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1.
近临界特性的地层水及其对烃源岩生排烃过程的影响 总被引：2，自引：0，他引：2
研究利用特制的地层孔隙热压模拟实验装置, 开展了模拟地层孔隙空间高压液态水热体系烃源岩生排烃模拟实验.模拟实验施加的流体压力为38±2 MPa, 温度为290~390 ℃.模拟实验结果显示了有关高压液态水及其与之相联系的流体压力和孔隙空间等因素对烃源岩生排烃影响作用的一些重要现象, 实验发现高压液态水介质条件有利于液态油的生成和保存, 不利于液态油向气态烃的转化, 而且干酪根的生烃潜力和排油效率有一定的提高.这些新的实验现象可能主要与近临界特性的高压液态地层水的作用有关, 进一步推断近临界特性的高压液态水参与干酪根向油气的转化反应, 增加了水对油气的溶解能力.在地下实际烃源岩生排烃的温压(100~200 ℃, 30~120 MPa)条件下, 岩石孔隙中的地层水是一种相对低温高压压缩液态水, 这种地层水可能具有近临界特性, 对烃源岩生排烃过程有重要影响.但目前对这种现象的机理和石油地质意义还知之较少.因此, 加强高压地层水近临界条件下烃源岩生排烃热压模拟实验研究, 对进一步深入理解地层条件下的近临界水介质、流体压力、孔隙空间因素对生排烃过程的影响, 深化烃源岩生排烃机理的探讨, 建立地质尺度上的烃源岩生排烃动力学模型, 都具有重要的理论和实际意义. 相似文献
2.
倪怀玮 《矿物岩石地球化学通报》2020,39(3):前插1-前插2,443-447
在地球深部(特别是俯冲带)的高温高压条件下,硅酸盐和水的相互溶解能力增强,可以形成成分介于常规硅酸盐熔体和富水流体之间的超临界地质流体。超临界流体的形成条件主要取决于岩石-H_2O体系的临界曲线、湿固相线和第二临界端点的位置。超临界地质流体具有特殊的物理化学性质,能够在促成俯冲带物质循环、迁移和富集元素成矿、引发中深源地震、影响地表宜居性演化等方面发挥关键作用。通过高温高压实验、分子模拟计算、天然岩石和矿床样品等手段研究超临界地质流体的性质和效应仍存在巨大挑战,亟需变革性实验和计算技术突破。 相似文献
3.
在地球深部(特别是俯冲带)的高温高压条件下,硅酸盐和水的相互溶解能力增强,可以形成成分介于常规硅酸盐熔体和富水流体之间的超临界地质流体。超临界流体的形成条件主要取决于岩石-H2O体系的临界曲线、湿固相线和第二临界端点的位置。超临界地质流体具有特殊的物理化学性质,能够在促成俯冲带物质循环、迁移和富集元素成矿、引发中深源地震、影响地表宜居性演化等方面发挥关键作用。通过高温高压实验、分子模拟计算、天然岩石和矿床样品等手段研究超临界地质流体的性质和效应仍存在巨大挑战,亟需变革性实验和计算技术突破。 相似文献
4.
《矿物岩石地球化学通报》2017,(1)
水是地球岩浆中的一种主要挥发分。水的存在导致岩石的熔融温度降低,其根本原因在于水易溶于硅酸盐熔体。本文总结了在地球岩石圈温压条件下,水在硅酸盐熔体中的赋存形式、溶解度与水对熔体物理性质的影响。熔体中溶解的水以H_2O分子和OH形式存在。水在熔体中的溶解度随压力的升高而增大。当温压条件位于含水硅酸盐体系的临界曲线之上时,甚至可能形成成分介于硅酸盐熔体和富水流体之间的超临界流体。水使熔体的密度和黏度降低,更易于脱离源区向上运移。水使元素扩散加快,有利于晶体和气泡的生长。水导致熔体的电导率升高,使部分熔融造成的电导率异常更加显著。水对硅酸盐熔体迁移性质的影响以及水的溶解行为都与水的种型分异反应密切相关。在研究与熔融有关的地质过程时必须充分考虑水的作用。 相似文献
5.
