Earth and Planetary Science Letters最新文献_第7页

Shifting carbonate burial between oceanic and continental crust across Earth history 在整个地球历史中，在海洋和大陆地壳之间转移碳酸盐埋藏

IF 4.8 1区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Earth and Planetary Science Letters

Pub Date : 2026-01-05 DOI: 10.1016/j.epsl.2025.119810

Jon M. Husson , Shanan E. Peters

Chemical weathering fluxes determine carbonate burial rates on geologic timescales, but the locus of carbonate burial is sensitive to tectonic and biologic boundary conditions that have changed across Earth history. Depositional setting is important because sediments on oceanic crust are readily recycled on the timescale of seafloor subduction, whereas sediments on continental crust can be sequestered over much longer durations. Here we present records of carbonate abundance in continental sediments for the past 3600 million years based on the North American components of the Macrostrat geologic column database and globally-distributed geological map units. Whether carbonate abundance is measured in absolute (area, volume) or in relative terms (carbonate normalized by total sediment), secular patterns emerge. In the Precambrian, carbonate abundance in continental crust is generally low. In the Phanerozoic, it climbs abruptly to a Paleozoic maximum and then declines towards the present. Decrease in shelf carbonate abundance across the Phanerozoic has been previously documented, driven in part by evolving paleogeography and the early Mesozoic evolution of pelagic calcifiers, which helped to shift carbonate burial from continental to oceanic crust. A Precambrian low in continental carbonate has received less attention. Here we propose that carbonate burial during much of the Precambrian was dominated by accumulation on (or within) oceanic crust and then shifted to continental crust in the early Paleozoic. Carbonate burial fluxes calibrated from the surviving rock record are an order of magnitude larger in the early Paleozoic than they appear to have been in the Proterozoic, with a step-wise increase occurring during the Ediacaran-Cambrian transition. This observation implies a large and relatively abrupt shift in the principal locus of CaCO₃ burial, from short-lived oceanic crust during much of the Proterozoic to longer-surviving continental crust in the early Paleozoic. Oceanic crust became, once again, a significant locus for carbonate accumulation during the Mesozoic and Cenozoic. The Paleozoic accommodation of most of the global carbon burial flux on the continents has many implications, including for secular changes in carbon cycling rates and the sensitivity of the surface environment to CO₂ injections.

化学风化通量决定了地质时间尺度上的碳酸盐埋藏速率，但碳酸盐埋藏的位置对地球历史上不断变化的构造和生物边界条件很敏感。沉积环境很重要，因为海洋地壳上的沉积物在海底俯冲的时间尺度上很容易再循环，而大陆地壳上的沉积物可以在更长的时间内被隔离。本文基于macrostrata地质柱数据库的北美成分和全球分布的地质图单元，给出了过去36亿年大陆沉积物中碳酸盐丰度的记录。无论碳酸盐丰度是以绝对（面积、体积）还是以相对（碳酸盐按总沉积物归一化）来衡量，都会出现长期模式。在前寒武纪，大陆地壳碳酸盐丰度普遍较低。在显生宙，它突然攀升到古生代的最大值，然后向现在下降。在显生宙，陆架碳酸盐丰度的减少已经有文献记载，部分原因是古地理的进化和中生代早期上层钙化物的进化，这有助于将碳酸盐埋藏从大陆地壳转移到海洋地壳。陆相碳酸盐岩的前寒武纪低沉积受到的关注较少。本文认为，在前寒武纪的大部分时间里，碳酸盐岩的埋藏主要是在海洋地壳上（或在海洋地壳内）聚集，然后在早古生代转移到大陆地壳。根据现存岩石记录校准的碳酸盐埋藏通量在早古生代比在元古代要大一个数量级，在埃迪卡拉纪-寒武纪过渡期间，碳酸盐埋藏通量逐步增加。这一观察结果表明，CaCO3埋藏的主要地点发生了一次较大且相对突然的转变，从元古代大部分时间的短暂海洋地壳到古生代早期存活时间较长的大陆地壳。在中生代和新生代，洋壳再次成为碳酸盐岩聚集的重要场所。古生代对大陆上大部分全球碳埋藏通量的调节具有许多意义，包括碳循环速率的长期变化和地表环境对二氧化碳注入的敏感性。

