Journal articles: 'Mantle depletion'

1

Stracke, Andreas. "Tracking mantle depletion." Nature Geoscience 1, no. 4 (April 2008): 215–16. http://dx.doi.org/10.1038/ngeo163.

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Liou, Peng, Jinghui Guo, Ross N. Mitchell, Christopher J. Spencer, Xianhua Li, Mingguo Zhai, Noreen J. Evans, Yanguang Li, Bradley J. McDonald, and Mengqi Jin. "Zircons underestimate mantle depletion of early Earth." Geochimica et Cosmochimica Acta 317 (January 2022): 538–51. http://dx.doi.org/10.1016/j.gca.2021.11.015.

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Zhang, Youxue, and Ting Gan. "Depletion ages and factors of MORB mantle sources." Earth and Planetary Science Letters 530 (January 2020): 115926. http://dx.doi.org/10.1016/j.epsl.2019.115926.

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Stracke, A., J. E. Snow, E. Hellebrand, A. von der Handt, B. Bourdon, K. Birbaum, and D. Günther. "Abyssal peridotite Hf isotopes identify extreme mantle depletion." Earth and Planetary Science Letters 308, no. 3-4 (August 2011): 359–68. http://dx.doi.org/10.1016/j.epsl.2011.06.012.

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5

Snortum, Eric, James M. D. Day, and Matthew G. Jackson. "Pacific Lithosphere Evolution Inferred from Aitutaki Mantle Xenoliths." Journal of Petrology 60, no. 9 (September 1, 2019): 1753–72. http://dx.doi.org/10.1093/petrology/egz047.

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Abstract Highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, Re), major and trace element abundances, and 187Re–187Os systematics are reported for xenoliths and lavas from Aitutaki (Cook Islands), to investigate the composition of Pacific lithosphere. The xenolith suite comprises spinel-bearing lherzolites, dunite, and harzburgite, along with olivine websterite and pyroxenite. The xenoliths are hosted within nephelinite and alkali basalt volcanic rocks (187Os/188Os ∼0·1363 ± 13; 2SD; ΣHSE = 3–4 ppb). The volcanic host rocks are low-degree (2–5%) partial melts from the garnet stability field and an enriched mantle (EM) source. Pyroxenites have similar HSE abundances and Os isotope compositions (Al2O3 = 5·7–8·3 wt %; ΣHSE = 2–4 ppb; 187Os/187Os = 0·1263–0·1469) to the lavas. The pyroxenite and olivine websterite xenoliths directly formed from—or experienced extensive melt–rock interaction with—melts similar in composition to the volcanic rocks that host the xenoliths. Conversely, the Aitutaki lherzolites, harzburgites and dunites are similar in composition to abyssal peridotites with respect to their 187Os/188Os ratios (0·1264 ± 82), total HSE abundances (ΣHSE = 8–28 ppb) and major element abundances, forsterite contents (Fo89·9±1·2), and estimated extents of melt depletion (<10 to >15%). These peridotites are interpreted to sample relatively shallow Pacific mantle lithosphere that experienced limited melt–rock reaction and melting during ridge processes at ∼90 Ma. A survey of maximum time of rhenium depletion ages of Pacific mantle lithosphere from the Cook (Aitutaki ∼1·5 Ga), Austral (Tubuai’i ∼1·8 Ga), Samoan (Savai’i ∼1·5 Ga) and Hawaiian (Oa’hu ∼2 Ga) island groups shows that Mesoproterozoic to Neoproterozoic depletion ages are preserved in the xenolith suites. The variable timing and extent of mantle depletion preserved by the peridotites is, in some instances, superimposed by extensive and recent melt depletion as well as melt refertilization. Collectively, Pacific Ocean island mantle xenolith suites have similar distributions and variations of 187Os/188Os and HSE abundances to global abyssal peridotites. These observations indicate that Pacific mantle lithosphere is typical of oceanic lithosphere in general, and that this lithosphere is composed of peridotites that have experienced both recent melt depletion at ridges and prior and sometimes extensive melt depletion across several Wilson cycles spanning periods in excess of two billion years.

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CHASE, C., and P. PATCHETT. "Stored mafic/ultramafic crust and early Archean mantle depletion." Earth and Planetary Science Letters 91, no. 1-2 (December 1988): 66–72. http://dx.doi.org/10.1016/0012-821x(88)90151-3.