本文对榴辉岩部分熔融过程中不同同位素体系是否存在分馏这一当前研究热点进行了综述.榴辉岩作为研究洋陆俯冲、超高压变质以及壳幔相互作用的主要岩石类型,其部分熔融与地壳增生、板片折返过程以及俯冲隧道中元素的迁移分配等具有紧密的联系.作为典型的高压-超高压变质岩石,榴辉岩可通过俯冲带将壳源信息携带至地幔深部,影响地慢的化学组成... 相似文献
6.
深俯冲碳酸盐化泥质岩的部分熔融行为研究是探索地球深部碳循环必不可少的方向之一,对地球深部物质循环、岩浆形成以及地幔化学成分不均一等过程起着不容忽视的作用。本文利用多顶砧大压机探索了6.0 GPa、800~1 600℃下碳酸盐化泥质岩的部分熔融行为,实验产物主要包括石榴子石、单斜辉石、柯石英、蓝晶石、碳酸盐矿物、多硅白云母以及熔体。碳酸盐矿物为方解石和菱镁矿,存在于6.0 GPa固相线以下的实验产物中。相对于同等压力下其它碳酸盐化体系,本文实验体系具有最低的固相线。部分熔融产生的熔体为硅酸盐熔体,且随着温度的升高,熔体比例逐渐增加,熔体成分也发生了明显的变化。 相似文献
7.
热解生烃实验是研究油气生成机理与定量评价烃源岩生烃潜力的重要方法.烃源岩热解生烃模拟结果不仅与温度、压力和时间等因素有关,而且与地层孔隙水及压实成岩作用等地质因素密切相关.采用高压流体和高压釜(低压水蒸气)两种生烃热模拟方法对低成熟海相二叠统大隆组(P2d)黑色泥岩进行了热解生烃实验模拟.对比分析两组实验结果表明地层孔隙热解实验有利于液态油的生成,不利于液态油向气态烃的转化,并极大地提高了干酪根的生油气潜力,显示了高压液态水、流体压力和孔隙空间等地质因素对烃源岩中有机质热成熟生烃反应的重要影响.这种影响可能与高压液态水的近临界特性有关,近临界特性地层水的参与改变了干酪根热力生烃反应的物理化学行为.推断在实际地质温压(100~200 ℃,30~120 MPa)条件下,烃源岩孔隙中的地层水是一种相对低温高压液态水,具有水的近临界物理化学特性,因此高压流体生烃热模拟实验与实际地层情况更为接近,能更有效地评价烃源岩生烃潜力. 相似文献
8.
夏群科 《矿物岩石地球化学通报》2015,(3)
<正>"水"在地幔的矿物中主要以晶格缺陷中的结构水形式存在,尽管其含量可能只有"10-6"的量级,但是这些微量的结构水会强烈的影响深部地幔矿物与岩石的化学物理性质,如矿物结构、岩石应变强度、部分熔融温度等,进而影响地幔的动力学性质和地球物理特征。大洋板块俯冲是"水"进入深部地幔的重要途径,各种高压、超高压含水相矿物是俯冲过程中"水"进入地幔的重要载体。因此,合成与研究超高压含水相硅酸盐矿物及其相变过程一直是实验岩石学的热点。 相似文献
9.
作为"非传统稳定同位素"家族成员,钙同位素正受到国际地学界日益广泛的关注.钙是主要的造岩元素,也是生物必需的元素.钙在地球各圈层广泛分布,研究钙同位素的地球化学行为将有助于提高我们对各种生物过程和地质过程的认识.钙同位素测定主要采用热电离质谱仪(TIMS)和多接收电感耦合等离子体质谱仪(MC-ICP-MS),分别表示为δ44/40 Ca和δ44/42Ca.目前自然界可观测到的δ44/40Ca变化范围为-2.0‰～6.75‰,约8.7‰.本文系统介绍了近年来钙同位素分析中样品溶解、化学分离、质谱测定以及高温地质过程中的钙同位素分馏及其地质应用等方面的研究成果,尤其对钙同位素在碳酸岩-共生硅酸盐岩研究中的意义、钙同位素组成以及取得的主要认识作了较为全面的介绍.阐述了放射成因40 Ca、部分熔融作用/分离结晶作用、地壳同化作用、古俯冲碳酸盐循环、热液蚀变作用、岩浆起源深度等对碳酸岩、硅酸盐岩的钙同位素组成造成的影响.最后,通过系统对比碳酸岩-共生硅酸盐岩的锂、镁、钙同位素研究成果,认为应该开展多元同位素体系的联合示踪.由于不同同位素体系存在相似性和差异性,而多元同位索体系相结合能有效地加强优势互补,将是同位素地球化学研究发展的一种必然趋势. 相似文献
10.