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引用次数: 0

IF 4.8 1区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Earth and Planetary Science Letters

Pub Date : 2026-01-01

引用次数: 0

IF 4.8 1区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Earth and Planetary Science Letters

Pub Date : 2026-01-01

引用次数: 0

IF 4.8 1区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Earth and Planetary Science Letters

Pub Date : 2026-01-01

引用次数: 0

Coupled trace element and Hf-isotope measurements of Hadean through Paleoarchean zircons from the Singhbhum Craton indicate derivation from a long-lived, mantle-derived protocrust singhbham克拉通古宙至古太古代锆石的微量元素和hf同位素耦合测量表明，它起源于一个长寿命的幔源原地壳

IF 4.8 1区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Earth and Planetary Science Letters

Pub Date : 2025-12-31 DOI: 10.1016/j.epsl.2025.119813

Heather Kirkpatrick , Emily Stoll , Nadja Drabon

Due to the dearth of rock records during the Hadean, little is known about early crustal chemistry and geodynamics. Here, we present zircon trace and rare earth element and Lu-Hf measurements of zircons ∼ 3.3 Ga to ∼ 4.2 Ga from the Older Metamorphic Tonalitic Gneiss in the Singhbhum Craton to better understand geodynamic changes during the Hadean and Archean. We find decreasing, subchondritic zircon ε_HfT among zircons > 3.7 Ga and no indication of addition of new crustal material during the Hadean after initial formation of this protocrust. Trace and rare earth element analyses of > 3.7 Ga grains indicate derivation from a source heavily influenced by the enriched mantle with little evidence for flux melting, and no clear evidence for deep melting. At ∼ 3.7 Ga, we observe an average ε_HfT increase indicating new additions of juvenile felsic material. These zircons still show predominantly mantle-like trace elements, but with the appearance of some arc-like signatures and evidence for crustal thickening. This period of crustal reorganization speaks towards a shift in geodynamic regime characterized by the onset of communication between the mantle and the crust from which the zircons formed at this location. The presence of long-lived, mantle-derived protocrust in both India and South Africa appears to suggest the possibility of a local stagnant lid, albeit more data is necessary to confirm this. The presence of a transition of ε_HfT data globally may point towards an important, diachronous period of crustal reorganization 3.9 – 3.6 Ga ago.

由于冥古宙时期岩石记录的缺乏，人们对早期地壳化学和地球动力学知之甚少。为了更好地了解冥古宙和太古宙的地球动力学变化，我们对兴兴克拉通古变质调性片麻岩~ 3.3 ~ 4.2 Ga锆石进行了锆石痕量锆石、稀土元素和Lu-Hf测量。在3.7 Ga的锆石中，我们发现亚球粒锆石εHfT呈下降趋势，在该原地壳初始形成后的冥古宙没有新的地壳物质加入的迹象。对>； 3.7 Ga颗粒的痕量和稀土元素分析表明，其来源受到富集地幔的严重影响，几乎没有通量熔融的证据，也没有深部熔融的明确证据。在~ 3.7 Ga，我们观察到平均εHfT增加，表明新添加了幼长英质物质。这些锆石仍主要显示出地幔样的微量元素，但出现了一些弧状特征和地壳增厚的证据。这一时期的地壳重组预示着地球动力学机制的转变，其特征是地幔和地壳之间开始交流，锆石由此形成。印度和南非存在着寿命较长的、源自地幔的原地壳，这似乎表明当地可能存在一个停滞的地壳盖，尽管需要更多的数据来证实这一点。全球范围内εHfT数据的转变可能指向3.9 ~ 3.6 Ga前一个重要的地壳重组历时期。

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引用次数: 0

Dual controls on lithospheric dripping: The role of mantle flow and orogen scale 岩石圈滴水的双重控制：地幔流和造山带尺度的作用

IF 4.8 1区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Earth and Planetary Science Letters

