Physics of the Earth and Planetary Interiors最新文献_第4页

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2026-01-01

引用次数: 0

On the global centroid moment tensor achievements and the next generation earthquake catalogs 全球质心矩张量研究成果与下一代地震目录

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2025-12-23 DOI: 10.1016/j.pepi.2025.107490

T.-S. Phạm, H. Tkalčić, J. Hu, Z. Wei

The systematic determination of the source characteristics of global earthquakes and other seismic sources in a robust and consistent manner is a paramount task in seismology. The Global Centroid Moment Tensor (GCMT) project (Ekström et al., 2012), employing an elegant inversion approach and thoughtful data selection, has been a standard bearer for such an autonomous earthquake catalog. This, by no means an all-encompassing review, celebrates the long-lasting impact and legacy it has left on the seismological and broader Earth science community, from tectonics and structural geology to geodesy and hazard assessment. We also identify and discuss three areas that, in our view, are subject to potential improvement in the current GCMT practice. These include (i) enhanced quantification of uncertainty in MT solutions, (ii) utilization of 3D Earth models, and (iii) robust development of dynamic models that extend beyond a point source assumption in time and space. Recent developments in various areas of theoretical and observational seismology, such as advances in Bayesian inversion, 3D waveform modeling, and applied machine learning methods, will enable the integration of these needed elements into the next generation of routine earthquake catalogs.

以稳健和一致的方式系统地确定全球地震和其他震源的震源特征是地震学中的一项重要任务。全球质心矩张量（GCMT）项目（Ekström等人，2012）采用了一种优雅的反演方法和周到的数据选择，已经成为这种自主地震目录的标准承担者。这绝不是一篇无所不包的评论，它赞扬了它在地震学和更广泛的地球科学界留下的长期影响和遗产，从构造学和结构地质学到大地测量学和危害评估。我们还确定并讨论了我们认为当前GCMT实践中有待改进的三个领域。这些措施包括(i)加强MT解决方案不确定性的量化，（ii） 3D地球模型的利用，以及（iii）在时间和空间上超越点源假设的动态模型的稳健发展。理论和观测地震学各个领域的最新发展，如贝叶斯反演、三维波形建模和应用机器学习方法的进展，将使这些必要的元素整合到下一代常规地震目录中。

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引用次数: 0

Determining the density of different regions of Peninsular India and analyzing the deep crustal structure beneath the Saurashtra peninsula using the fractal method 用分形方法测定印度半岛不同区域的密度，分析索拉斯特拉半岛下的深部地壳结构

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2025-12-17 DOI: 10.1016/j.pepi.2025.107489

Swarnapriya Chowdari, Bijendra Singh

In regional geodynamic studies, Bouguer anomalies are invaribly computed using a slab density of 2.67 g/cm³. However, fractal approach can be used to estimate the factual density of the Bouguer slab. In this study, we deployed fractal method to calculate the Bouguer slab density for several tectonic regions in Peninsular India such as Saurashtra, Kutch, Narmada-Tapti tectonic zone (NTTZ) of Central India, South Rewa basin and Son-Mahanadi basin and their estimated densities are 2.73 g/cm³, 2.57 g/cm³, 2.58 g/cm³, 2.55 g/cm³, and 2.60 g/cm³, which are different from the standard density of 2.67 g/cm³ typically used for average crustal density. The Saurashtra peninsula, overlain by Deccan volcanics, shows a higher slab density (2.73 g/cm³), and the Bouguer anomaly map reveals the presence of a broad gravity low superimposed on the regional topography, which suggests isostatic compensation of the excess topographic load. Fractal analysis of free-air anomalies (FA) and topography data shows that FA is mainly influenced by topography at shorter wavelengths and by isostasy at longer wavelengths. Gravity modeling of isostatic regional anomalies incorporating constraints from seismic studies revealed the presence of thickened underplated high-density mafic crust beneath the Saurashtra peninsula. Thus, the innovative aspect lies in the use of fractal analysis to understand the relationship between isostasy and topography.