铬铁矿预富集和上地幔部分熔融关系的实验研究 总被引：5，自引：0，他引：5
用合成地幔岩为原始材料，在温度１２２５℃和严格控制氧分压１０＾－５－１０＾１２ａｔｍ条件下，对上地幔部分熔融作用与铬铁矿预富集关系进行实验研究。实验结果表明：（１）在达到稳态熔融结构时５％－８％的玄武质硅酸盐熔体主要存在矿物三联点之间，它为铬元素从地幔岩中萃取运移和预富集提供了先决条件；（２）在部分熔融过程中原岩的尖晶石和辉石提供的铬元素相结合，形成了富铬尖晶石和铬铁矿。 相似文献
11.
俯冲带中H_2O和K的深循环:对碰撞后富钾岩浆成因研究的启示 总被引：5，自引：0，他引：5
在俯冲过程中形成的超高压单斜辉石 (>5GPa)含一定量的H2 O和K2 O ,它因此能把地球浅部的水和钾携带到地幔深处。超高压单斜辉石在折返过程中以两种方式释放其中的H2 O和K2 O :(1)在低温环境下进入与单斜辉石共生的出溶矿物相如金云母、角闪石、多硅白云母、钾长石等 ;(2 )当温度足够高到发生部分熔融时 ,H2 O和K2 O将进入熔体相 ,形成富钾岩浆。超高压变质岩石能不能在其折返过程中产生部分熔融主要取决于折返的 p T轨迹。俯冲板片部分熔融形成熔体的性质在很大程度上取决于变质岩的部分熔融程度。虽然经受 p <5GPa变质作用的榴辉岩通过极低程度的部分熔融也有可能形成富钾熔体 ,但由于这类榴辉岩所能携带的K2 O和H2 O相对比较少 ,因此不可能产生大规模富钾熔体 ,但可能形成相对富Na的岩浆。超高压单斜辉石 (>5GPa)部分熔融产生的富钾岩浆可以解释碰撞后富钾岩浆的成因 ,这种富钾岩浆的形成深度一般较大 (位于～ 10 0km的地幔 )。而绿辉石部分熔融形成相对富钠熔体的深度相对较浅。从单斜辉石中释放出来的H2 O和K2 O能够合理地解释大陆碰撞后富钾岩浆的成因 ,通过俯冲板片折返过程的脱水和取钾反应 ,俯冲和折返过程与碰撞后岩浆活动密切联系在一起而成为一个整体。 相似文献
12.
Partial melting of ultrahigh-pressure metamorphic rocks at convergent continental margins: Evidences,melt compositions and physical effects 总被引：2，自引：0，他引：2
Ultrahigh-pressure(UHP) metamorphic rocks are distinctive products of crustal deep subduction,and are mainly exposed in continental subduction-collision terranes. UHP slices of continental crust are usually involved in multistage exhumation and partial melting, which has obvious influence on the rheological features of the rocks, and thus significantly affect the dynamic behavior of subducted slices. Moreover,partial melting of UHP rocks have significant influence on element mobility and related isotope behavior within continental subduction zones, which is in turn crucial to chemical differentiation of the continental crust and to crust-mantle interaction.Partial melting can occur before, during or after the peak metamorphism of UHP rocks. Post-peak decompression melting has been better constrained by remelting experiments; however, because of multiple stages of decompression, retrogression and deformation, evidence of former melts in UHP rocks is often erased. Field evidence is among the most reliable criteria to infer partial melting. Glass and nanogranitoid inclusions are generally considered conclusive petrographic evidence. The residual assemblages after melt extraction are also significant to indicate partial melting in some cases. Besides field and petrographic evidence, bulk-rock and zircon trace-element geochemical features are also effective tools for recognizing partial melting of UHP rocks. Phase equilibrium modeling is an important petrological tool that is becoming more and more popular in P-T estimation of the evolution of metamorphic rocks; by taking into account the activity model of silicate melt, it can predict when partial melting occurred if the P-T path of a given rock is provided.UHP silicate melt is commonly leucogranitic and peraluminous in composition with high SiO_2,low MgO, FeO, MnO, TiO_2 and CaO, and variable K_2 O and Na_2 O contents. Mineralogy of nanogranites found in UHP rocks mainly consists of plagioclase + K-feldspar + quartz, plagioclase being commonly albite-rich.Trace element pattern of the melt is characterized by significant enrichment of large ion lithophile elements(LILE), depletion of heavy rare earth elements(HREE) and high field strength elements(HFSE),indicating garnet and rutile stability in the residual assemblage. In eclogites, significant Mg-isotope fractionation occurs between garnet and phengite; therefore, Mg isotopes may become an effective indicator for partial melting of eclogites. 相似文献
13.