Pub Date : 2025-12-31 DOI: 10.1016/j.epsl.2025.119795

Qiuling Wang , Huilin Wang , Zhuang Li

Lithospheric dripping is a fundamental mechanism for recycling thickened lithosphere in orogens, but its dynamic controls remain incompletely understood. Classical models emphasizing intra-lithospheric dynamics predict symmetric lithosphere downwelling with coupled surface subsidence/uplift and volcanic activities, consistent with observations in small orogens. However, these models cannot explain the asymmetric dripping geometries and spatially decoupled magmatic-topographic signals observed in some large orogens. In this study, we use numerical models to investigate how mantle flow interacts with different orogenic architectures to modulate dripping styles. Our results show that thin and cold orogens maintain strong intra-lithospheric coupling that restricts mantle flow influence, producing classical dripping behavior characterized by localized, near-vertical instability descent and symmetric surface responses. In contrast, thick, hot, and moderately wide orogens with weak intra-lithospheric viscous coupling enable mantle flow to entrain and amplify lithospheric drips, resulting in extensive lithospheric thinning and laterally offset topographic and magmatic responses. Orogen width influences the amount and extent of lithospheric thinning. Broad orogens that maintain a high lithospheric viscosity result in more localized removal. Lithosphere thinning is restricted to drip-adjacent zones. These results can reconcile the diverse dripping styles and surface responses observed in various orogens, demonstrating that lithospheric dripping is a tiered process governed by the interplay of mantle flow and orogen-scale properties, where orogenic thermal-mechanical characteristics control sensitivity to basal flow. The results offer new insights into understanding mantle-lithosphere interactions and scale-dependent orogenic evolution.

岩石圈滴落是造山带岩石圈增厚再循环的基本机制，但其动力学控制机制尚不完全清楚。强调岩石圈内动力学的经典模型预测岩石圈的对称下移与地表沉降/隆升和火山活动的耦合，与小造山带的观测结果一致。然而，这些模型不能解释在一些大型造山带观测到的不对称滴状几何和空间解耦的岩浆地形信号。在这项研究中，我们使用数值模型来研究地幔流动如何与不同的造山带结构相互作用以调节滴水方式。研究结果表明，薄造山带和冷造山带保持着强烈的岩石圈内耦合，限制了地幔流的影响，形成了以局部、近垂直不稳定下降和对称地表响应为特征的经典滴水行为。相比之下，厚、热、宽适中的造山带与较弱的岩石圈内黏性耦合使地幔流动夹带并放大岩石圈滴液，导致岩石圈广泛变薄和横向偏移的地形和岩浆响应。造山带宽度影响岩石圈减薄的数量和程度。维持高岩石圈粘度的宽造山带导致更局部的去除。岩石圈减薄仅限于与水滴相邻的区域。这些结果与在不同造山带观测到的不同滴注样式和地表响应相一致，表明岩石圈滴注是一个受地幔流和造山带尺度性质相互作用支配的分层过程，造山带热力学特征控制着对基流的敏感性。研究结果为理解地幔-岩石圈相互作用和规模依赖性造山演化提供了新的见解。

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引用次数: 0

A model for Cenozoic seawater chemistry and carbon cycling 新生代海水化学与碳循环模式

IF 4.8 1区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Earth and Planetary Science Letters

Pub Date : 2025-12-31 DOI: 10.1016/j.epsl.2025.119811

Laurence A. Coogan, Stan E. Dosso

We present a model for the evolution of seawater chemistry and carbon cycling over the Cenozoic forced by changes in global mean temperature, continental weatherability, ocean crust accretion and solid Earth CO₂ degassing. The model tracks fluxes from continental silicate and carbonate weathering, seafloor weathering, marine silicate diagenesis, high-temperature hydrothermal circulation and carbonate sediment formation. The carbon system in the ocean is tracked through alkalinity (ALK) and dissolved inorganic carbon (DIC) fluxes allowing the entire carbon system to be calculated. The model has 48 parameters that are treated as unknowns, and we use a Bayesian inversion to determine the probable range of parameter values. Reasonable fits to reconstructions of Cenozoic seawater compositions (e.g., Mg, Ca, δ⁷Li, ⁸⁷Sr/⁸⁶Sr) and pCO₂ records are achieved. Consistent with other studies that consider the carbon system in seawater, the model results have limited change in seawater DIC and ALK over the Cenozoic. Key results include that the: (i) decrease in pCO₂ over the Cenozoic is driven by changing ocean chemistry (increased ratio of ALK to DIC) without a systematic change in the total carbon content of the ocean-atmosphere system, and (ii) CO₂ degassing rate and pCO₂ are decoupled. These results are inconsistent with commonly used geological carbon cycle models (e.g., GEOCARB, COPSE) but are readily understood in terms of seawater carbon chemistry and carbon cycling. Decreasing the Ca content of seawater at the same time as deepening the carbonate compensation depth requires increasing the carbonate ion concentration in the deep ocean; in the models this results from an increased ratio of ALK to DIC.

