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Journal articles on the topic 'Upper mantle melting'

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Published: 10 December 2022

Last updated: 28 January 2023

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1

Hier-Majumder, Saswata, and Benoit Tauzin. "Pervasive upper mantle melting beneath the western US." Earth and Planetary Science Letters 463 (April 2017): 25–35. http://dx.doi.org/10.1016/j.epsl.2016.12.041.

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2

KOSTOPOULOS, D. K. "Melting of the Shallow Upper Mantle: A New Perspective." Journal of Petrology 32, no. 4 (August 1, 1991): 671–99. http://dx.doi.org/10.1093/petrology/32.4.671.

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3

Schiano, Pierre, Bernard Bourdon, Robert Clocchiatti, Dominique Massare, Maria E. Varela, and Yan Bottinga. "Low-degree partial melting trends recorded in upper mantle minerals." Earth and Planetary Science Letters 160, no. 3-4 (August 1998): 537–50. http://dx.doi.org/10.1016/s0012-821x(98)00109-5.

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4

WASYLENKI, L. E. "Near-solidus Melting of the Shallow Upper Mantle: Partial Melting Experiments on Depleted Peridotite." Journal of Petrology 44, no. 7 (July 1, 2003): 1163–91. http://dx.doi.org/10.1093/petrology/44.7.1163.

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5

Xu, Man, Zhicheng Jing, Suraj K. Bajgain, Mainak Mookherjee, James A. Van Orman, Tony Yu, and Yanbin Wang. "High-pressure elastic properties of dolomite melt supporting carbonate-induced melting in deep upper mantle." Proceedings of the National Academy of Sciences 117, no. 31 (July 20, 2020): 18285–91. http://dx.doi.org/10.1073/pnas.2004347117.

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Deeply subducted carbonates likely cause low-degree melting of the upper mantle and thus play an important role in the deep carbon cycle. However, direct seismic detection of carbonate-induced partial melts in the Earth’s interior is hindered by our poor knowledge on the elastic properties of carbonate melts. Here we report the first experimentally determined sound velocity and density data on dolomite melt up to 5.9 GPa and 2046 K by in-situ ultrasonic and sink-float techniques, respectively, as well as first-principles molecular dynamics simulations of dolomite melt up to 16 GPa and 3000 K. Using our new elasticity data, the calculated VP/VSratio of the deep upper mantle (∼180–330 km) with a small amount of carbonate-rich melt provides a natural explanation for the elevated VP/VSratio of the upper mantle from global seismic observations, supporting the pervasive presence of a low-degree carbonate-rich partial melt (∼0.05%) that is consistent with the volatile-induced or redox-regulated initial melting in the upper mantle as argued by petrologic studies. This carbonate-rich partial melt region implies a global average carbon (C) concentration of 80–140 ppm. by weight in the deep upper mantle source region, consistent with the mantle carbon content determined from geochemical studies.

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6

Kimura, Takafumi, Kazuhito Ozawa, Takeshi Kuritani, Tsuyoshi Iizuka, and Mitsuhiro Nakagawa. "Thermal state of the upper mantle and the origin of the Cambrian-Ordovician ophiolite pulse: Constraints from ultramafic dikes of the Hayachine-Miyamori ophiolite." American Mineralogist 105, no. 12 (December 1, 2020): 1778–801. http://dx.doi.org/10.2138/am-2020-7160.

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Abstract Ophiolite pulses, which are periods of enhanced ophiolite generation and emplacement, are thought to have a relevance to highly active superplumes (superplume model). However, the Cambrian-Ordovician pulse has two critical geological features that cannot be explained by such a superplume model: predominance of subduction-related ophiolites and scarcity of plume-related magma activities. We addressed this issue by estimating the mechanism and condition of magma generation, including mantle potential temperature (MPT), from a ~500 Ma subduction-related ophiolite, the Hayachine-Miyamori ophiolite. We developed a novel method to overcome difficulties in global MPT estimation from an arc environment by using porphyritic ultramafic dikes showing flow differentiation, which have records of the chemical composition of the primitive magma, including its water content, because of their high pressure (~0.6 GPa) intrusion and rapid solidification. The solidus conditions for the primary magmas are estimated to be ~1450 °C, ~5.3 GPa. Geochemical data of the dikes show passive upwelling of a depleted mantle source in the garnet stability field without a strong influence of slab-derived fluids. These results, combined with the extensive fluxed melting of the mantle wedge prior to the dike formation, indicate sudden changes of the melting environment, its mechanism, and the mantle source from extensive fluxed melting of the mantle wedge to decompressional melting of the sub-slab mantle, which has been most plausibly triggered by a slab breakoff. The estimated MPT of the sub-slab mantle is ~1350 °C, which is very close to that of the current upper mantle and may reflect the global value of the upper mantle at ~500 Ma if small-scale convection maintained the shallow sub-slab mantle at a steady thermal state. We, therefore, conclude that the Cambrian-Ordovician ophiolite pulse is not attributable to the high temperature of the upper mantle. Frequent occurrence of slab breakoff, which is suggested by our geochemical compilation of Cambrian-Ordovician ophiolites, and subduction termination, which is probably related to the assembly of the Gondwana supercontinent, may be responsible for the ophiolite pulse.

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7

Green, T. H., E. H. Hauri, G. A. Gaetani, and J. Adam. "New calculations on water storage in the upper mantle, and implications for mantle melting models." Geochimica et Cosmochimica Acta 70, no. 18 (August 2006): A215. http://dx.doi.org/10.1016/j.gca.2006.06.432.

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8

Aiuppa, Alessandro, Federico Casetta, Massimo Coltorti, Vincenzo Stagno, and Giancarlo Tamburello. "Carbon concentration increases with depth of melting in Earth’s upper mantle." Nature Geoscience 14, no. 9 (August 5, 2021): 697–703. http://dx.doi.org/10.1038/s41561-021-00797-y.

