Tectonophysics最新文献_第3页

Basin development and provenance of the Lower to Middle Jurassic Ban Don Group in Indochina: Implications for the Jurassic Palaeo-Pacific subduction and drainage patterns 印度支那下至中侏罗统班敦群盆地发育与物源：对侏罗纪古太平洋俯冲与排水模式的启示

IF 2.6 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2026-03-18 Epub Date: 2026-01-16 DOI: 10.1016/j.tecto.2026.231081

James W. Handschy , H. Tim Breitfeld , Bui Huy Hoang , Sarah W.M. George , William J. Schmidt , Juliane Hennig-Breitfeld , Michael B.W. Fyhn , Mette Olivarius , Nguyen Quang Tuan , Nguyen Thanh Tung , Do Van Linh , Dinh Quang Sang

Reconstructions of the Mesozoic Palaeo-Pacific are contentious due to significant overprinting during Cenozoic tectonic reorganization in the South China Sea. Here we document rapid (c. 35 myr) basin development, infilling, and pervasive folding of the ∼4 km thick Ban Don Group, an Early to Middle Jurassic basin succession in south-central Vietnam. We address the tectonic significance of the Ban Don Group using sedimentary petrography, detrital zircon geochronology, and structural constraints. Petrography of sedimentary rocks of the Ban Don Group shows mixed recycled orogen character and volcanic arc provenance. Detrital zircon U-Pb geochronology supports sourcing from the Indochina cover units and basement blocks, such as the Kontum Massif, and importantly identifies Jurassic contemporaneous volcanic arc sources. Structural constraints require a phase of pervasive shortening shortly after deposition of the Ban Don Group. Together, these datasets, along with regional tectonic constraints suggest that the Ban Don Group was deposited along a convergent margin, interpreted here as back-arc basin during Early-Middle Jurassic subduction of the Palaeo-Pacific Plate under Indochina. Extension in the Indochina Block was likely a result of a change in the Palaeo-Pacific subduction angle. The NW basin axis of the Ban Don Group is compatible with Early to Middle Jurassic NW-directed back-arc extension and associated NW-dipping subduction. The symmetric shape and orientation of the Ban Don Group salient strongly supports NW Palaeo-Pacific Plate motion in the Late Jurassic. Therefore, NW-dipping subduction of the Palaeo-Pacific Plate during the Jurassic was the driving force for Ban Don Basin subsidence and subsequent shortening.

由于南海新生代构造重组中存在明显的叠印作用，对中生代古太平洋的重建一直存在争议。在这里，我们记录了越南中南部早侏罗世到中侏罗世盆地演代的快速（约35 myr）盆地发育、充填和约4公里厚的Ban Don群的普遍褶皱。本文运用沉积岩相学、碎屑锆石年代学和构造约束等方法探讨了班东群的构造意义。班东群沉积岩的岩石学特征显示出造山带和火山弧的混合物源特征。碎屑锆石U-Pb年代学支持了来自印度支那覆盖单元和基底块体（如Kontum地块）的来源，并重要地确定了侏罗纪同生火山弧的来源。结构约束要求在班敦群沉积后不久出现普遍缩短的阶段。综上所述，结合区域构造约束条件，班东群沉积于辐合边缘，在此被解释为早中侏罗世古太平洋板块在印度支那下的俯冲过程中的弧后盆地。印度支那地块的伸展可能是古太平洋俯冲角变化的结果。班东群的北西向盆地轴与早—中侏罗统北西向弧后伸展和伴随的北西倾俯冲相适应。班东群凸起的对称形状和方位有力地支持了晚侏罗世北西向古太平洋板块运动。因此，侏罗纪时期古太平洋板块的北西倾俯冲是班东盆地沉降和缩短的主要动力。

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引用次数: 0

Crustal seismic structure and stress distribution of Terceira Island, Azores: Insight into the interplay between tectonic and volcanic features 亚速尔群岛Terceira岛的地壳地震结构和应力分布：构造和火山特征之间相互作用的洞察