我们建立了一个受全球平均温度变化、大陆气候、海洋地壳增生和固体地球CO2脱气影响的新生代海水化学和碳循环演化模型。该模型跟踪了大陆硅酸盐和碳酸盐风化、海底风化、海相硅酸盐成岩作用、高温热液循环和碳酸盐沉积形成的通量。通过碱度（ALK）和溶解无机碳（DIC）通量来跟踪海洋中的碳系统，从而计算出整个碳系统。该模型有48个参数被视为未知数，我们使用贝叶斯反演来确定参数值的可能范围。对重建的新生代海水成分（如Mg、Ca、δ7Li、87Sr/86Sr）和pCO2记录进行了较好的拟合。与其他考虑海水碳系统的研究结果一致，该模式的结果显示新生代海水DIC和ALK的变化有限。主要结果包括：(1)新生代pCO2的减少是由海洋化学变化（ALK / DIC比值增加）驱动的，而海洋-大气系统总碳含量没有系统变化；(2)CO2脱气速率与pCO2解耦。这些结果与常用的地质碳循环模型（如GEOCARB、COPSE）不一致，但在海水碳化学和碳循环方面很容易理解。在加深碳酸盐补偿深度的同时降低海水中Ca含量，需要增加深海中的碳酸盐离子浓度；在模型中，这是由于ALK与DIC的比值增加。

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引用次数: 0

Ancient, buoyant mantle under the Sierra Leone Ridge in the equatorial Atlantic 赤道大西洋塞拉利昂海岭下古老的浮力地幔

IF 4.8 1区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Earth and Planetary Science Letters

Pub Date : 2025-12-31 DOI: 10.1016/j.epsl.2025.119812

Camilla Sani , Alessio Sanfilippo , Felix Genske , Carlotta Ferrando , Daniele Brunelli , Anna Cipriani , Alexander Peyve , Sergey Skolotnev , Marco Ligi , Andreas Stracke

The Sierra Leone Ridge is the equatorial portion of the Mid-Atlantic Ridge (MAR) between the St. Paul (0–1°N) and Doldrums (7–9°N) Fracture Zones. At ∼80 Ma, a submarine plateau –the Sierra Leone Rise which is now located off-ridge on the African plate and the Céarà Rise on the South American plate– formed due to excess magma production. Incompatible element-enriched MORB with high Sr-Pb but low Nd isotope ratios suggests that the high magma production could result from the interaction of a mantle plume with the Sierra Leone Ridge, the so-called Sierra Leone mantle plume that may now be centered at ∼1.7°N along the MAR. In order to define the nature of the mantle source beneath the Sierra Leone Ridge, we present major-trace element concentrations and radiogenic isotope ratios from abyssal peridotites and MORB from 4 to 7°N along the MAR. High Hf isotope ratios are preserved in clinopyroxenes from abyssal peridotites (Ɛ_Hf = 12–54), indicating that the mantle beneath the Sierra Leone Ridge underwent extensive melting several 10⁸–10⁹ years before remelting under the present MAR. Most peridotites have high Ɛ_Hf, but low Ɛ_Nd similar to MORBs, although some extend to unusually low Ɛ_Nd of ∼-6. We argue that these peridotites not only melted, but were also re-enriched in compatible elements concurrent to melting in the past, and that such incompatible element re-enriched peridotites are now the main component of the sub-ridge mantle in the Sierra Leone area. Extensive remelting of ancient, incompatible element re-enriched peridotite that is compositionally buoyant, in addition to minor amounts of recycled crust, may therefore have caused the abundant magmatism that characterizes this portion of the MAR since formation of the Sierra Leone and Céarà Rise ∼80 Ma ago, and accounts for its elevated topography.