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9

Dasgupta, Rajdeep, and Marc M. Hirschmann. "Melting in the Earth's deep upper mantle caused by carbon dioxide." Nature 440, no. 7084 (March 2006): 659–62. http://dx.doi.org/10.1038/nature04612.

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10

Karato, S. "Does partial melting reduce the creep strength of the upper mantle?" Nature 319, no. 6051 (January 1986): 309–10. http://dx.doi.org/10.1038/319309a0.

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11

Bagley, Brian, Anna M. Courtier, and Justin Revenaugh. "Melting in the deep upper mantle oceanward of the Honshu slab." Physics of the Earth and Planetary Interiors 175, no. 3-4 (July 2009): 137–44. http://dx.doi.org/10.1016/j.pepi.2009.03.007.

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12

Gorbachev, N. S., A. V. Kostyuk, A. N. Nekrasov, P. N. Gorbachev, and D. M. Soultanov. "Experimental study of the system peridotite–basalt–fluid: phase relations at supra- and sepercritical P-T parameters." Петрология 27, no. 6 (December 16, 2019): 606–16. http://dx.doi.org/10.31857/s0869-5903276606-616.

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To obtain new data on the phase relationships in the fluid-containing upper mantle at P up to 4 GPa, T up to 1400C, partial melting of H2O-containing peridotite, basalt, as well as peridotite-basalt association with an alkaline-carbonate fluid was experimentally studied as a model of the mantle reservoir with protoliths of the subdued oceanic crust. At partial melting of H2O-containing peridotite at P = 3.73.9 GPa, T = 10001300C, critical ratios were observed in the whole studied interval P and T. At partial melting of H2O-containing basalt critical relationships between the silicate melt and the aqueous fluid were observed at T = 1000C, P = 3.7 GPa. At T = 1100C, Na-alkaline silicate melt coexisted with garnetite, at T = 1150 and 1300C with clinopyroxenite. Signs of critical relationships between the carbonated silicate melt and the fluid were observed in peridotite-basalt-alkaline-water-carbonate fluid system at Р = 4 GPa, T = 1400C. The reaction ratios among the minerals of peritotite restite with the substitutions of Ol Opx Ca-Cpx K-Amf indicated a high chemical activity of the supercritical fluid melt. The results of the experiments suggest that in the fluid-containing upper mantle with supercritical Р-Т there are areas of partial melting (asthenosphere lenses), containing near-solidus supercritical fluid-melts enriched with incompatible elements, with high reactivity. Mantle reservoirs with supercritical fluid-melts, similar in geochemical terms to the enriched mantle, can serve as a source of magma enriched with incompatible elements. The modal and latent metasomatism of the upper mantle under the influence of supercritical fluid-melts leads to the peridotite refertilization due to the enrichment of restite minerals with incompatible elements and its eclogitization.

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13

Yaxley, Gregory M., Bruce A. Kjarsgaard, and A. Lynton Jaques. "Evolution of Carbonatite Magmas in the Upper Mantle and Crust." Elements 17, no. 5 (October 1, 2021): 315–20. http://dx.doi.org/10.2138/gselements.17.5.315.

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Carbonatites are the most silica-poor magmas known and are amongst Earth’s most enigmatic igneous rocks. They crystallise to rocks dominated by the carbonate minerals calcite and dolomite. We review models for carbonatite petrogenesis, including direct partial melting of mantle lithologies, exsolution from silica-undersaturated alkali silicate melts, or direct fractionation of carbonated silicate melts to carbonate-rich residual melts. We also briefly discuss carbonatite–mantle wall-rock reactions and other processes at mid-to upper crustal depths, including fenitisation, overprinting by carbohydrothermal fluids, and reaction between carbonatite melt and crustal lithologies.

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14

He, Chuansong, and M. Santosh. "Mantle roots of the Emeishan plume: an evaluation based on teleseismic P-wave tomography." Solid Earth 8, no. 6 (November 3, 2017): 1141–51. http://dx.doi.org/10.5194/se-8-1141-2017.

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Abstract. The voluminous magmatism associated with large igneous provinces (LIPs) is commonly correlated to upwelling plumes from the core–mantle boundary (CMB). Here we analyse seismic tomographic data from the Emeishan LIP in southwestern China. Our results reveal vestiges of delaminated crustal and/or lithospheric mantle, with an upwelling in the upper mantle beneath the Emeishan LIP rather than a plume rooted in the CMB. We suggest that the magmatism and the Emeishan LIP formation might be connected with the melting of delaminated lower crustal and/or lithospheric components which resulted in plume-like upwelling from the upper mantle or from the mantle transition zone.

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15

Rogkala, Aikaterini, Petros Petrounias, Basilios Tsikouras, Panagiota Giannakopoulou, and Konstantin Hatzipanagiotou. "Mineralogical Evidence for Partial Melting and Melt-Rock Interaction Processes in the Mantle Peridotites of Edessa Ophiolite (North Greece)." Minerals 9, no. 2 (February 17, 2019): 120. http://dx.doi.org/10.3390/min9020120.

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The Edessa ophiolite complex of northern Greece consists of remnants of oceanic lithosphere emplaced during the Upper Jurassic-Lower Cretaceous onto the Palaeozoic-Mesozoic continental margin of Eurasia. This study presents new data on mineral compositions of mantle peridotites from this ophiolite, especially serpentinised harzburgite and minor lherzolite. Lherzolite formed by low to moderate degrees of partial melting and subsequent melt-rock reaction in an oceanic spreading setting. On the other hand, refractory harzburgite formed by high degrees of partial melting in a supra-subduction zone (SSZ) setting. These SSZ mantle peridotites contain Cr-rich spinel residual after partial melting of more fertile (abyssal) lherzolite with Al-rich spinel. Chromite with Cr# > 60 in harzburgite resulted from chemical modification of residual Cr-spinel and, along with the presence of euhedral chromite, is indicative of late melt-peridotite interaction in the mantle wedge. Mineral compositions suggest that the Edessa oceanic mantle evolved from a typical mid-ocean ridge (MOR) oceanic basin to the mantle wedge of a SSZ. This scenario explains the higher degrees of partial melting recorded in harzburgite, as well as the overprint of primary mineralogical characteristics in the Edessa peridotites.