IF 2.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2026-03-18 DOI: 10.1016/j.tecto.2026.231171

Nuno A. Dias, João Fontiela, Graça Silveira, Mário Moreira, David Schlaphorst, Luís Matias

引用次数: 0

Structural analysis and low-temperature thermochronology of the Ozbak-Kuh Mountains, Central Iran: Constraints on the influence of intraplate strike-slip faulting in the Arabia–Eurasia collision zone 伊朗中部Ozbak-Kuh山脉的构造分析和低温热年代学：对阿拉伯-欧亚碰撞带板内走滑断裂影响的约束

IF 2.6 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2026-03-18 Epub Date: 2026-01-08 DOI: 10.1016/j.tecto.2026.231079

Ali Ghiassi , Ali Yassaghi , Massimiliano Zattin , Saeed Madanipour , Reza Nozaem

Intracontinental deformation in collision zones is generally localized along basement strike-slip fault zones, resulting in crustal shortening and fault-related exhumation of rocks. Strike-slip faulting plays a key role in accommodating crustal deformation in Central Iran, which is located within the active collision zone between the Arabian and Eurasian plates. This study investigates the impact of basement strike-slip faulting on intracontinental deformation of the Central Iran Microcontinent. These deformations are extensively localized in the Kashmar–Kerman Tectonic Zone (KKTZ). Previous U-Pb radiometric dating and thermochronometric studies from the southern parts of the zone have recorded predominantly Early Mesozoic events, whereas the northern parts document Cenozoic events. However, the central part of the zone, in the Ozbak-Kuh Mountains, has remained poorly constrained. Integration of new structural data with low-temperature thermochronometric data from the Ozbak-Kuh Mountains reveals two distinct cooling events. The first event, dated to the Late Cretaceous–Paleocene (∼55–75 Ma), coincided either with the initial closure of the Neo-Tethys Ocean and obduction of its ophiolites, or with the closure of a back-arc basin located to the north. In either scenario, the driving mechanism reflects a convergent tectonic setting characterized by folding of Paleozoic–Mesozoic rocks and deposition of the unconformable Paleocene Kerman Conglomerate. The second cooling event, which occurred during the late Eocene–Oligocene (∼27–37 Ma), is interpreted to mark the onset of continental–continental collision between the Arabian and Eurasian plates, as evidenced by the development of an angular unconformity between Oligocene–Miocene strata and older rock units. This event also led to transpressional deformation along the Kalmard Fault Zone (KFZ). Accelerated cooling in the western parts of the Ozbak-Kuh Mountains, as indicated by apatite fission-track (AFT) data, highlights the significant role of strike-slip faulting in accommodating oblique convergence.

碰撞带的陆内变形一般沿基底走滑断裂带定位，导致地壳缩短和与断层相关的岩石掘出。伊朗中部位于阿拉伯板块和欧亚板块的活动碰撞带内，走滑断裂在调节地壳变形中起着关键作用。本文研究了基底走滑断裂对伊朗中部微大陆陆内变形的影响。这些变形广泛局限于喀什马尔-克尔曼构造带。以前的U-Pb放射性测年和热年代学研究主要记录了早中生代事件，而北部记录了新生代事件。但是，安全区的中心部分，在奥兹巴克-库赫山脉，仍然受到很差的限制。将新的构造数据与来自Ozbak-Kuh山脉的低温热时学数据相结合，揭示了两个不同的冷却事件。第一个事件发生在晚白垩世-古新世（~ 55-75 Ma），与新特提斯洋的初始闭合和蛇绿岩的逆冲相吻合，或者与位于北部的弧后盆地的闭合相吻合。在这两种情况下，驱动机制反映了以古生代-中生代岩石褶皱和不整合的古新世Kerman砾岩沉积为特征的会聚构造环境。第二次冷却事件发生在晚始新世-渐新世（~ 27-37 Ma），这标志着阿拉伯板块和欧亚板块之间大陆碰撞的开始，渐新世-中新世地层与更古老的岩石单元之间形成了角度不整合。这一事件还导致了沿卡尔玛德断裂带（KFZ）的挤压变形。磷灰石裂变径迹（AFT）数据表明，Ozbak-Kuh山脉西部加速冷却，突出了走滑断层在适应斜向辐合中的重要作用。