Experimental Study of Partial Melting of Mantle Peridotite--A Discussion about the Genesis of Silica-rich Fluids (Melts) 总被引：1，自引：0，他引：1
LI Jianping 《《地质学报》英文版》1999,73(4):395-403
Experiments on partial melting of mantle lherzolite have been realized at 0.6 and 1.0 GPa and the chemical compositional variations of melts during different melting stages have been first discussed. The results show that the trends of variations in SiO2, CaO, Al2O3, Na2O and TiO2 are different at different melting stages. The melts produced at lower pressure are richer in SiO2 than those at higher pressure. The mantle-derived silica-rich fluids (silicate melts) are polygenetic, but the basic and intermediate-acid silicate melts in mantle peridotite xenoliths from the same host rocks, which have equivalent contents of volatile and alkali components and different contents of other components, should result from in-situ (low-degree) partial melting of mantle peridotite under different conditions (e.g. at different depths, with introduction of C-O-H fluids or in the presence of metasomatic minerals). The intermediate-acid melts may be the result of partial melting (at lower pressure) Opx + Sp + K-Na-rich fluid±(Amphi)±(Phlog)= Ol+melt.But the intermediate-acid magmas cannot be produced from the partial melting of normal mantle peridotite unless the crustal materials are introduced to some extent. 相似文献
14.
The effect of H<Subscript>2</Subscript>O on the olivine liquidus of basaltic melts: experiments and thermodynamic models 总被引：2，自引：2，他引：0
We designed and carried out experiments to investigate the effect of H2O on the liquidus temperature of olivine-saturated primitive melts. The effect of H2O was isolated from other influences by experimentally determining the liquidus temperatures of the same melt composition
with various amounts of H2O added. Experimental data indicate that the effect of H2O does not depend on pressure or melt composition in the basaltic compositional range. The influence of H2O on melting point lowering can be described as a polynomial function
This expression can be used to account for the effect of H2O on olivine-melt thermometers, and can be incorporated into fractionation models for primitive basalts. The non-linear effect
of H2O indicates that incorporation of H2O in silicate melts is non-ideal, and involves interaction between H2O and other melt components. The simple speciation approach that seems to account for the influence of H2O in simple systems (albite-H2O, diopside-H2O) fails to describe the mixing behavior of H2O in multi-component silicate melts. However, a non-ideal solution model that treats the effect of H2O addition as a positive excess free energy can be fitted to describe the effect of melting point lowering. 相似文献
15.
Mineral/melt partitioning of trace elements during hydrous peridotite partial melting 总被引：6，自引：4，他引：2
This experimental study examines the mineral/melt partitioning of incompatible trace elements among high-Ca clinopyroxene, garnet, and hydrous silicate melt at upper mantle pressure and temperature conditions. Experiments were performed at pressures of 1.2 and 1.6 GPa and temperatures of 1,185 to 1,370 °C. Experimentally produced silicate melts contain up to 6.3 wt% dissolved H 2O, and are saturated with an upper mantle peridotite mineral assemblage of olivine+orthopyroxene+clinopyroxene+spinel or garnet. Clinopyroxene/melt and garnet/melt partition coefficients were measured for Li, B, K, Sr, Y, Zr, Nb, and select rare earth elements by secondary ion mass spectrometry. A comparison of our experimental results for trivalent cations (REEs and Y) with the results from calculations carried out using the Wood-Blundy partitioning model indicates that H 2O dissolved in the silicate melt has a discernible effect on trace element partitioning. Experiments carried out at 1.2 GPa, 1,315 °C and 1.6 GPa, 1,370 °C produced clinopyroxene containing 15.0 and 13.9 wt% CaO, respectively, coexisting with silicate melts containing ~1–2 wt% H 2O. Partition coefficients measured in these experiments are consistent with the Wood-Blundy model. However, partition coefficients determined in an experiment carried out at 1.2 GPa and 1,185 °C, which produced clinopyroxene containing 19.3 wt% CaO coexisting with a high-H 2O (6.26±0.10 wt%) silicate melt, are significantly smaller than predicted by the Wood-Blundy model. Accounting for the depolymerized structure of the H 2O-rich melt eliminates the mismatch between experimental result and model prediction. Therefore, the increased Ca 2+ content of clinopyroxene at low-temperature, hydrous conditions does not enhance compatibility to the extent indicated by results from anhydrous experiments, and models used to predict mineral/melt partition coefficients during hydrous peridotite partial melting in the sub-arc mantle must take into account the effects of H 2O on the structure of silicate melts. 相似文献
16.