塞拉利昂海脊是中大西洋海脊（MAR）的赤道部分，位于圣保罗断裂带（0-1°N）和低潮断裂带（7-9°N）之间。在~ 80 Ma，海底高原——现在位于非洲板块的塞拉利昂隆起和南美洲板块的csamaracom隆起——由于过量的岩浆产生而形成。具有高Sr-Pb和低Nd同位素比率的不相容元素富集MORB表明，高岩浆产量可能是地幔柱与塞拉利昂山脊相互作用的结果，所谓的塞拉利昂地幔柱现在可能集中在沿mar的~ 1.7°N。我们从4 ~ 7°N的深海橄榄岩和MORB中获得了主要微量元素的浓度和放射性成因同位素比值。深海橄榄岩的斜斜辉石中保存了较高的Hf同位素比值（ƐHf = 12-54），表明塞拉利昂山脊下的地幔在10⁸-10⁹年的时间里经历了广泛的融化，然后在现在的mar下重新融化。大多数橄榄岩的ƐHf高，ƐNd低，与MORB相似，尽管有些橄榄岩的ƐNd低至~ -6。我们认为，这些橄榄岩在过去不仅熔融，而且在熔融的同时还被相容元素重新富集，并且这种不相容元素重新富集的橄榄岩现在是塞拉利昂地区次脊地幔的主要组成部分。古不相容元素再富集橄榄岩的大量重熔，以及少量的再循环地壳，可能导致了自塞拉利昂和csamuaros隆起形成以来的丰富岩浆活动，这些岩浆活动是MAR的这一部分的特征，并解释了其隆起的地形。

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引用次数: 0

Cascade reservoirs seismicity: a unique dynamical system 层叠储层地震活动性：一个独特的动力系统

IF 4.8 1区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Earth and Planetary Science Letters

Pub Date : 2025-12-30 DOI: 10.1016/j.epsl.2025.119815

Guangyao Yin , Huai Zhang , Lipeng He , Pei He , Yaolin Shi

China's unique cascade reservoir system employs coordinated scheduling to regulate water storage and discharge, significantly influencing regional dynamics. However, studies investigating the potential seismic hazards induced by the cascading effects of multiple reservoirs remain limited. The Xiangjiaba and Xiluodu cascade reservoirs, located downstream along the Jinsha River in southwestern China, a region characterized by significant tectonic activity, are geographically connected in series. In this work, we first examine the spatiotemporal distribution of seismicity in the vicinity of the reservoirs. Subsequently, we develop a three-dimensional poroelastic finite-element model of the cascade-reservoir region that explicitly incorporates fault geometries and typical geological features. This model is adopted to estimate the pore-pressure evolution in association with elastic Coulomb stress changes under a variety of impoundment scenarios. Our results reveal that these two reservoirs exhibit significant concurrent influences on each other, as well as the subsequent regional seismicity. In particular, the changes in Coulomb stress and pore pressure do not accumulate consistently with respect to time. Their interaction induces a redistribution of the crustal stress field through reservoir-reservoir coupling, suggesting that the cascade-reservoir system operates essentially as an independent and exclusive dynamic system. Notably, seismicity appears to be governed not merely by static pore-pressure magnitudes but by the rate of pore-pressure increase, underscoring the importance of dynamic pore-pressure evolution in seismic triggering processes. These findings enhance the understanding of how cascade reservoirs may perturb crust stress fields and seismic activity, providing a theoretical basis for future reservoir design, operation, and seismic risk assessment in complex and seismically active geological settings.