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16

Lunev, B. V., and V. V. Lapkovsky. "MODEL OF DECOMPRESSION MELTING MECHANISM IN CONVECTIVE-UNSTABLE THERMAL LITHOSPHERE (FIRST APPROXIMATION)." Geodynamics & Tectonophysics 12, no. 3 (September 17, 2021): 485–98. http://dx.doi.org/10.5800/gt-2021-12-3-0535.

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We propose a model of decompression melting, separation, migration and freezing of the melt in the upper mantle during the convective instability process. The model takes into account differences between phase diagrams of the melt and the matrix and the resultant features of the melt’s behavior, without calculating reaction rates in a multicomponent medium. It is constructed under an explicit concept of the local thermodynamic equilibrium of the existing phases. Therefore, we further develop the first approximation of the descriptions of convection in the upper mantle and the formation of large epicontinental sedimentary basins, which have been presented in earlier publications. Our computational experiments show that primary melting of the upper mantle’s fertile material occurs intensively in a narrow frontal part of the ascending hot material flow. Then, the depleted and partially melted material rises farther upward from the front of primary melting. Melting of the depleted material continues at lower pressures in a rather wide range of depths (120–77 km). Further, the migrating melt is supplied by two sources, i.e. a deep-seated one, wherein the fertile material melts, and the medium-depth one, wherein melting of the depleted material takes place. Once the temperature and pressure rates of the melt reach the values corresponding to those of its solidus, a narrow freezing front is formed. Its width is almost similar to the primary melting front. As the ascending convective flow develops, the freezing front shifts upward. As a result, a quite thick (around 40–50 km) basalt-saturated layer occurs above the freezing front. An important observation in our modeling experiments is that, despite a considerably large total volume of the melted material, a one-time melt content in the mantle does not exceed tenths of one percent, when we consider averaging to volumes with a linear size of about 1.0 km. The basalt melt extraction depletes iron in the mantle and significantly reduces the mantle density. Considering the calculated basalt-depletion values for the matrix at 0.1–0.2, the density deficit doubles in comparison to the thermal expansion of the material. Logically, both the Rayleigh number and the intensity of convection also double (and this is confirmed by the calculations), which means that convection is enhanced after the melting start.Testing of the model shows that it gives a reasonable picture that is consistent with the available geological and geophysical data on the structure of the lithosphere underneath the currently developing epicontinental sedimentary basins. Furthermore, within the limits of its detail, this model is consistent with the results of modeling experiments focused on melting and melting dynamics, which are based on calculations of reactions between components of the mantle material.

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17

Rasha Houssam Khaddam, Rasha Houssam Khaddam. "A proposed model for Mantle upwelling in the Syrian coastal: نموذج مقترح لتقبب المعطف في الساحل السوري." Journal of natural sciences, life and applied sciences 5, no. 4 (December 27, 2021): 46–33. http://dx.doi.org/10.26389/ajsrp.s090821.

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The aim of the research is to develop a conception of the proposed model for Mantle upwelling (diapering) in the coastal region, as the results of this research showed the occurrence of Mantle upwelling regression under the coastal region during the Pliocene period, and this led to the occurrence of basaltic deposits in the Syrian coast during the Pliocene, where we note the center of the vaulting was under Qardaha and Safita, and the Mantle upwelling reached a depth of 35 km within the continental crust, where basalt rocks were formed as a result of partial melting of the upper mantle, and it is upwelled with low melting and differential degrees. Basalt rocks in the initial differential phase of the original basaltic silage.

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18

Wang, Ze-Zhou, Sheng-Ao Liu, Jingao Liu, Jian Huang, Yan Xiao, Zhu-Yin Chu, Xin-Miao Zhao, and Limei Tang. "Zinc isotope fractionation during mantle melting and constraints on the Zn isotope composition of Earth’s upper mantle." Geochimica et Cosmochimica Acta 198 (February 2017): 151–67. http://dx.doi.org/10.1016/j.gca.2016.11.014.

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19

Zhuang, Yukai, Junwei Li, Wenhua Lu, Xueping Yang, Zhixue Du, and Qingyang Hu. "High Temperature Melting Curve of Basaltic Glass by Laser Flash Heating." Chinese Physics Letters 39, no. 2 (February 1, 2022): 020701. http://dx.doi.org/10.1088/0256-307x/39/2/020701.

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Basalt is an igneous rock originating from the cooling and solidification of magma and covers approximately 70% of Earth’s surface. Basaltic glass melting in the deep Earth is a fundamental subject of research for understanding geophysics, geochemistry, and geodynamic processes. In this study, we design a laser flash heating system using two-dimensional, four-color multi-wavelength imaging radiometry to measure the basaltic glass melting temperature under high pressure conditions in diamond anvil cells. Our experiment not only determines the temperature at the center of heating but also constructs a temperature distribution map for the surface heating area, and enables us to assess the temperature gradient. Through precise temperature measurements, we observe that the basaltic glass melting temperature is higher than those in previous reports, which is near the normal upper-mantle isotherm, approaching the hot geotherm. This suggests that basalt should not melt in most of the normal upper mantle and the basaltic melts could exist in some hot regions.

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20

Chen, Ling, Limei Tang, Xiaohu Li, Jie Zhang, Wei Wang, Zhenggang Li, Hao Wang, Xichang Wu, and Fengyou Chu. "Ancient Melt Depletion and Metasomatic History of the Subduction Zone Mantle: Osmium Isotope Evidence of Peridotites from the Yap Trench, Western Pacific." Minerals 9, no. 12 (November 20, 2019): 717. http://dx.doi.org/10.3390/min9120717.