The influence of melt structure on trace element partitioning near the peridotite solidus 总被引：8，自引：8，他引：0
This experimental study examines the mineral/melt partitioning of Na, Ti, La, Sm, Ho, and Lu among high-Ca clinopyroxene, plagioclase, and silicate melts analogous to varying degrees of peridotite partial melting. Experiments performed at a pressure of 1.5 GPa and temperatures of 1,285 to 1,345 °C produced silicate melts saturated with high-Ca clinopyroxene, plagioclase and/or spinel, and, in one case, orthopyroxene and garnet. Partition coefficients measured in experiments in which clinopyroxene coexists with basaltic melt containing ~18 to 19 wt% Al2O3 and up to ~3 wt% Na2O are consistent with those determined experimentally in a majority of the previous studies, with values of ~0.05 for the light rare earths and of ~0.70 for the heavy rare earths. The magnitudes of clinopyroxene/melt partition coefficients for the rare earth elements correlate with pyroxene composition in these experiments, and relative compatibilities are consistent with the effects of lattice strain energy. Clinopyroxene/melt partition coefficients measured in experiments in which the melt contains ~20 wt% Al2O3 and ~4 to 8 wt% Na2O are unusually large (e.g., values for Lu of up to 1.33±0.05) and are not consistent with the dependence on pyroxene composition found in previous studies. The magnitudes of the partition coefficients measured in these experiments correlate with the degree of polymerization of the melt, rather than with crystal composition, indicating a significant melt structural influence on trace element partitioning. The ratio of non-bridging oxygens to tetrahedrally coordinated cations (NBO/T) in the melt provides a measure of this effect; melt structure has a significant influence on trace element compatibility only for values of NBO/T less than ~0.49. This result suggests that when ascending peridotite intersects the solidus at relatively low pressures (~1.5 GPa or less), the compatibility of trace elements in the residual solid varies significantly during the initial stages of partial melting in response to the changing liquid composition. It is unlikely that this effect is important at higher pressures due to the increased compatibility of SiO2, Na2O, and Al2O3 in the residual peridotite, and correspondingly larger values of NBO/T for small degree partial melts.Editorial responsibility: T.L. Grove 相似文献
17.
Rainer Thomas Paul Davidson 《岩石学报》2007,23(1):15-20
This paper is focused on the progress in the determination of water in glasses and melt inclusions with Raman spectroscopy.Using the presented"Comparator Technique"the water content of a sample is determined by simple comparison with a known standard.A calibration curve is not necessary.Furthermore,with this technique the water concentration in silicate melt inclusions can be determined without exposing the inclusions for measurements.This is very important for extremely water-rich melt inclusions,which would loose H_2O on exposure. 相似文献
18.