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引用次数: 0

Deformation microstructures and seismic anisotropy of retrograded eclogites from the Shuanghe, Eastern China 双河退变榴辉岩的变形微结构及地震各向异性

IF 2.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2026-03-13 DOI: 10.1016/j.tecto.2026.231168

Sejin Jung, Haemyeong Jung

引用次数: 0

Understanding the kinematics of the Singhbhum Shear Zone: an integrated approach of anisotropy of magnetic susceptibility and shape preferred orientation 了解singhhumm剪切带的运动学：磁化率各向异性和形状偏好取向的综合方法

IF 2.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2026-03-13 DOI: 10.1016/j.tecto.2026.231169

Swagata Singha, Tridib Kumar Mondal, Susanta Kumar Samanta, Subhabrata Das

引用次数: 0

Paul Tapponnier, deciphering the Earth's crust deformation history in the rocks and landscapes Paul Tapponnier，在岩石和地貌中破译地壳变形历史

IF 2.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2026-03-11 DOI: 10.1016/j.tecto.2026.231166

A. Replumaz, J.-P. Avouac, M.-L. Chevalier, Y. Klinger, C. Lasserre, P.H. Leloup, J. Liu-Zeng, G. Peltzer, J. van der Woerd, X. Xu

引用次数: 0

Assessing fault-earthquake relationships for low-grade seismic sequences (ML < 4.5): examples from the extensional belt of central Italy 评估低级地震序列（ML < 4.5）的断层-地震关系：来自意大利中部伸展带的例子

IF 2.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2026-03-09 DOI: 10.1016/j.tecto.2026.231167

F. Riva, S. Marzorati, D. Latorre, M.R. Barchi

•In Northern Umbria (Central Italy), the area between the Tiber Valley, Gubbio, and the main Apennine ridge is characterized by continuous diffuse microseismicity (ML < 3.0) at a rate of ~3 events/day. Part of this seismicity occurs along the Alto Tiberina Fault (ATF), a 60 km-long low-angle normal fault active since the late Pliocene–early Pleistocene. Within this tectonic setting, we investigate seven low-magnitude seismic sequences (ML < 4.5) that occurred between 2010 and 2023 within the ATF hanging wall. These sequences are not associated with surface-exposed faults, raising questions about the nature and distribution of the seismogenic structures. The main objectives of this study are: (1) to assess whether the seismicity is localized along discrete fault planes or distributed diffusely within fractured rock volumes; and (2) to characterize the geometry and kinematics of the causative faults and evaluate their presence in available 2D seismic reflection profiles. Using a detailed 3D velocity model, we relocated the seismicity and plotted the earthquakes on portions of the depth-converted seismic profiles. Results show that most ruptures occurred along high-angle normal faults branching from the ATF detachment. The geometry of these faults is consistently constrained by both depth-aligned seismicity and the corresponding structures imaged in the seismic reflection profiles, and their kinematic behaviour is coherent with the mainshock. The areas covered by the aftershocks range from 1 to 15 km2, suggesting that the corresponding mainshocks ruptured only portions of larger fault segments. Notably, the behaviour of these minor sequences, in terms of rupture localization and aftershock distribution, closely resembles the patterns observed in larger-magnitude sequences of the same region, highlighting similar seismotectonic processes operating at different scales.

