tago , Luis A. Domínguez , Carlos Villafuerte , Víctor H. Espíndola , Delia Bello-Segura , Luis Quintanar-Robles , Mathieu Perton","doi":"10.1016/j.tecto.2025.230659","DOIUrl":"10.1016/j.tecto.2025.230659","url":null,"abstract":"<div><div>In February 2023, a long seismic sequence began in western Mexico City causing widespread panic and some damage to housing infrastructure. On May 11 and December 14, two Mw3.2 mainshocks occurred at less than 700 m depth. Unprecedented satellite interferograms captured tectonic deformations in the two epicentral zones during the days surrounding the earthquakes. Data analysis revealed extended slip with maximum values around 8 cm on two sub-parallel east-west trending normal faults 800 m apart: namely the Barranca del Muerto (BM) fault to the south and the Mixcoac fault to the north. Detailed microseismicity analysis showed that 95 % of the slip on the BM fault was aseismic and initiated at least 6 days before the May 11 earthquake on the main asperity, located 1 km east of the hypocenter and ∼ 1.2 km deep. For the December event on the Mixcoac fault, ∼70 % of the slip was also aseismic but shallower (mostly above 600 m), which can be partially explained by the induced stresses on that fault due to the May slip on the BM fault. A quantitative geomorphological analysis allowed to establish the structural connection between both buried faults and their geomorphic expression to the west, with surface extensions of ∼3.5 and ∼ 4.5 km in the hilly area—where the most intense seismicity concentrates. The spatiotemporal patterns of fast and slow earthquakes suggest that the seismotectonics west of the city comprises two mechanically distinct zones: a stable region prone to aseismic deformation to the east where faults are buried under water-saturated sediments, and an unstable region to the west, prone to seismic radiation where faults are expressed geomorphologically. Thus, the seismic swarms in this area appear to result from the regional extensional regime, the stresses induced by slow slip on the eastern fault segments and interaction between these faults.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"902 ","pages":"Article 230659"},"PeriodicalIF":2.7,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mapping a seismic barrier across the Shumagin Gap from satellite goce derivatives direct and inverse modeling

IF 2.7 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2025-02-15 DOI: 10.1016/j.tecto.2025.230657

Orlando Álvarez , Silvana Spagnotto , Silvina Nacif , Mario Gimenez , Andrés Folguera

The earthquake potential of the segment known as the Shumagin gap, located along the southwestern Alaska convergent margin, has been debated for over 40 years. This portion of the megathrust has not experienced a historically great earthquake with a magnitude (Mw) greater than Mw = 8.0, or at least none has been recorded in the instrumental era, exhibiting a moderate to low slip deficit. On 22 July 2020, an Mw = 7.8 thrust-fault earthquake ruptured a deeper portion of the megathrust along the eastern edge of the Shumagin Gap. Aftershocks following this event, including an Mw = 7.6 strike-slip earthquake on 19 October 2020, delineated an approximate north-south fault zone. Later, on 29 July 2021, an Mw = 8.2 thrust-fault earthquake ruptured the Semidi segment to the East. In this work, we examined the coseismic behavior of the Shumagin gap and adjacent Semidi segment along the Alaska margin from direct and inverse models obtained from satellite-derived gravity data. The distribution of the vertical gravity gradient shows a saddle point topography along the Shumagin Gap where the aftershocks of the July 2020 Mw = 7.8 earthquake concentrated in a nest. The gravity disturbance and the inverse model of mass anomalies also show an along-strike segmentation. Anomalous mass inferred along the Shumagin Gap, is consistent with the seismicity, focal mechanisms, and recently published works, suggesting that this segment hosts a seismic barrier (along-strike) that limits earthquakes with magnitudes Mw > 8.0. On the other hand, an across-strike (along-dip) segmentation is inferred from Tzz, which is consistent with vertical motion models. Comparison of the interplate coupling and b-values distribution to the vertical gravity gradient, allowed mapping main asperities in the region suggesting that the area to the west of the Shumagin gap could host a great megathrust earthquake in the future.