在区域地球动力学研究中，布格异常总是使用2.67 g/cm3的板密度计算。然而，分形方法可以用来估计布格板的实际密度。本文应用分形方法对印度半岛索拉什特拉、库奇、纳尔玛达-塔普提构造带（NTTZ）、南雷瓦盆地和Son-Mahanadi盆地等构造区布格板密度进行了计算，其密度分别为2.73 g/cm3、2.57 g/cm3、2.58 g/cm3、2.55 g/cm3和2.60 g/cm3，不同于一般平均地壳密度的标准密度2.67 g/cm3。Saurashtra半岛被德干火山覆盖，显示出较高的板块密度（2.73 g/cm3），布格异常图显示在区域地形上存在广泛的重力低叠加，这表明过量的地形负荷得到了均衡补偿。自由空气异常（FA）和地形数据的分形分析表明，FA主要受较短波长的地形和较长波长的均衡的影响。结合地震研究约束的均衡区域异常重力模拟显示，在索拉什特拉半岛下存在增厚的下镀高密度基性地壳。因此，创新之处在于使用分形分析来理解均衡与地形之间的关系。

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引用次数: 0

Grain size evolution in mantle convection models promotes continuous rather than episodic tectonics 地幔对流模式的粒度演化促进了连续构造而不是幕式构造

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2025-12-16 DOI: 10.1016/j.pepi.2025.107488

Antonio Manjón-Cabeza Córdoba , Tobias Rolf , Maëlis Arnould

A long-persistent caveat of geodynamic models with Earth-like tectonic behavior is the need of an ad hoc yield stress lower than any laboratory-inferred rock strength. The actual physical processes that govern the strength of the lithosphere are still debated. Grain size reduction due to dynamic recrystallization promotes local weak zones in the lithosphere thereby facilitating lithospheric breakdown and continuous mobile-lid tectonics. Grain growth should instead (re-)strengthen the lithosphere and inhibit this regime. By modeling mantle convection in a spherical annulus, we analyze the impact of grain size evolution (GSE) on the global tectonic style. GSE, together with composite rheology, modifies the diagnostics within one tectonic regime. Indeed, considering grain growth enables high viscosity in the lower mantle, with broad stable plumes. Grain reduction, on the other hand, increases the number of subduction zones, also making them shorter-lived. We find that grain size reduction suppresses episodic behavior and facilitates surface mobility over a range of lithospheric yield stresses, but GSE has no discernible effect on the transition to stagnant-lid tectonics. Moreover, increased grain growth does not result in higher episodicity either. These findings support the relevance of grain size evolution for stabilizing mobile-lid tectonics vs episodic tectonics, and may explain lower mantle features and reconcile geophysical observations; but they also cast doubt on the potential of damage to explain mobile-lid tectonics up to laboratory-inferred strengths.

对于具有类似地球构造行为的地球动力学模型，一个长期存在的警告是，需要一个比任何实验室推断的岩石强度都要低的特别屈服应力。控制岩石圈强度的实际物理过程仍在争论中。动态再结晶导致的颗粒尺寸减小促进了岩石圈局部弱带的形成，从而促进了岩石圈的破裂和持续的活动盖构造。相反，颗粒生长应该（重新）加强岩石圈并抑制这一机制。通过模拟球形环空的地幔对流，分析了地幔颗粒粒度演化对全球构造样式的影响。GSE与复合流变学一起，修改了在一个构造状态下的诊断。事实上，考虑到颗粒的生长可以使下地幔具有高粘度，具有广泛的稳定羽流。另一方面，颗粒减少增加了俯冲带的数量，也使它们的寿命缩短。我们发现，在岩石圈屈服应力范围内，晶粒尺寸减小抑制了幕式行为并促进了地表迁移，但GSE对向滞盖构造过渡没有明显的影响。此外，谷物生长的增加也不会导致更高的偶发性。这些发现支持了颗粒大小演化与稳定活动盖构造和幕式构造的相关性，并可能解释下地幔特征和调和地球物理观测；但他们也对破坏的可能性提出了质疑，无法解释实验室推断出的移动盖构造强度。

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引用次数: 0

Boundary layer interactions in mantle convection: Peaks, limits and effects on convective scaling relations 地幔对流中的边界层相互作用：对对流标度关系的峰值、极限和影响

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2025-12-12 DOI: 10.1016/j.pepi.2025.107485