•在北翁布里亚（意大利中部），介于台伯河谷、古比奥和亚平宁主要山脊之间的地区以连续的扩散微地震活动（ML <； 3.0）为特征，频率约为3次/天。部分地震活动发生在上蒂伯里纳断层（ATF）沿线，这是一条60 公里长的低角度正断层，自上新世晚期至更新世早期以来一直活跃。在这一构造背景下，我们研究了2010年至2023年间发生在ATF上盘内的7个低震级地震序列（ML <； 4.5）。这些序列与地表暴露的断层无关，这就提出了发震构造的性质和分布的问题。本研究的主要目的是：(1)评估地震活动性是沿离散断层面局部分布还是在裂隙岩体内弥散分布；(2)描述诱发断层的几何和运动学特征，并在可用的二维地震反射剖面中评估它们的存在。利用详细的三维速度模型，我们重新定位了地震活动性，并在部分深度转换地震剖面上绘制了地震图。结果表明，大部分破裂发生在ATF滑脱分支的高角度正断层上。这些断层的几何形状始终受到深度排列的地震活动性和地震反射剖面中成像的相应结构的约束，它们的运动行为与主震一致。余震覆盖的区域范围为1至15 km2，这表明相应的主震只破坏了较大断层段的一部分。值得注意的是，就破裂定位和余震分布而言，这些小序列的行为与同一地区大震级序列中观察到的模式非常相似，突出了在不同尺度上运行的类似地震构造过程。

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引用次数: 0

Deep electrical structure and tectonic implications of the Yinchuan basin and surrounding areas 银川盆地及周缘深部电性构造及其构造意义

IF 2.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2026-03-09 DOI: 10.1016/j.tecto.2026.231140

Jingyuan Wang, Letian Zhang, Wuxu Peng, Duowen Zhu, Chen Qi, Jinxin Chang

The Yinchuan Basin is located in the northern segment of the north-south tectonic belt formed by the collision between the Alxa and Ordos blocks. This region experiences intense extensional activity and was the site of the 1739 Pingluo M8.0 earthquake. To investigate the deep structure of the study area and its relationship with seismic activity, this study employed magnetotelluric sounding data covering the Yinchuan Basin and its surrounding areas to perform a three-dimensional inversion, obtaining a high-resolution electrical structure model of the upper mantle scale. Analysis indicates: the western margin of the Ordos Block exhibits a “low-high-low” layered resistivity distribution, while its northwestern margin retains a stable, high-resistivity crustal structure. The Helan Mountains possess a thick, high-resistivity “mountain root”. Beneath the Yinchuan-Hetao Basin, there exist extensive, ribbon-like low-resistivity bodies extending into the upper mantle, distributed in NE and NWW trends at depth. The resistivity model reveals significant lithospheric modification and thinning in the study area. We propose that the influence of the northeastward expansion of the Tibetan Plateau has reached the Yinchuan–Hetao Basin. Superimposed on the far-field stress effects of the Paleo-Pacific Plate subduction, this has led to extensive modification and partial melting of the mantle and lower crust beneath the western margin of the Ordos Block. One portion of the modified material continues to migrate northeastward, while another portion undergoes dehydration and ascends along the weakened rift basins. The interaction between fluid-rich, low-resistivity bodies and rigid, high-resistivity rocks generates stress accumulation, leading to crustal rupture. This is one of the reasons for the frequent seismicity in the study area.

银川盆地位于阿拉善地块与鄂尔多斯地块碰撞形成的南北构造带北段。该地区经历了强烈的伸展活动，是1739年平洛8.0级地震的发生地。为研究研究区深部构造及其与地震活动的关系，利用覆盖银川盆地及周边地区的大地电磁测深资料进行三维反演，获得了高分辨率的上地幔尺度电性结构模型。分析表明：鄂尔多斯地块西缘呈现“低-高-低”的层状电阻率分布，而西北缘则保持稳定的高电阻率地壳结构。贺兰山具有厚而高电阻率的“山根”。在银川-河套盆地下方，广泛存在延伸至上地幔的带状低阻体，在深部呈NE和NWW向分布。电阻率模型显示研究区岩石圈有明显的改造和减薄。青藏高原东北扩张的影响已延伸至银川-河套盆地。加之古太平洋板块俯冲的远场应力作用，导致鄂尔多斯地块西缘地幔和下地壳发生了广泛的变质和部分熔融作用。一部分变质物质继续向东北移动，而另一部分则经历脱水并沿弱裂陷盆地上升。富流体、低电阻率体与刚性、高电阻率岩石之间的相互作用产生应力积聚，导致地壳破裂。这是研究区地震活动频繁的原因之一。

