Physics of the Earth and Planetary Interiors最新文献

An effective 3D inversion algorithm of CSEM and its application in geothermal exploration 一种有效的CSEM三维反演算法及其在地热勘探中的应用

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2026-02-01 DOI: 10.1016/j.pepi.2026.107501

Ningbo Bai , Zhiqiang Chen , Bo Han , Junjun Zhou , Wenlong Zhou , Guoshu Huang , Xiangyun Hu

Electromagnetic methods play a critical role in geothermal exploration due to their strong sensitivity to key system components, including heat sources, reservoirs, and caprocks. However, practical three-dimensional controlled-source electromagnetic (CSEM) inversion for geothermal targets remains computationally challenging because of the extremely high model dimensionality and the prohibitive cost of repeatedly solving large-scale linear systems within Gauss–Newton (GN) frameworks. These limitations restrict the application of high-resolution 3D CSEM inversion to real geothermal field data. To address this unresolved problem, we propose an efficient 3D CSEM Gauss–Newton inversion algorithm based on solution space dimension reduction (SSDR). The core novelty of the proposed approach lies in the integration of SSDR with a direct–iterative hybrid solver (DIHS), which reduces the effective degrees of freedom in the inversion model while preserving the accuracy required for forward and adjoint electromagnetic simulations. This strategy significantly improves computational efficiency without sacrificing inversion fidelity, thereby advancing the feasibility of high-resolution 3D CSEM inversion in complex geothermal settings. The accuracy, stability, and efficiency of the proposed algorithm are systematically validated through numerical experiments on layered and geothermal models. Furthermore, the method is applied to the three-dimensional inversion of field-based CSEM data from the Yingshan geothermal area, Hubei Province, China, demonstrating high reliability and practical effectiveness. By jointly interpreting inversion results from both magnetotelluric (MT) and CSEM datasets, the geothermal genesis pattern of the study area is analyzed and a conceptual geothermal genetic model is established. These results provide important technical support for geothermal resource exploration and development, and illustrate how the proposed method advances the state of the art in 3D electromagnetic inversion for geothermal applications.

电磁法由于对热源、储层和盖层等关键系统的敏感性强，在地热勘探中起着至关重要的作用。然而，由于极高的模型维数和在高斯-牛顿（GN）框架内反复求解大规模线性系统的高昂成本，地热目标的实际三维可控源电磁（CSEM）反演在计算上仍然具有挑战性。这些局限性限制了高分辨率三维CSEM反演在实际地热田数据中的应用。为了解决这一尚未解决的问题，我们提出了一种基于解空间降维（SSDR）的高效三维CSEM高斯-牛顿反演算法。该方法的核心新颖之处在于将SSDR与直接迭代混合求解器（DIHS）相结合，降低了反演模型的有效自由度，同时保持了正演和伴随电磁模拟所需的精度。该策略在不牺牲反演保真度的前提下显著提高了计算效率，从而提高了复杂地热环境下高分辨率三维CSEM反演的可行性。通过层状模型和地热模型的数值实验，系统地验证了算法的准确性、稳定性和高效性。并将该方法应用于湖北鹰山地热区的地温三维反演，结果表明该方法具有较高的可靠性和实用性。通过对大地电磁法（MT）和断层电磁法（CSEM）反演结果的联合解释，分析了研究区地热成因模式，建立了地热成因概念模型。这些结果为地热资源勘探和开发提供了重要的技术支持，并说明了该方法在地热应用的三维电磁反演方面的最新进展。

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引用次数: 0

Magnetic reversals in a geodynamo model with a stably–stratified layer 具有稳定分层层的地球动力学模型中的磁倒转

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2026-02-01 DOI: 10.1016/j.pepi.2026.107502

Nicolás P. Müller , Christophe Gissinger , François Pétrélis

We study the process of magnetic reversals in the presence of a stably-stratified layer below the core-mantle boundary using direct numerical simulations of the incompressible magnetohydrodynamics equations under the Boussinesq approximation in a spherical shell. We show that the dipolar-multipolar transition shifts to larger Rayleigh numbers in the presence of a stably-stratified layer, and that the dipolar strength of the magnetic field at the core-mantle boundary increases due to the skin effect. By imposing an heterogeneous heat flux at the outer boundary, we break the equatorial symmetry of the flow, and show that different heat flux patterns can trigger different dynamo solutions, such as hemispheric dynamos and polarity reversals. Using kinematic dynamo simulations, we show that the stably-stratified layer leads to similar growth rates of the dipole and quadrupole components of the magnetic field, playing the role of a conducting boundary layer, favouring magnetic reversals, and a dynamics predicted by low-dimensional models.