Julian Garrido-Tomasini , Adrian Lenardic , William Moore

Convection in the Earth’s mantle is associated with two thermal boundary layers: the Earth’s thermal lithosphere and a layer above the core-mantle boundary, generally considered the source of plumes. Classical convection theory, often applied to thermal-tectonic history modeling, assumes that convective boundary layers do not interact and their dynamics are self-determined. However, present-day observations of plumes reaching the lithosphere and slabs sinking to the core–mantle boundary indicate that boundary layer interactions are a component of mantle dynamics. Whether this was the case over Earth’s history motivates the 3D thermal convection simulations herein. We investigate boundary layer interactions to determine: (1) The level of convective vigor, measured by the Rayleigh number, at which interactions peak; (2) The level at which interactions cease; (3) Whether interactions are responsible for deviations in convective scalings from classical theory predictions. We found that interactions peak near a Rayleigh number of

1 0^{7}

. Beyond that, they decrease, but changes in convective planform led to local peaks. Classical scaling theory for heat flux and velocity is not recovered until Rayleigh numbers exceed

3 \times 1 0^{9}

, after which the convective planform remains in a chaotic plume regime and interactions continually decrease. We attribute deviations from classic theory to these interactions altering boundary layer structure from what would be observed if their dynamics were self-determined. We demonstrate that the deviations are not solely due to thermal effects, but also mechanical effects. We found that interactions are at a peak near present-day mantle conditions. We discuss implications for geodynamics and mantle evolution.

地幔中的对流与两个热边界层有关：地球的热岩石圈和核心-地幔边界之上的一层，通常被认为是羽流的来源。经典对流理论通常应用于热构造史建模，它假设对流边界层不相互作用，其动力学是自定的。然而，目前对到达岩石圈的地幔柱和下沉到岩心-地幔边界的板块的观测表明，边界层相互作用是地幔动力学的一个组成部分。地球历史上是否存在这种情况激发了本文的三维热对流模拟。我们通过研究边界层相互作用来确定：(1)通过瑞利数测量的对流活力水平，在相互作用达到峰值时；(2)相互作用停止的水平；(3)相互作用是否导致对流标度偏离经典理论预测。我们发现相互作用在瑞利数107附近达到峰值。除此之外，它们会减少，但对流平台的变化导致局部峰值。经典的热通量和速度标度理论直到瑞利数超过3×109才恢复，此后对流平台仍处于混沌羽流状态，相互作用不断减弱。我们将经典理论的偏差归因于这些相互作用改变了边界层结构，如果它们的动力学是自定的，将会观察到什么。我们证明了这些偏差不仅是由于热效应，而且是由于机械效应。我们发现，在现今的地幔条件下，相互作用达到了顶峰。我们讨论了地球动力学和地幔演化的意义。

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引用次数: 0

Improving the reconstruction of Holocene geomagnetic paleosecular variation in the Antarctic region 改进南极地区全新世地磁古长期变化的重建

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2025-12-11 DOI: 10.1016/j.pepi.2025.107487

Leonardo Sagnotti , Chiara Caricchi , Patrizia Macrì , Ester Colizza , Paola Del Carlo , Alessio Di Roberto , Aldo Winkler

We present new paleomagnetic data from the ANTA02-AV43 core collected in the Ross Sea (Antarctica), spanning the last 10 ka. Results document a relative paleointensity (RPI) record that closely matches predictions from global geomagnetic models and from previously published records from nearby peri-Antarctic margins, including the Ross Sea and Wilkes Land Basin, covering the same time interval. The stratigraphic trends of directional paleomagnetic data from this study show features that are also consistent with global model predictions and earlier published data, supporting regional reconstructions of geomagnetic paleosecular variation (PSV). Notable differences reflect effects such as sedimentary inclination shallowing and the arbitrary restoration of magnetic declination in marine cores lacking azimuthal orientation.

We combined the new ANTA02-AV43 dataset with existing Holocene records from two additional sediment cores of comparable resolution to develop the paleomagnetic “HOLOANTA” stack. This composite record averages paleomagnetic data over the last 10,000 years in 200-year intervals. It includes RPI as well as paleomagnetic inclination and declination data, providing a robust regional Holocene RPI curve alongside directional secular variation (PSV) trends. The HOLOANTA stack serves as a novel tool to support high-resolution correlation between sedimentary cores and the development of detailed age models in marine sequences from the peri-Antarctic margins.