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引用次数: 0

Plate motion drivers: Geodynamical framework and statistical appraisal for the case of the Neogene Nazca–South America convergence 板块运动驱动因素：新近纪纳斯卡-南美辐合带的地球动力学框架和统计评价

IF 2.6 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2026-03-06 Epub Date: 2026-01-17 DOI: 10.1016/j.tecto.2026.231095

Valentina Espinoza , Juan Martin de Blas , Ingo L. Stotz , Andrés Tassara Oddo , Giampiero Iaffaldano

Recent high-resolution reconstructions of plate motions reveal a complex history of alternating slowdowns and speedups, often over short timescales (

<

5 Myr). These rapid changes offer an opportunity to reassess the geodynamic processes driving tectonic plates, which we explore using an analytical inverse framework. This approach, however, inevitably yields non-unique solutions when inferring the forces behind a motion change. We partly address this issue by focusing on forces capable of varying at rates consistent with rapid kinematic shifts, though the specific driver behind any change may remain ambiguous. We adopt a two-step methodology, using torque changes as intermediaries linking force variations to reconstructed absolute plate-motion changes. First, we employ an established method that combines rheological constraints with torque-balance principles to estimate the torque variation required for a given kinematic change. Second, we estimate torque-change vectors arising from a broad range of geodynamic scenarios — acting at plate boundaries (e.g., slab pull, interplate friction) and at the base of plates (e.g., asthenospheric flow). We then apply directional statistics to quantify the similarity between the motion-based torque-change distribution and each simulated vector. This comparison allows us to identify the location and direction of the force-change vectors most likely to produce the motion change of study. We apply this method to the Neogene Nazca–South America convergence. Our kinematic analysis reveals rapid slowdowns in the absolute motion of both plates and a pronounced Nazca speedup at

\sim

10–12 Myr. Our geodynamic analysis indicates that the force variations driving the slowdowns are likely concentrated along the central segments of the shared convergent boundary. This result aligns with established hypotheses linking reduced convergence to Central Andes orogeny, thereby supporting our approach. Key advantages of this novel method include fast computation, explicit treatment of kinematic uncertainties, and broad applicability across tectonic settings.

最近对板块运动的高分辨率重建揭示了一个复杂的减速和加速交替的历史，通常在短时间尺度上（<5 Myr）。这些快速变化为重新评估驱动构造板块的地球动力学过程提供了机会，我们使用解析逆框架进行了探索。然而，在推断运动变化背后的力量时，这种方法不可避免地会产生非唯一的解决方案。我们通过关注能够以与快速运动变化一致的速率变化的力来部分解决这个问题，尽管任何变化背后的具体驱动因素可能仍然不明确。我们采用两步方法，使用扭矩变化作为中介连接力变化重建绝对板块运动的变化。首先，我们采用一种将流变约束与扭矩平衡原理相结合的既定方法来估计给定运动变化所需的扭矩变化。其次，我们估计了由广泛的地球动力学情景引起的扭矩变化矢量-作用于板块边界（例如，板块拉力，板块间摩擦）和板块底部（例如，软流圈流）。然后，我们应用方向统计来量化基于运动的转矩变化分布与每个模拟矢量之间的相似性。这种比较使我们能够确定最有可能产生研究运动变化的力变化向量的位置和方向。我们将此方法应用于新近纪纳斯卡-南美辐合带。我们的运动学分析显示，两个板块的绝对运动都迅速减速，在~ 10-12迈时出现了明显的纳斯卡加速。我们的地球动力学分析表明，驱动减速的力变化可能集中在共同辐合边界的中心部分。这一结果与既定的假设相一致，将减少收敛与安第斯山脉中部造山运动联系起来，从而支持我们的方法。这种新方法的主要优点包括快速计算，明确处理运动不确定性，以及在构造环境中的广泛适用性。