中国独特的梯级水库系统采用协调调度来调节储水量和排水量，对区域动态具有重要影响。然而，对多储层级联效应引起的潜在地震危害的研究仍然有限。向家坝和溪洛渡梯级水库位于中国西南金沙江下游，是一个构造活动明显的地区，在地理上是串联的。在这项工作中，我们首先研究了水库附近地震活动的时空分布。随后，我们建立了一个明确包含断层几何形状和典型地质特征的级联储区三维孔隙弹性有限元模型。采用该模型估计了不同蓄水情景下孔隙压力随弹性库仑应力变化的演化规律。研究结果表明，这两个储层具有明显的相互影响，并对后续的区域地震活动产生影响。特别是，库仑应力和孔隙压力的变化并不随时间累积一致。它们的相互作用通过储层-储层耦合导致了地壳应力场的重新分布，表明级联-储层系统本质上是一个独立的排他性动力系统。值得注意的是，地震活动性似乎不仅受静态孔隙压力大小的控制，而且受孔隙压力增加速度的控制，这强调了动态孔隙压力演化在地震触发过程中的重要性。这些发现增强了对级联储层如何干扰地壳应力场和地震活动的理解，为未来复杂和地震活跃地质环境下的储层设计、运行和地震风险评估提供了理论基础。

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引用次数: 0

Generation of large transient porosity at the brittle to semi-ductile transition 在脆性向半韧性转变时产生大的瞬态孔隙

IF 4.8 1区地球科学 Q1 GEOCHEMISTRY & GEOPHYSICS

Earth and Planetary Science Letters

Pub Date : 2025-12-30 DOI: 10.1016/j.epsl.2025.119805

Erina Prastyani , Benoît Cordonnier , François Renard

Fluid circulation within Earth’s crust is contingent on the presence of connected porosity. Yet, at depths near the brittle to ductile transition regimes, where the base of the seismogenic zone is located, high pressure compacts the rock, reducing porosity and inhibiting fluid circulation. At greater depths, plastic mechanisms during ductile deformation further reduce the likelihood of porosity generation. In this study, we experimentally simulated the brittle to semi-ductile transition in Carrara marble by performing triaxial deformation experiments coupled with time-lapse 3D synchrotron X-ray microtomography at five confining pressures, ranging from 5 MPa to 70 MPa at room temperature and tracked the evolution of porosity over time. Contrary to the prevailing belief, our results show that porosity increases with increasing axial stress at stresses corresponding to the brittle to semi-ductile transition, where fluid circulation is thought to be impeded. In both the semi-brittle and semi-ductile regimes, the total porosity (averaged over the entire sample) exhibits similar values, close to 18%, increasing from an initial porosity of approximately 1% at equivalent axial strain. Although the porosity is comparable, the dominant deformation mechanisms differ: localized shear zones and distributed microcracking characterize the semi-brittle regime, whereas distributed microcracking, without localization, becomes more prominent in the semi-ductile regime. Our findings reveal the formation of high porosity within the semi-brittle and semi-ductile regimes and offer new insight into how this porosity, interpreted as transient within the crust, may enable fluid circulation at the base of the seismogenic zone in Earth’s crust.

地壳内的流体循环取决于连通孔隙的存在。然而，在靠近脆性到韧性过渡区的深度，也就是孕震带底部的位置，高压会压实岩石，降低孔隙度，抑制流体循环。在更深的深度，塑性变形过程中的塑性机制进一步降低了孔隙产生的可能性。在本研究中，我们通过实验模拟了Carrara大理岩在5 MPa至70 MPa的室温围压下的三轴变形实验，并结合延时3D同步加速器x射线微断层扫描技术，模拟了大理岩脆性向半韧性转变的过程，并跟踪了孔隙度随时间的演变。与普遍的看法相反，我们的研究结果表明，在脆性到半韧性转变的应力中，孔隙度随着轴向应力的增加而增加，流体循环被认为受到阻碍。在半脆性和半延性状态下，总孔隙度（整个样品的平均值）显示出相似的值，接近18%，在等效轴向应变下的初始孔隙度约为1%。虽然孔隙度相似，但主要的变形机制不同：局部剪切带和分布微裂纹是半脆性的特征，而分布微裂纹在半延性中更加突出，而非局部化。我们的发现揭示了高孔隙度在半脆性和半韧性体系内的形成，并提供了新的见解，解释了这种孔隙度在地壳内的短暂性，如何使地壳地震带底部的流体循环成为可能。

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引用次数: 0