本文介绍了南极罗斯海ANTA02-AV43岩心近10 ka的新古地磁资料。研究结果表明，相对古强度（RPI）记录与全球地磁模型的预测和之前发表的南极周边边缘（包括罗斯海和威尔克斯陆盆）的记录非常吻合，这些记录覆盖了相同的时间间隔。本研究的定向古地磁资料的地层趋势也显示出与全球模式预测和早期发表的资料一致的特征，支持了地磁古长期变化（PSV）的区域重建。这些显著差异反映了沉积倾角变浅和缺乏方位定位的海相岩心磁偏角的任意恢复等影响。我们将新的ANTA02-AV43数据集与另外两个具有相当分辨率的沉积物岩心的全新世记录相结合，建立了古地磁“HOLOANTA”叠。这一合成记录以200年的间隔平均了过去1万年的古地磁数据。它包括RPI以及古地磁倾角和赤纬数据，提供了一个强大的区域全新世RPI曲线以及定向长期变化（PSV）趋势。HOLOANTA叠层作为一种新的工具，可以支持沉积岩心之间的高分辨率相关性，并开发出南极边缘海相序列的详细年龄模型。

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引用次数: 0

Lithospheric deformation across Dhubri-Chungthang Fault Zone: New insights into Himalayan segmentation 杜布里-忠塘断裂带岩石圈变形：喜马拉雅分割的新认识

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2025-12-06 DOI: 10.1016/j.pepi.2025.107486

Aamir Salam Siddiqui , Arun Singh , Chandrani Singh , Debasis D. Mohanty , Gaurav Kumar , Niptika Jana

We trace signatures of lithospheric deformation beneath Sikkim Himalaya using newly acquired data of core-mantle refracted shear wave phases (SKS/SKKS) from 27 broadband seismic stations covering the region. Here, the underthrusting India plate is possibly segmented by the Dhubri-Chungthang Fault Zone (DCFZ), a major fault zone passing through Sikkim. While the presence of the DCFZ is more or less substantiated by seismicity, its structural imprints in the deep lithosphere remain elusive. Shear wave splitting (SWS) parameters (fast polarization direction

ϕ

and delay time

δ t

) from SKS/SKKS phases analyse the extent and pattern of deformation beneath Sikkim Himalaya. Robust individual and mean SWS measurements show a particular trend of variational deformation patterns throughout Sikkim, with a significant transition in

δ

t (0.3–2.5 s) and

ϕ

across the DCFZ. The variation in deformation pattern across the DCFZ, represent the influence of the DCFZ on the deep lithospheric scale segmentation of the Indian plate. The dominant E-W (

\sim

100°) pattern in

ϕ

with smaller

δ

t values (

\sim

0.3 s) in southern Sikkim within the Main Central Thrust region represents the dominance of compressional tectonics with a possible multi-layer anisotropy scenario. While the spatially dispersed seismic stations in the Himalayan foreland are dominated by deformation pattern parallel to the Absolute Plate Motion of the Indian plate,

ϕ

patterns are governed by the shear caused by the basal drag at the base of the Indian lithosphere. While a NE pattern of

ϕ

is dominant here, some deviations may be due to different driving forces related to the Indian plate position.

利用覆盖该地区27个宽带地震台站新获得的核幔折射横波相位（SKS/SKKS）数据，对锡金喜马拉雅地区岩石圈变形特征进行了追踪。在这里，逆冲下的印度板块可能被穿过锡金的主要断裂带杜布里-忠塘断裂带（DCFZ）分割。虽然地震活动或多或少地证实了DCFZ的存在，但它在岩石圈深处的结构印记仍然难以捉摸。来自SKS/SKKS相位的剪切波分裂（SWS）参数（快速极化方向φ和延迟时间δt）分析了锡金喜马拉雅地区的变形范围和模式。稳健的个体和平均SWS测量结果显示，整个锡金地区的形变模式有特殊的变化趋势，δt （0.3-2.5 s）和φ在DCFZ上有显著的转变。整个DCFZ的形变模式变化，反映了DCFZ对印度板块深部岩石圈尺度分割的影响。在锡金南部，在主中央逆冲区内，主导的ϕ与较小的δt值（~ 0.3 s）较小的E-W（~ 100°）模式代表了挤压构造的主导地位，可能是多层各向异性的情景。喜马拉雅前陆的空间分散地震台站主要受平行于印度板块绝对板块运动的形变模式支配，而其中的φ模式主要受印度岩石圈底部基底阻力引起的剪切模式支配。虽然这里的NE型ϕ占主导地位，但一些偏差可能是由于与印度板块位置相关的不同驱动力。