本文利用球壳中Boussinesq近似下不可压缩磁流体动力学方程的直接数值模拟，研究了在核幔边界下存在稳定分层层时的磁反转过程。我们发现，偶极-多极跃迁在稳定分层层存在时转向更大的瑞利数，并且由于趋肤效应，地核-地幔边界的磁场偶极强度增加。通过在外边界施加非均匀热通量，我们打破了气流的赤道对称，并表明不同的热通量模式可以触发不同的发电机解，如半球发电机和极性反转。利用运动学发电机模拟，我们发现稳定分层的层导致磁场偶极子和四极子分量的相似增长率，发挥导电边界层的作用，有利于磁反转，以及低维模型预测的动力学。

引用次数: 0

Modelling earth's magnetic field over southern Africa between 2014 and 2023 applying revised spherical cap harmonic analysis (R-SCHA) on Swarm satellite and ground-based data 基于Swarm卫星和地面数据，应用修正球帽谐波分析（R-SCHA）模拟2014 - 2023年非洲南部地球磁场

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2026-01-28 DOI: 10.1016/j.pepi.2026.107504

S.L. Khanyile , E. Nahayo , F.J. Pavon-Carrasco , M. Puente-Borque

The Southern African region is in the eastern part of the South Atlantic Anomaly. The Earth's magnetic field variation in this region is characterized by high spatial and temporal magnetic field gradients. The study of fast core field variations requires an accurate regional geomagnetic field model that can capture temporal and spatial small-scale features of the geomagnetic field variation, which are sometimes missed by the global field models. A regional model of the Earth's magnetic field and its secular variation was developed over the Southern African region using the technique of the Revised Spherical Cap Harmonic Analysis (R-SCHA) applied on data from the Swarm satellite and ground-based magnetic measurements between 2014 and 2023. Its accuracy was validated against the global CHAOS-8.1 model and the ground-based data from four magnetic observatories in the region, Hermanus (HER), Hartebeesthoek (HBK), Tsumeb (TSU), and Keetmanshoop (KMH). The Root Mean Square Error (RMSE) for X, Y, and Z field components between the model input Swarm data and predictions from the R-SCHA model were 2.7 nT, 2.1 nT, and 1.4 nT, and from the CHAOS-8.1 model were 2.7 nT, 2.2 nT, and 1.9 nT, respectively. For ground observatory data (after removing the crustal biases), the R-SCHA model yielded RMSE values of 2.9 nT, 2.3 nT, and 1.9 nT compared to 3.8 nT, 2.9 nT, and 2.8 nT from the CHAOS-8.1 model. The R-SCHA regional model captured secular variation features consistent with ground observatory data, revealing geomagnetic jerk in 2019–2020 and a distinct V-shaped jerk in 2021 across all observatories in the X and Z components, findings that are confirmed by the CHAOS-8.1 model. The results show rapid secular variation fluctuations in the X component in 2018 at HER and TSU observatories, and an abrupt change in the linear secular variation trend around 2022–2023 at all observatories, which is clearly visible in the X and Z components. The average rate of change of the total field strength between 2018.5 and 2023.5 epochs decreases, reaching 80 nT/year in the western part of the region, while in the eastern areas it slightly increases, reaching 40 nT/year.

南部非洲地区位于南大西洋异常区的东部。该地区地磁场变化具有较高的时空梯度特征。研究地核磁场的快速变化需要精确的区域磁场模型，该模型能够捕捉地磁变化的时空小尺度特征，而全球磁场模型有时会忽略这些特征。利用修正球帽谐波分析（R-SCHA）技术，对2014年至2023年Swarm卫星和地面磁场测量数据进行分析，在南部非洲地区建立了地球磁场及其长期变化的区域模型。利用全球CHAOS-8.1模型和该地区Hermanus （HER）、Hartebeesthoek （HBK）、Tsumeb （TSU）和keetmanshop （KMH）四个地磁观测站的地面数据验证了其准确性。模型输入Swarm数据与R-SCHA模型预测的X、Y和Z场分量的均方根误差（RMSE）分别为2.7 nT、2.1 nT和1.4 nT, chaoos -8.1模型的均方根误差分别为2.7 nT、2.2 nT和1.9 nT。对于地面观测数据（去除地壳偏差后），R-SCHA模型的RMSE值分别为2.9 nT、2.3 nT和1.9 nT，而CHAOS-8.1模型的RMSE值分别为3.8 nT、2.9 nT和2.8 nT。R-SCHA区域模型捕获了与地面观测站数据一致的长期变化特征，揭示了2019-2020年所有观测站在X和Z分量上的地磁跳变和2021年明显的v形跳变，这些发现得到了CHAOS-8.1模型的证实。结果表明，2018年HER和TSU台站X分量的长期变化波动较快，所有台站在2022-2023年前后的长期线性变化趋势都发生了突变，这在X和Z分量中表现得非常明显。总场强在2018.5 ~ 2023.5期的平均变化率减小，西部地区达到80 nT/年，东部地区略有增加，达到40 nT/年。