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Highly depleted peridotites from the Yap Trench in the western Pacific Ocean have been studied for Re-Os elements and Re-Os isotopes. These peridotites have a low Re-Os content and variable 187Os/188Os ratios (0.12043–0.14867). The highest 187Os/188Os ratio is far higher than that of the primitive upper mantle and the lowest 187Os/188Os ratio is comparable to the most unradiogenic 187Os/188Os ratio (0.11933) discovered in subduction zone peridotites. The suprachondritic 187Os/188Os ratios of the Yap Trench peridotites results from modification of the mantle wedge by slab-derived fluid and melt. This is consistent with the observation that high 187Os/188Os ratios generally occur in oceanic peridotites with low Os content (<2 ppb) since Os may be reduced during late processes such as fluid alteration and melt refertilization. The sub-chondritic 187Os/188Os ratios of the Yap Trench peridotites correspond to a Re depletion age of 0.24–1.16 billion years, which means that these peridotites represent old mantle residue of ancient melting events. This ancient melting, combined with probable back-arc melting and forearc melting during subduction initiation, indicates that the Yap Trench mantle has a complex evolutionary history. The amount of old mantle residue in the oceanic asthenosphere was underestimated because the 187Os/188Os ratio in mantle peridotites is elevated during late processes. Therefore, old depleted mantle fragments may contribute substantially to the chemical heterogeneity of the oceanic mantle.

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21

Sharkov, E. V., A. V. Chistyakov, M. M. Bogina, O. A. Bogatikov, V. V. Shchiptsov, B. V. Belyatsky, and P. V. Frolov. "Ultramafic-alkaline-carbonatite complexes as a result of two-stage melting of mantle plume: evidence from the mid-paleoproterozoic Tiksheozero intrusion, Northern Karelia, Russia." Доклады Академии наук 486, no. 4 (June 10, 2019): 460–65. http://dx.doi.org/10.31857/s0869-56524864460-465.

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Tiksheozero ultramafic-alkaline-carbonatite intrusive complex, like numerous carbonatite-bearing complexes of similar composition, is a part of large igneous province, related to the ascent of thermochemical mantle plume. Our geochemical and isotopic data evidence that ultramafites and alkaline rocks are joined by fractional crystallization, whereas carbonatitic magmas has independent origin. We suggest that origin of parental magmas of the Tiksheozero complex, as well as other ultramafic-alkaline-carbonatite complexes, was provided by two-stage melting of the mantle-plume head: 1) adiabatic melting of its inner part, which produced moderately-alkaline picrites, which fractional crystallization led to appearance of alkaline magmas, and 2) incongruent melting of the upper cooled margin of the plume head under the influence of CO2-rich fluids that arrived from underlying zone of adiabatic melting gave rise to carbonatite magmas.

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22

Abbaspour Shirjoposht, Leila, Sayed Jamal al-Din Sheikh Zakariaee, Mohammad Reza Ansari, and Mohammad Hashem Emami. "Geochemistry of mid- upper eocene intra-continental alkaline volcanic range, south part of central alborz mountains, north of Iran." Nexo Revista Científica 33, no. 02 (December 31, 2020): 511–24. http://dx.doi.org/10.5377/nexo.v33i02.10788.

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The Ziaran volcanic Belt (ZVB), North of Iran contains a number of intra-continental alkaline volcanic range situated on South part of central Alborz Mountains, formed along the localized extensional basins developed in relation with the compressional regime of Eocene. The mid-upper Eocene volcanic suite comprises the extracted melt products of adiabatic decompression melting of the mantle that are represented by small volume intra-continental plate volcanic rocks of alkaline volcanism and their evaluated Rocks with compositions representative of mantle-derived, primary (or near-primary) melts. Trace element patterns with significant enrichment in LILE, HFSE and REEs, relative to Primitive Mantle. Chondrite-normalized of rare earth elements and enrichment in incompatible elements and their element ratios (e. g. LREE/HREE, MREE/HREE, LREE/MREE) shown these element modelling indicates that the magmas were generated by comparably variable degrees of partial melting of garnet lherzolite and a heterogeneous asthenospheric, OIB mantle sources.

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23

Walter, Michael J., Thomas W. Sisson, and Dean C. Presnall. "A mass proportion method for calculating melting reactions and application to melting of model upper mantle lherzolite." Earth and Planetary Science Letters 135, no. 1-4 (October 1995): 77–90. http://dx.doi.org/10.1016/0012-821x(95)00148-6.

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24

Fryer, Brian J., and John D. Greenough. "Evidence for mantle heterogeneity from platinum-group-element abundances in Indian Ocean basalts." Canadian Journal of Earth Sciences 29, no. 11 (November 1, 1992): 2329–40. http://dx.doi.org/10.1139/e92-181.

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Oceanic-island tholeiitic basalts recovered from four sunken oceanic islands along the Reunion hot-spot trace show trace-element and mineralogical characteristics ranging from typical oceanic-island tholeiites to incompatible-element-depleted tholeiites resembling mid-ocean-ridge basalts. There are also variable degrees of magma evolution at each island. Noble metal (Au, Pd, Pt, Rh, Ru, Ir) abundances tend to decrease with magma evolution and with magma "alkalinity", indicating that the metals behave as compatible elements during crystal fractionation processes and during mantle melting processes. Palladium-to-iridium ratios also decrease with increasing alkalinity. Absolute abundances of elements such as Pd are higher than those in typical mid-ocean-ridge basalts, by factors up to 30, despite many major-element similarities with the latter. Comparison with other types of mafic rocks shows that Pd/Ir ratios increase with decreasing alkalinity in basaltic rocks but plunge to alkali-basalt values in komatiites. A model involving retention of low-melting-point Au, Pd, and Rh in mantle sulphides, which completely dissolve by intermediate percentages of melting, and the high-melting-point metals Ir and Ru in late-melting mantle alloys explains increasing Pd/Ir ratios with decreasing alkalinity (increasing melting percentages) in oceanic basalts and the low Pd/Ir ratios of high-percentage melt komatiites.The high noble metal concentrations in Indian Ocean basalts compared with basalts from many other ocean basins are most easily explained by higher concentrations in their source regions. This may be related to incomplete mixing of a post-core-formation meteoritic component of the upper mantle, or deep mantle plume-derived blebs of core material that either failed to reach the core, during core–mantle differentiation, or were plucked from the core by a convecting lower mantle. The latter is tentatively favoured due to the apparently higher noble metal concentrations in oceanic-island (plume) basalts.