We have experimentally investigated the kinetics of melting of an aplitic leucogranite (quartz+sodic plagioclase of ≈Ab90+K-feldspar+traces of biotite) at 690, 740, and 800°C, all at 200 MPa H2O. Leucogranite cylinders, 3.5 mm in diameter and 7 mm in length, were run in the presence of excess H2O using cold-seal pressure vessels for 11–2,925 h. At 690 and 740°C and any experimental time, and 800°C and short run times, silicate glass (melt at run conditions) occurs as interconnected films along most of the mineral boundaries and in fractures, with the predominant volume occurring along quartz/feldspars boundaries and quartz/plagioclase/K-feldspar triple junctions. Glass film thickness is roughly constant throughout a given experimental charge and increases with experimental temperature and run duration. The results indicate that H2O-saturated partial melting of a quartzo-feldspathic protolith will produce an interconnected melt phase even at very low degrees (<5 vol%) of partial melting. Crystal grain boundaries are therefore completely occluded with melt films even at the lowest degrees of partial melting, resulting in a change in the mechanism of mass transport through the rock from advection of aqueous vapor to diffusion through silicate melt. At 690 and 740°C the compositions of glasses are homogeneous and (at both temperatures) close to, but not on, the H2O-saturated 200 MPa haplogranite eutectic; glass compositions do not change with run duration. At 800°C glasses are heterogeneous and plot away from the minimum, although their molar ratios ASI (=mol Al2O3/CaO+Na2O+K2O) and Al/Na are constant throughout the entire charge at any experimental time. Glass compositions within individual 800°C experiments form linear trends in (wt%) normative quartz–albite–orthoclase space. The linear trends are oriented perpendicular to the 200 MPa H2O haplogranite cotectic line, reflecting nearly constant albite/orthoclase ratio versus variable quartz/feldspar ratio, and have endpoints between the 800°C isotherms on the quartz and feldspar liquidus surfaces. With increasing experimental duration the trends migrate from the potassic side of the minimum toward the bulk rock composition located on the sodic side, due to more rapid (and complete) dissolution of K-feldspar relative to plagioclase. The results indicate that partial melting at or slightly above the solidus (690–740°C) is interface reaction-controlled, and produces disequilibrium melts of near-minimum composition that persist metastably for up to at least 3 months. Relict feldspars show no change in composition or texture, and equilibration between melt and feldspars might take from a few to tens of millions of years. Partial melting at temperatures well above the solidus (800°C) produces heterogeneous, disequilibrium liquids whose compositions are determined by the diffusive transport properties of the melt and local equilibrium with neighboring mineral phases. Feldspars recrystallize and change composition rapidly. Partial melting and equilibration between liquids and feldspars might take from a few to tens of years (H2O-saturated conditions) at these temperatures well above the solidus. 相似文献
19.
In order to model the processes of formation of the highly alkaline (potassic) melts during the partial melting of the eclogite
nodules in kimberlites, experiments on the melting of the model and natural eclogites in presence of the H2O-CO2 and H2O-CO2-KCl fluids at 5 GPa and 1200 and 1300°C are performed. A comparative analysis of the phase relations in the systems with
H2O-CO2 and H2O-CO2-KCl demonstrate that KCl in the fluid equilibrated with eclogites intensifies their melting. It is related to both high Cl
concentration in the forming silicate melt (2.0–5.5 wt %) and its enrichment in K2O owing to the K-Na exchange reactions with the immiscible chloride melt. Because of these reactions, the K2O/Cl ratio in the melts increases with the KCl content in the system and reaches 2.5–3.5 in the silicate melts coexisting
with the immiscible chloride liquid. However, the ratio KCl/(H2O + CO2 + KCl) in the fluid does not influence on the ratio K2O/Cl in the melts. Thus, the solubility KCl in the melts, apparently, does not depend on presence of the H2O-CO2 fluid, at least, within the concentration range used in the experiments (up to 20 wt %). The experiments show that the deliberated
chloride liquid is necessary to form the potassium-rich chlorine-bearing silicate melts during the eclogite melting. It corresponds
to the KCl content in the system above 5 wt %. 相似文献
20.
高级变质岩中深熔作用的相平衡研究 总被引：3，自引：0，他引：3
深熔作用在高级变质岩中非常普遍并受到广泛关注。自20世纪90年代以来,随着变质相平衡研究的突破性发展,利用THERMOCALC程序和视剖面图方法可以定量研究固相线以上的熔体形成、熔体分馏和退变质反应。变质沉积岩中的熔融作用主要有三种机制饱和水固相线上的熔融、白云母脱水熔融和黑云母脱水熔融。在模拟泥质岩石的KFMASH体系和NCKFMASH体系中的相平衡计算表明,NCKFMASH体系中铁镁矿物的相平衡关系受KFMASH亚体系中矿物相平衡关系的控制,但KFMASH亚体系中固相线位置要比实际的高50~60℃。因此,模拟泥质岩石的固相线以上的相平衡关系最好在NCKFMASH或组分更多的体系中进行。相平衡研究表明麻粒岩相岩石的保存与熔体丢失有关;混合岩的形成过程包括部分熔融作用、不同程度熔体分凝与汲取和不同程度的逆反应和退变反应。 相似文献