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引用次数: 0

Effects of rheological parameters on the stability of thermochemical piles: A comparison of different origins 流变参数对热化学桩稳定性的影响：不同来源的比较

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2025-12-03 DOI: 10.1016/j.pepi.2025.107476

Henry W. Sitte, Claudia Stein, Carolin Weber, Ulrich Hansen

Large low shear velocity provinces have been observed beneath Africa and the Pacific. These large-scale structures are considered to have been stable the last hundred million years with their origin and nature still being an open question.

In our 2D Cartesian study, we numerically investigate the temporal and spatial stability of thermochemical piles. We consider two different scenarios, in which the piles either arise from a primordial layer above the core-mantle boundary (CMB) or from an influx of iron-rich material through the CMB. The investigated mantle flow depends on viscosity varying with composition, depth, and stress. The rheological parameters affect the strength of convection and consequently the stability of piles. An increased top or bottom viscosity reduces the convective vigor yielding longer-lived and more stable piles. Likewise, a thermal expansivity decreasing with depth exhibits longer pile lifetimes and less pile movement. Furthermore, piles and plumes are two closely linked structures. While thermochemical plumes are anchored by piles, thermal plumes attract piles and deform them. Long-lived plumes tend to be located in the center of piles, but during dynamical processes, such as merging of piles, plumes also occur at the edges remaining there for several million years.

In summary, we suggest that the LLSVPs might have formed early after the magma ocean, probably as several initially thin structures due to strong convection in the hot Archean mantle. With the cooling of the mantle, the structures would have broadened and stabilized in space and time, yielding the present-day state.

在非洲和太平洋下面观测到大的低切变速度省。这些大型结构被认为在过去的一亿年里是稳定的，它们的起源和性质仍然是一个悬而未决的问题。在我们的二维笛卡尔研究中，我们数值研究了热化学桩的时空稳定性。我们考虑了两种不同的情况，在这种情况下，堆要么来自核幔边界（CMB）上方的原始层，要么来自通过CMB涌入的富铁物质。所研究的地幔流动取决于粘度随成分、深度和应力的变化。流变参数影响桩的对流强度，从而影响桩的稳定性。增加的顶部或底部粘度降低了对流活力，使桩的寿命更长，更稳定。同样，热膨胀系数随深度减小，桩的寿命更长，桩的运动更少。此外，桩和柱是两个紧密相连的结构。当热化学羽流被桩锚定时，热羽流吸引桩并使其变形。长寿命的羽流往往位于桩的中心，但在动力过程中，如桩的合并，羽流也会出现在边缘，并在那里停留数百万年。综上所述，我们认为llsvp的形成可能早于岩浆海，可能是由于太古宙热地幔的强对流而形成的几个最初的薄结构。随着地幔的冷却，这些结构会在空间和时间上变宽并稳定下来，从而形成今天的状态。

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引用次数: 0

Non-negligible oxygen in the inner core: Investigating the partitioning between liquid and HCP iron 内核中不可忽略的氧：研究液体和HCP铁之间的分配

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2025-11-28 DOI: 10.1016/j.pepi.2025.107477

Qianxi Chen , Hua Yang , Feiwu Zhang , Joshua M.R. Muir

Oxygen is a light element that is likely present in the Earth's outer core, yet its solubility in the inner core has conventionally been regarded as negligible, based on previously measured or calculated low partition coefficients from liquid to solid iron. By employing ab initio molecular dynamics simulations under core conditions, we show that a superionic transition allows oxygen to incorporate into solid HCP‑iron at concentrations of 0.3–0.37 wt%, exceeding the < 0.1 wt% limit of substitutional models. Moreover, the softening effect of superionic oxygen on HCP-iron is more pronounced than that induced by substitutional oxygen. These results challenge the traditional paradigm of oxygen exclusion in the inner core and emphasize the importance of incorporating superionic transport into future models of core composition.