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25

Rollinson, Hugh. "No plate tectonics necessary to explain Eoarchean rocks at Isua (Greenland)." Geology 50, no. 2 (October 20, 2021): 147–51. http://dx.doi.org/10.1130/g49278.1.

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Abstract Trace element and isotopic data for basalts from the Isua greenstone belt, West Greenland, indicate that they were derived from a range of mantle reservoirs that included depleted lower mantle, the mantle transition zone, and a primitive mantle reservoir probably located in the shallow upper mantle. Modeling of trace element compositions indicates that the Isua basalts were formed through the mixing between and refertilization of these diverse sources and their resultant melts and that this took place in the shallow upper mantle. It is proposed that the melting and mixing were driven by the heat transferred from hot deep mantle sources. This geochemical interpretation leads to a geodynamic model in which deep mantle domains rise to melt in the shallow mantle where there is mixing between a range of sources and melts. There is no evidence for material descending from the shallow to deeper mantle and no necessity for the involvement of crustal materials. These processes imply the activity of a mantle plume and/or heat pipe.

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26

Kadik, A. A., and O. A. Lukanin. "PATHS OF MANTLE OUTGASSING DURING MELTING: THE ROLE OF PARTIAL MELTING OF UPPER MANTLE ROCKS IN THE EVOLUTION OF FLUID COMPOSITION AND REDOX REGIME." International Geology Review 27, no. 5 (May 1985): 563–72. http://dx.doi.org/10.1080/00206818509466444.

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27

Vlastélic, I., H. Bougault, and L. Dosso. "Heterogeneous heat production in the Earth’s upper mantle: blob melting and MORB composition." Earth and Planetary Science Letters 199, no. 1-2 (May 2002): 157–72. http://dx.doi.org/10.1016/s0012-821x(02)00538-1.

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28

Vander Auwera, Jacqueline, Olivier Namur, Adeline Dutrieux, Camilla Maya Wilkinson, Morgan Ganerød, Valentin Coumont, and Olivier Bolle. "Mantle Melting and Magmatic Processes Under La Picada Stratovolcano (CSVZ, Chile)." Journal of Petrology 60, no. 5 (April 1, 2019): 907–44. http://dx.doi.org/10.1093/petrology/egz020.

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Abstract Where and how arc magmas are generated and differentiated are still debated and these questions are investigated in the context of part of the Andean arc (Chilean Southern Volcanic Zone) where the continental crust is thin. Results are presented for the La Picada stratovolcano (41°S) that belongs to the Central Southern Volcanic Zone (CSVZ) (38°S–41·5°S, Chile) which results from the subduction of the Nazca plate beneath the western margin of the South American continent. Forty-seven representative samples collected from different units of the volcano define a differentiation trend from basalt to basaltic andesite and dacite (50·9 to 65·6 wt % SiO2). This trend straddles the tholeiitic and calc-alkaline fields and displays a conspicuous compositional Daly Gap between 57·0 and 62·7 wt % SiO2. Interstitial, mostly dacitic, glass pockets extend the trend to 76·0 wt % SiO2. Mineral compositions and geochemical data indicate that differentiation from the basaltic parent magmas to the dacites occurred in the upper crust (∼0·2 GPa) with no sign of an intermediate fractionation stage in the lower crust. However, we have currently no precise constraint on the depth of differentiation from the primary magmas to the basaltic parent magmas. Stalling of the basaltic parent magmas in the upper crust could have been controlled by the occurrence of a major crustal discontinuity, by vapor saturation that induced volatile exsolution resulting in an increase of melt viscosity, or by both processes acting concomitantly. The observed Daly Gap thus results from upper crustal magmatic processes. Samples from both sides of the Daly Gap show contrasting textures: basalts and basaltic andesites, found as lavas, are rich in macrocrysts, whereas dacites, only observed in crosscutting dykes, are very poor in macrocrysts. Moreover, modelling of the fractional crystallization process indicates a total fractionation of 43% to reach the most evolved basaltic andesites. The Daly Gap is thus interpreted as resulting from critical crystallinity that was reached in the basaltic andesites within the main storage region, precluding eruption of more evolved lavas. Some interstitial dacitic melt was extracted from the crystal mush and emplaced as dykes, possibly connected to small dacitic domes, now eroded away. In addition to the overall differentiation trend, the basalts to basaltic andesites display variable MgO, Cr and Ni contents at a given SiO2. Crystal accumulation and high pressure fractionation fail to predict this geochemical variability which is interpreted as resulting from variable extents of fractional crystallization. Geothermobarometry using recalculated primary magmas indicates last equilibration at about 1·3–1·5 GPa and at a temperature higher than the anhydrous peridotite solidus, pointing to a potential role of decompression melting. However, because the basalts are enriched in slab components and H2O compared to N-MORB, wet melting is highly likely.

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Sieber, Melanie J., Max Wilke, Oona Appelt, Marcus Oelze, and Monika Koch-Müller. "Melting relations of Ca–Mg carbonates and trace element signature of carbonate melts up to 9 GPa – a proxy for melting of carbonated mantle lithologies." European Journal of Mineralogy 34, no. 5 (October 6, 2022): 411–24. http://dx.doi.org/10.5194/ejm-34-411-2022.