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引用次数: 0

The Hainan plume and the origin of tectonic and magmatic activity in Southeast Asia 海南羽流与东南亚构造岩浆活动的起源

IF 2.6 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Tectonophysics

Pub Date : 2026-03-06 Epub Date: 2026-01-16 DOI: 10.1016/j.tecto.2026.231087

Rupak Banerjee , Chujie Liu , Stephen P. Grand , Eric Sandvol , Supriyo Mitra , Xiaofeng Liang , Shengji Wei

Southeast Asia hosts widespread Cenozoic intraplate volcanism that is not related to arc volcanism or to the opening of the South China Sea. In this study, we analyze the Southeast Asia portion of the recently developed full waveform seismic model, FWEA23, presenting its first comprehensive interpretation for this region. We observe slow shear velocity (Vs) anomalies (∼4–5%) extending to ∼660 km depth beneath Hainan island, resembling one or more plume-like upwellings. At depths <220 km, the slow anomaly extends westward to the Sagaing fault, eastward to the subduction zones, and northward to ∼26°N latitude. This lateral spreading explains the similarities in timing and geochemical signature between the Cenozoic intraplate volcanism and the Hainan volcano. We observe that the asthenospheric mantle (100–220 km) beneath Southeast Asia is ∼1.4% slower than the global average shear velocity of oceanic asthenosphere, implying that the mantle beneath Southeast Asia is warmer than the global adiabat. We also detect high Vs anomalies (up to ∼3%) in the mantle transition zone, resembling lithospheric slab fragments which trap heat and may have facilitated plume initiation through the slab gaps. Additionally, we present evidence from radial anisotropy (> + 3%), which reveals strong horizontal mantle flow (<200 km) away from the Hainan plume. This is consistent with lateral plume-head spreading, and associated lithospheric thinning across Southeast Asia. Our results provide new constraints on mantle dynamics of Southeast Asia by (i) highlighting the super-adiabatic character of the asthenosphere, (ii) a slab-induced mechanism for Hainan plume generation and (iii) the genesis of the intraplate volcanism.

东南亚存在广泛的新生代板内火山活动，但与弧火山活动或南海的开口无关。在这项研究中，我们分析了最近开发的全波形地震模型FWEA23的东南亚部分，首次对该地区进行了全面解释。我们观察到海南岛下方延伸至~ 660 km深度的慢剪切速度（Vs）异常（~ 4-5%），类似于一个或多个羽状上升流。在深度220 km处，缓慢异常向西延伸至实皆断层，向东延伸至俯冲带，向北延伸至~ 26°N纬。这种横向扩张解释了新生代板内火山活动与海南火山在时间和地球化学特征上的相似性。我们观察到东南亚软流圈地幔（100-220 km）比全球海洋软流圈平均剪切速度慢约1.4%，这意味着东南亚软流圈地幔比全球绝热层温暖。我们还在地幔过渡带中发现了高Vs异常（高达~ 3%），类似于岩石圈板块碎片，它们捕获热量，并可能通过板块间隙促进了地幔柱的形成。此外，我们从径向各向异性（> + 3%）中得到证据，表明海南地幔柱外有强烈的水平地幔流（<200 km）。这与整个东南亚的横向羽状顶扩张和岩石圈变薄相一致。我们的研究结果通过(i)强调软流圈的超绝热特征，（ii）海南羽流形成的板块诱发机制和（iii）板内火山作用的成因，为东南亚地幔动力学提供了新的约束。

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引用次数: 0