{"title":"Mapping a seismic barrier across the Shumagin Gap from satellite goce derivatives direct and inverse modeling","authors":"Orlando Álvarez , Silvana Spagnotto , Silvina Nacif , Mario Gimenez , Andrés Folguera","doi":"10.1016/j.tecto.2025.230657","DOIUrl":"10.1016/j.tecto.2025.230657","url":null,"abstract":"<div><div>The earthquake potential of the segment known as the Shumagin gap, located along the southwestern Alaska convergent margin, has been debated for over 40 years. This portion of the megathrust has not experienced a historically great earthquake with a magnitude (Mw) greater than Mw = 8.0, or at least none has been recorded in the instrumental era, exhibiting a moderate to low slip deficit. On 22 July 2020, an Mw = 7.8 thrust-fault earthquake ruptured a deeper portion of the megathrust along the eastern edge of the Shumagin Gap. Aftershocks following this event, including an Mw = 7.6 strike-slip earthquake on 19 October 2020, delineated an approximate north-south fault zone. Later, on 29 July 2021, an Mw = 8.2 thrust-fault earthquake ruptured the Semidi segment to the East. In this work, we examined the coseismic behavior of the Shumagin gap and adjacent Semidi segment along the Alaska margin from direct and inverse models obtained from satellite-derived gravity data. The distribution of the vertical gravity gradient shows a saddle point topography along the Shumagin Gap where the aftershocks of the July 2020 Mw = 7.8 earthquake concentrated in a nest. The gravity disturbance and the inverse model of mass anomalies also show an along-strike segmentation. Anomalous mass inferred along the Shumagin Gap, is consistent with the seismicity, focal mechanisms, and recently published works, suggesting that this segment hosts a seismic barrier (along-strike) that limits earthquakes with magnitudes Mw > 8.0. On the other hand, an across-strike (along-dip) segmentation is inferred from Tzz, which is consistent with vertical motion models. Comparison of the interplate coupling and <em>b-values</em> distribution to the vertical gravity gradient, allowed mapping main asperities in the region suggesting that the area to the west of the Shumagin gap could host a great megathrust earthquake in the future.</div></div>","PeriodicalId":22257,"journal":{"name":"Tectonophysics","volume":"900 ","pages":"Article 230657"},"PeriodicalIF":2.7,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143444750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessment of uncertainty propagation within compaction-based exhumation studies using Bayesian inference

IF 2.7 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2025-02-15 DOI: 10.1016/j.tecto.2025.230660

Patrick Makuluni , Juerg Hauser , Stuart Clark

Exhumation plays a crucial role in shaping the evolution and distribution of resource systems in sedimentary basins, affecting mineral and energy resource exploration. Accurate exhumation estimates, derived primarily from empirical equations based on compaction and thermal datasets, are essential but are often compromised by data errors and unquantified uncertainties in model parameters. For instance, model parameters are usually assumed not to be affected by uncertainties despite varying within measurable ranges. Uncertainties from such variation can propagate and compromise the accuracy of exhumation estimates.

This study introduces a novel and refined approach to exhumation estimation using Markov Chain Monte Carlo (MCMC) methods to quantify and address uncertainties in data and model parameters. Using this approach, we developed a workflow for quantifying exhumation magnitudes and their associated uncertainties and applied it to sonic log datasets from the Canning and Bonaparte Basins. The impact of uncertainty propagation on exhumation results was assessed by examining four scenarios: assuming no uncertainty in the model or data, considering data noise without model uncertainty, considering model uncertainty without data noise, and considering model uncertainties and data noise together.

Our study yielded robust exhumation estimates in the Canning and Bonaparte Basins. Comparison with previous studies shows similarities and differences in exhumation estimates for multiple episodes, with discrepancies potentially arising from variations in exhumation models, data quality and coverage. Uncertainty propagation analysis reveals that considering data-related and model uncertainties together produces variable distributions of exhumation estimates with wider uncertainty ranges. Overall, data quality and coverage proved more critical for the accuracy and precision of exhumation estimates than model refinement. Our models can be integrated into basin evolution studies, help refine fluid migration models, and improve understanding of sedimentation and ore preservation to optimise resource exploration in sedimentary basins.

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引用次数: 0