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Abstract. The most profound consequences of the presence of Ca–Mg carbonates (CaCO3–MgCO3) in the Earth's upper mantle may be to lower the melting temperatures of the mantle and control the melt composition. Low-degree partial melting of a carbonate-bearing mantle produces CO2-rich, silica-poor melts compositionally imposed by the melting relations of carbonates. Thus, understanding the melting relations in the CaCO3–MgCO3 system facilitates the interpretation of natural carbonate-bearing silicate systems. We report the melting relations of the CaCO3–MgCO3 system and the partition coefficient of trace elements between carbonates and carbonate melt from experiments at high pressure (6 and 9 GPa) and temperature (1300–1800 ∘C) using a rocking multi-anvil press. In the absence of water, Ca–Mg carbonates are stable along geothermal gradients typical of subducting slabs. Ca–Mg carbonates (∼ Mg0.1–0.9Ca0.9–0.1CO3) partially melt beneath mid-ocean ridges and in plume settings. Ca–Mg carbonates melt incongruently, forming periclase crystals and carbonate melt between 4 and 9 GPa. Furthermore, we show that the rare earth element (REE) signature of Group-I kimberlites, namely strong REE fractionation and depletion of heavy REE relative to the primitive mantle, is resembled by carbonate melt in equilibrium with Ca-bearing magnesite and periclase at 6 and 9 GPa. This suggests that the dolomite–magnesite join of the CaCO3–MgCO3 system might be useful to approximate the REE signature of carbonate-rich melts parental to kimberlites.

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Andronikov, Alexandre V., Irina E. Andronikova, and Tamara Sidorinova. "Trace-Element Geochemistry of Sulfides in Upper Mantle Lherzolite Xenoliths from East Antarctica." Minerals 11, no. 7 (July 16, 2021): 773. http://dx.doi.org/10.3390/min11070773.

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Sulfides in upper mantle lherzolite xenoliths from Cretaceous alkaline-ultramafic rocks in the Jetty Peninsula (East Antarctica) were studied for their major and trace-element compositions using SEM and LA-ICP-MS applied in situ. Modal abundance of sulfides is the lowest in Cpx-poor lherzolites ≤ Spl-Grt lherzolites << Cpx-rich lherzolites. Most sulfides are either interstitial (i-type) or inclusions in rock-forming minerals (e-type) with minor sulfide phases mostly present in metasomatic veinlets and carbonate-silicate interstitial patches (m-type). The main sulfide assemblage is pentlandite + chalcopyrite ± pyrrhotite; minor sulfides are polydymite, millerite, violarite, siegenite, and monosulfide solution (mss). Sulfide assemblages in the xenolith matrix are a product of the subsolidus re-equilibration of primary mss at temperatures below ≤300 °C. Platinum group elements (PGE) abundances suggest that most e-type sulfides are the residues of melting processes and that the i-type sulfides are crystallization products of sulfide-bearing fluids/liquids. The m-type sulfides might have resulted from low-temperature metasomatism by percolating sulfide-carbonate-silicate fluids/melts. The PGE in sulfide record processes are related to partial melting in mantle and intramantle melt migration. Most other trace elements initially partitioned into interstitial sulfide liquid and later metasomatically re-enriched residual sulfides overprinting their primary signatures. The extent of element partitioning into sulfide liquids depends on P, T, fO2, and host peridotite composition.

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31

Chen, Chen, Ben-Xun Su, Christina Yan Wang, İbrahim Uysal, and Zhuo-Sen Yao. "Mantle melting models of the Kızıldağ ophiolite in SE Turkey: Two types of partial melting processes in the oceanic upper mantle of southern Neo-Tethys." Lithos 398-399 (October 2021): 106348. http://dx.doi.org/10.1016/j.lithos.2021.106348.

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32

Shragge, J., M. G. Bostock, C. G. Bank, and R. M. Ellis. "Integrated teleseismic studies of the southern Alberta upper mantle." Canadian Journal of Earth Sciences 39, no. 3 (March 1, 2002): 399–411. http://dx.doi.org/10.1139/e01-084.

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This paper presents results from a teleseismic experiment conducted across the Hearne Province in south-central Alberta. Data from an array of nine portable broad-band seismographs deployed along a 500 km NWSE array have been supplemented with recordings from two Canadian National Seismograph Network stations. P-wave delay times from 293 earthquakes have been inverted for upper-mantle velocity structure below the array. The recovered model reveals high velocities beneath much of the southern Hearne Province to depths of 200250 km, which are interpreted as deep-seated lithospheric structure. Contrary to recent tectonic models, these results suggest that the Hearne lithosphere has remained intact. In particular, it appears unlikely that evidence for extensive, lower crustal melting derives from lithospheric delamination. However, the results admit the possibility that high mantle conductivity, as revealed in magnetotelluric studies, originates through small volumes of connected hydrous minerals or other conductive species introduced during subduction. Decreased upper-mantle velocities at the northern end of the Medicine Hat block also pose challenges for the interpretation of differential subsidence across the region which may manifest distant forcing due to more recent subduction. Multievent SKS-splitting analysis yields an average polarization direction that is broadly consistent with both the orientation of fossil strain fields, related to ~ 1.8 Ga NWSE shortening, and North American absolute plate motion. Moho depth estimates from receiver functions are fairly uniform (~ 38 km) beneath northern stations but show crustal thickening (>40 km) within the Medicine Hat block to the south and are consistent with values from active-source profiling.

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33

Cobden, Laura, Jeannot Trampert, and Andreas Fichtner. "Insights on Upper Mantle Melting, Rheology, and Anelastic Behavior From Seismic Shear Wave Tomography." Geochemistry, Geophysics, Geosystems 19, no. 10 (October 2018): 3892–916. http://dx.doi.org/10.1029/2017gc007370.