氧是一种很可能存在于地球外核的轻元素，但它在地心的溶解度通常被认为是可以忽略不计的，这是基于以前测量或计算的从液态到固态铁的低分配系数。通过在核心条件下进行从头算分子动力学模拟，我们发现超离子跃迁允许氧以0.3-0.37 wt%的浓度并入固体HCP -铁中，超过了替代模型的0.1 wt%的限制。此外，超离子氧对hcp -铁的软化作用比取代氧更明显。这些结果挑战了传统的内核氧排斥范式，并强调了将超电子输运纳入未来核心组成模型的重要性。

引用次数: 0

Water in the lower mantle: constraints from mineral physics and phase equilibrium data 下地幔中的水：来自矿物物理和相平衡数据的约束

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2025-11-12 DOI: 10.1016/j.pepi.2025.107475

Li Zhang , Qun-ke Xia

Water cycle in the Earth’s deep interior plays a critical role in mantle dynamics. Some subducting materials can reach the core-mantle boundary delivering water along the subduction path. High water content in basalts of ocean islands and large igneous provinces, which were formed by mantle plumes, suggests the presence of water-rich sources in the lower mantle. The seismic observation of low-velocity anomalies in the uppermost lower mantle may imply partial melting associated with water transport out of the transition zone and the released hydrous melts can migrate into the overlying crust layer. Recent experiments indicate that hydrated aluminous silica phases are the best candidate hosts for water transport in slab crust in the lower mantle down to the core mantle boundary owing to their high water storage capacity and exceptional thermal stability. The presence of H₂O significantly lowers the stishovite-to-poststishovite transition pressure to a much shallower depth <1000 km and further stabilizes alumina-rich NiAs-type silica phase (Nt) at the depth >1800 km. In peridotitic compositions, the δ-H solid solution AlOOH–MgSiO₄H₂ is a potential water carrier. The alumina and water partitioning under the lower mantle conditions significantly changes the transition thickness of bridgmanite-to-postperovskite, which allows reasonable interpretation of the seismic scatters and discontinuity in the lower mantle. At the core-mantle boundary, water released upon heating may induce partial melting in subducted oceanic crust, possibly accounting for the ultra-low-velocity zones (ULVZs) detected in high-velocity region. Future studies on multicomponent systems under high pressure and high temperature conditions will be needed to understand how water is exchanged between various mantle reservoirs and how the subducted water and dehydration melting affects the dynamics at the core-mantle boundary.

地球深处的水循环在地幔动力学中起着至关重要的作用。一些俯冲物质可以到达核幔边界，沿着俯冲路径输送水。地幔柱形成的洋岛玄武岩和大火成岩省玄武岩含水量高，表明下地幔存在富水源。下上地幔低速异常的地震观测可能暗示了部分熔融与水从过渡带运出有关，释放的含水熔体可能迁移到上覆地壳层。最近的实验表明，水合硅铝相具有较高的储水能力和优异的热稳定性，是下地幔板块地壳向地核地幔边界输水的最佳候选寄主。H2O的存在显著降低了较浅深度（1000 km）的石橄榄岩-后石橄榄岩转变压力，并进一步稳定了深度（1800 km）的富铝nias型二氧化硅相（Nt）。在橄榄岩组分中，δ-H固溶体aloh - mgsio4h2是潜在的水载体。下地幔条件下氧化铝和水的配分显著改变了桥锰矿-后钙钛矿的过渡厚度，合理解释了下地幔的地震散射和不连续。在核幔边界，加热释放的水可能引起俯冲洋壳的部分熔融，这可能是在高速区探测到超低速带的原因。未来需要对高压高温条件下的多组分系统进行研究，以了解不同地幔储层之间的水交换以及俯冲水和脱水熔融如何影响核幔边界的动力学。

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引用次数: 0