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引用次数: 0

Electromagnetic signatures of the tectono-magmatic processes in eastern Ladakh and their implications for geothermal energy potential of the region

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2026-01-20 DOI: 10.1016/j.pepi.2026.107503

G. Pavankumar, A. Manglik, N.N. Chakravarthi, M. Demudu Babu, Raj Sunil Kandregula

The Ladakh region preserves the imprints of the subduction – collision process between the Indian and the Eurasian plates and also has geothermal energy potential. However, geophysical information crucial for understanding the regional tectono-magmatic processes and identification of sustainable potential geothermal reservoirs is still scanty, especially for eastern Ladakh. We have carried out a magnetotelluric study in eastern Ladakh along a transect traversing from the Tso Morari to the Pangong Tso. The crustal geoelectric structure delineated by 2-D and 3-D inversions reveals several significant features. These include: (i) transition of resistive Indian plate crust to moderately resistive crust across the Indus Suture Zone, (ii) base of the Ladakh batholith at 18–20 km depth, (iii) a prominent conductivity anomaly at 15–35 km depth beneath the Shyok Suture Zone, (iv) connectivity of the Puga, Chumathang and Gaik hotsprings to a single conductor at about 5 km depth, and (v) presence of another conductor in 5–15 km depth at Tso Morari. We infer a multi-level system of conductors in which the deepest one at 40 km depth in western Tibet feeds the conductors along the Karakoram fault and beneath the Ladakh batholith, which in turn feed the conductors beneath the Puga-Chumathang and Tso Morari. These results imply a much larger geothermal energy potential for the Ladakh region compared to the prevailing estimates. A change in the geoelectric strike from NW-SE between Tso Morari and Chushul to E-W further north implies dominant influence of E-W tectonics of the western Tibet at the northern sites.

二维和三维反演所描绘的地壳地电结构揭示了几个重要特征。左莫拉里和楚舒尔之间的地电走向由北西-东西向北至西西向北的变化表明，藏西的东西向构造对北部遗址的影响占主导地位。

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引用次数: 0

Ladakh batholith emplacement mechanism based on analysis of magnetic fabric and mineralogy

IF 1.9 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Physics of the Earth and Planetary Interiors

Pub Date : 2026-01-06 DOI: 10.1016/j.pepi.2026.107500

A.V. Satyakumar , M. Venkateshwarlu

We report the outcomes of the anisotropy of magnetic susceptibility (AMS), rock magnetic properties, and microscopic observations of the Ladakh Batholith (LB). Our magnetic mineralogy reveals that Ti-magnetite pseudo-single domain is the main magnetic mineral, with other minerals including quartz, biotite, and feldspar. AMS study reveals that the magnetic fabric is reliable for ∼NW-SE trending magma flow. Notably, we see established magnetic lineation and foliation, as well as major susceptibility axes that are well-grouped and exhibit a triaxial distribution regardless of their shape factor (T). Magma flow direction is inferred from the magnetic fabric orientation, i.e., the direction of maximal susceptibility, K₁. Concentric magnetic lineations and foliations appear to follow the boundaries of plutons and mostly represent the movements of magma chambers. This study reveals that the LB may have grown due to multi-stage interactions between host Ladakh granitoids and several pulses of coeval mafic and felsic magmas.

磁性矿物学研究表明，磁性矿物主要为钛磁铁矿伪单畴，其他矿物包括石英、黑云母、长石等。AMS研究表明，磁结构对~ NW-SE向岩浆流动是可靠的。值得注意的是，我们看到了已建立的磁性线理和片理，以及主要的磁化率轴，无论其形状因子(T)如何，它们都很好地分组并呈现三轴分布。岩浆流动方向由磁组构方向推断，即最大磁化率方向K1。同心磁线和片理沿岩体边界出现，主要代表岩浆房的运动。

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