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34

Xu, Y. G., M. Sun, W. Yan, Y. Liu, X. L. Huang, and X. M. Chen. "Xenolith evidence for polybaric melting and stratification of the upper mantle beneath South China." Journal of Asian Earth Sciences 20, no. 8 (November 2002): 937–54. http://dx.doi.org/10.1016/s1367-9120(01)00087-6.

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35

Ottolini, Luisa, Didier Laporte, Nicola Raffone, Jean-Luc Devidal, and Brieuc Le Fèvre. "New experimental determination of Li and B partition coefficients during upper mantle partial melting." Contributions to Mineralogy and Petrology 157, no. 3 (September 12, 2008): 313–25. http://dx.doi.org/10.1007/s00410-008-0336-7.

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36

Ni, Huaiwei, Hans Keppler, and Harald Behrens. "Electrical conductivity of hydrous basaltic melts: implications for partial melting in the upper mantle." Contributions to Mineralogy and Petrology 162, no. 3 (February 24, 2011): 637–50. http://dx.doi.org/10.1007/s00410-011-0617-4.

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37

HAURI, E., G. GAETANI, and T. GREEN. "Partitioning of water during melting of the Earth's upper mantle at H2O-undersaturated conditions." Earth and Planetary Science Letters 248, no. 3-4 (August 30, 2006): 715–34. http://dx.doi.org/10.1016/j.epsl.2006.06.014.

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38

Furnes, Harald, Harald Brekke, Jan Nordås, and Jan Hertogen. "Lower Palaeozoic convergent plate margin volcanism on Bømlo, southwest Norwegian Caledonides: geochemistry and petrogenesis." Geological Magazine 123, no. 2 (March 1986): 123–42. http://dx.doi.org/10.1017/s0016756800029782.

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AbstractMajor and trace element analyses of a Lower Palaeozoic metavolcanic sequence of convergent plate type from Bømlo, southwest Norwegian Caledonides, are presented and discussed. This sequence ranges in age from the Upper Cambrian through the Lower Silurian. Petrogenetic models for the lavas in terms of partial melting and crystal fractionation are discussed. Two models are presented for the metabasalts in order to explain their different trace element abundances and ratios:(1) REE modelling, assuming a mantle source with REE abundances twice chondritic, suggests progressively more varied sources with time. Thus the metabasalts from the oldest (Upper Cambrian–Lower Ordovician) Geitung Unit of primitive island arc type, and those of the mid-Ordovician Siggjo Complex of ‘Basin and Range’ type can be modelled in terms of high (around 25%) and moderate (around 5%) degrees of partial melting of spinel lherzolite, respectively. The metabasalts of the post-Ashgillian Vikafjord Group of typical continental flood basalts are compatible with moderate (c. 5–10%) degrees of partial melting of spinel- and garnet-lherzolite sources. The supposed Lower Silurian Langevåg Group of calc-alkaline ‘Andean’ type metabasalts, grading into alkaline to tholeiitic metabasalts of early marginal basin (youngest) character, require low (<5%) to moderate degrees of partial melting of amphibole-, garnet- and spinel-lherzolite sources, respectively.(2) Source heterogeneity, produced by subduction zone-derived enrichment of LIL elements, and contemporaneous stabilization of minor phases which accommodate HFS elements. This process, combined with possible continental contamination, may possibly yield the trace element concentrations and ratios of the different metabasalts by partial melting of modally similar mantle sources.

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39

Xu, Yan, Jun Xu, and Wen Hu Zhang. "Sea Bottom EM Field of M2 Tidal to Probe Upper Mantle Conductivity." Advanced Materials Research 683 (April 2013): 828–31. http://dx.doi.org/10.4028/www.scientific.net/amr.683.828.

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Recent laboratory experiments demonstrate that electrical conductivity of upper mantle (UM) minerals is greatly increased by small amounts of water or by partial melt. Determination of deep conductivity using electromagnetic (EM) methods can thus provide constraints on the presence of volatiles and melting processes in UM. Probing conductivity at UM depths requires EM data with periods of a few to one cycle per day. This is a challenging period range for EM studies due to the spatially complex ionospheric source that dominates at these periods. The idea of exploiting tidal signals for EM studies of the Earth is not new, but so far it was used only for interpretation of inland and transoceanic electric field data due to M2. Emphasis in this work is made on a discussion of sea bottom magnetic field of the same origin.

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40

Zhao, Xinyun, Libo Hao, Qiaoqiao Wei, Qingqing Liu, Jian Zhou, Xueqiu Wang, Jilong Lu, Yuyan Zhao, and Chengyou Ma. "Origin of Late Triassic mafic–ultramafic intrusions in the Hongqiling Ni–Cu sulfide deposit, Northeast China: evidence from trace element and Sr–Nd isotope geochemistry." Canadian Journal of Earth Sciences 55, no. 12 (December 2018): 1312–23. http://dx.doi.org/10.1139/cjes-2018-0041.

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There are many Late Triassic mafic–ultramafic intrusions in the Hongqiling magmatic Ni–Cu sulfide deposit, Northeast China. Research on magma evolution leading to formation of these mafic–ultramafic intrusions is of great significance for understanding the mantle beneath Northeast China and associated Ni–Cu mineralization. A trace element study of the No. 1, 3, and 7 intrusions in the Hongqiling deposit reveals that these mafic–ultramafic intrusions are characterized by enrichment of incompatible elements, which however cannot be interpreted by subduction modification. Furthermore, model of batch partial melting of depleted mantle accompanied by upper crustal contamination can simulate the trace element patterns of these mafic–ultramafic intrusions, but partial melting of depleted mantle accompanied by lower crustal contamination model cannot work. In addition, Sr–Nd isotopic compositions of the Hongqiling No. 1, 3, and 7 intrusions also indicate that crustal contamination could have occurred mainly during the magma ascent. Consequently, a possible scenario for the magma evolution is that the primary mafic–ultramafic magma was derived from batch partial melting of a depleted mantle, and then contaminated by Cambrian–Ordovician metamorphic rocks of the Hulan Group during ascent. We conclude that the mantle source contained no significant crustal component in the Late Triassic and was also independent of substantial contribution from subducted material, and therefore the Mesozoic large-scale lithospheric delamination beneath eastern China may happen after a period of time of the Late Triassic.

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41

Tikoo, Sonia M., and Linda T. Elkins-Tanton. "The fate of water within Earth and super-Earths and implications for plate tectonics." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375, no. 2094 (April 17, 2017): 20150394. http://dx.doi.org/10.1098/rsta.2015.0394.

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The Earth is likely to have acquired most of its water during accretion. Internal heat of planetesimals by short-lived radioisotopes would have caused some water loss, but impacts into planetesimals were insufficiently energetic to produce further drying. Water is thought to be critical for the development of plate tectonics, because it lowers viscosities in the asthenosphere, enabling subduction. The following issue persists: if water is necessary for plate tectonics, but subduction itself hydrates the upper mantle, how is the upper mantle initially hydrated? The giant impacts of late accretion created magma lakes and oceans, which degassed during solidification to produce a heavy atmosphere. However, some water would have remained in the mantle, trapped within crystallographic defects in nominally anhydrous minerals. In this paper, we present models demonstrating that processes associated with magma ocean solidification and overturn may segregate sufficient quantities of water within the upper mantle to induce partial melting and produce a damp asthenosphere, thereby facilitating plate tectonics and, in turn, the habitability of Earth-like extrasolar planets. This article is part of the themed issue ‘The origin, history and role of water in the evolution of the inner Solar System’.

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42

Dupuy, C., J. Dostal, and J. L. Bodinier. "Geochemistry of spinel peridotite inclusions in basalts from Sardinia." Mineralogical Magazine 51, no. 362 (October 1987): 561–68. http://dx.doi.org/10.1180/minmag.1987.051.362.10.

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AbstractThe spinel peridotite inclusions in basalts from Sardinia are upper-mantle residues affected by metasomatism which led to an enrichment particularly of U and light REE. The metasomatism took place prior to the recrystallization which produced the primary mineral assemblage of the inclusions. The compositional variations imply that the xenoliths are residual after at least two melting events.

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43

Ailow, Y., S. V. Rasskazov, T. A. Yasnygina, I. S. Chuvashova, Zhenhua Xie, and Yi-min Sun. "Basalts of the Bystraya zone from sources of sub-continental lithospheric mantle: the Tunka valley of the Baikal Rift System." Geology and Environment 1, no. 1 (2021): 41–58. http://dx.doi.org/10.26516/2541-9641.2021.1.41.

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In terms of petrochemical and trace-element data, basalts from the axial rift valley are suggested to originate from sources of the sub-continental lithospheric mantle, inhomogeneity of which was due to extracting upper and lower crustal components. Trace-element modeling indicated 3-8 %partial melting of apatite-bearing sources with varying garnet and clinopyroxene proportions.

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44

Safonov, O. G., V. G. Butvina, E. V. Limanov, and S. A. Kosova. "Mineral indicators of reactions involving fluid salt components in the deep lithosphere." Петрология 27, no. 5 (August 18, 2019): 525–56. http://dx.doi.org/10.31857/s0869-5903275525-556.

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The salt components of H2O and H2O–CO2 fluids are very important agents of metasomatism and partial melting of crustal and mantle rocks. The paper presents examples and synthesized data on mineral associations in granulite- and amphibolite-facies rocks of various composition in the middle and lower crust and in upper-mantle eclogites and peridotites that provide evidence of reactions involving salt components of fluids. These data are analyzed together with results of model experiments that reproduce some of these associations and make it possible to more accurately determine their crystallization parameters.

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45

Johnson, Kevin T. M., Henry J. B. Dick, and Nobumichi Shimizu. "Melting in the oceanic upper mantle: An ion microprobe study of diopsides in abyssal peridotites." Journal of Geophysical Research 95, B3 (1990): 2661. http://dx.doi.org/10.1029/jb095ib03p02661.

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46

DAWSON, J. B. "Metasomatism and Partial Melting in Upper-Mantle Peridotite Xenoliths from the Lashaine Volcano, Northern Tanzania." Journal of Petrology 43, no. 9 (September 1, 2002): 1749–77. http://dx.doi.org/10.1093/petrology/43.9.1749.

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47

Scarfe, Christopher M., and Eiichi Takahashi. "Melting of garnet peridotite to 13 GPa and the early history of the upper mantle." Nature 322, no. 6077 (July 1986): 354–56. http://dx.doi.org/10.1038/322354a0.

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48

Ozawa, Kazuhito, and Nobumichi Shimizu. "Open-system melting in the upper mantle: Constraints from the Hayachine-Miyamori ophiolite, northeastern Japan." Journal of Geophysical Research: Solid Earth 100, B11 (November 10, 1995): 22315–35. http://dx.doi.org/10.1029/95jb01967.

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49

Laporte, Didier, Sarah Lambart, Pierre Schiano, and Luisa Ottolini. "Experimental derivation of nepheline syenite and phonolite liquids by partial melting of upper mantle peridotites." Earth and Planetary Science Letters 404 (October 2014): 319–31. http://dx.doi.org/10.1016/j.epsl.2014.08.002.

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50

Courtier, Anna M., and Justin Revenaugh. "Deep upper-mantle melting beneath the Tasman and Coral Seas detected with multiple ScS reverberations." Earth and Planetary Science Letters 259, no. 1-2 (July 2007): 66–76. http://dx.doi.org/10.1016/j.epsl.2007.04.027.

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