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Bonadiman, C., M. Coltorti, F. Siena, S. Y. O’Reilly, W. L. Griffin, and N. J. Pearson. "Archean to Proterozoic depletion in Cape Verde lithospheric mantle." Geochimica et Cosmochimica Acta 70, no. 18 (August 2006): A58. http://dx.doi.org/10.1016/j.gca.2006.06.221.

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Kamber, Balz S., and Kenneth D. Collerson. "Role of ‘hidden’ deeply subducted slabs in mantle depletion." Chemical Geology 166, no. 3-4 (May 2000): 241–54. http://dx.doi.org/10.1016/s0009-2541(99)00218-1.

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Ojha, Lujendra, Saman Karimi, Kevin W. Lewis, Suzanne E. Smrekar, and Matt Siegler. "Depletion of Heat Producing Elements in the Martian Mantle." Geophysical Research Letters 46, no. 22 (November 20, 2019): 12756–63. http://dx.doi.org/10.1029/2019gl085234.

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Perry, H. K. Claire, and Alessandro Forte. "Upper mantle thermochemical structure from seismic–geodynamic flow models: constraints from the Lithoprobe initiativeThis article is one of a series of papers published in this Special Issue on the theme Lithoprobe — parameters, processes, and the evolution of a continent." Canadian Journal of Earth Sciences 47, no. 4 (April 2010): 463–84. http://dx.doi.org/10.1139/e10-022.

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High-resolution seismic models of three-dimensional mantle heterogeneity are interpreted in terms of upper mantle thermal and compositional anomalies. These anomalies produce density perturbations that drive mantle flow and corresponding convection-related geophysical observables, such as the nonhydrostatic geoid, free-air gravity anomalies, and dynamic surface topography, and provide constraints on internal mantle density structure. The convection related observables are corrected for the isostatically compensated crustal heterogeneity and compared with those predicted by tomography-based mantle flow models. Occam inversions of the surface topography and gravity data provide inferences of the velocity–density scaling coefficients, which characterize mantle density anomalies below North America. The inferred density anomalies require simultaneous contributions from temperature and composition. The density and seismic shear velocity anomalies place constraints on the thermochemical structure of the mantle beneath the North American craton. Perturbations in the molar ratio of iron, R = XFe/(XFe + XMg), are used to quantify the compositional anomalies in terms of iron depletion in the sub-continental mantle. Estimates of the extent of basalt depletion in the tectosphere beneath North America are obtained. This depletion is interpreted to produce a local balance between positive chemical buoyancy and the negative thermal buoyancy that would otherwise be produced by the colder temperatures of the sub-cratonic mantle relative to its sub-oceanic counterpart.

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Davies, Geoffrey F. "Early mantle dynamics: Depletion, plates and a revised cooling history." Geochimica et Cosmochimica Acta 70, no. 18 (August 2006): A132. http://dx.doi.org/10.1016/j.gca.2006.06.280.

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12

Courtillot, Vincent, and Peter Olson. "Mantle plumes link magnetic superchrons to phanerozoic mass depletion events." Earth and Planetary Science Letters 260, no. 3-4 (August 2007): 495–504. http://dx.doi.org/10.1016/j.epsl.2007.06.003.

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13

Akizawa, Norikatsu, Asuka Yamaguchi, Kenichiro Tani, Akira Ishikawa, Ryo Fujita, and Sung Hi Choi. "Highly refractory dunite formation at Gibbs Island and Bruce Bank, and its role in the evolution of the circum-Antarctic continent." Canadian Mineralogist 59, no. 6 (November 1, 2021): 1731–53. http://dx.doi.org/10.3749/canmin.2100030.

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ABSTRACT The continental margin is of profound importance as it records continental growth by accretion of orogenic magmas and following continental rifting. A high degree of mantle melting due to hydrous fluid input is expected to simultaneously stimulate continental growth and lower the intrinsic density of the mantle than more fertile mantle, which in turn isolates the continental lithosphere from the convective mantle. The mantle peridotites from Gibbs Island (South Shetland Islands) and Bruce Bank in the Drake Passage provide us an insight into the tectonic history in the circum-Antarctic region. To elucidate the continental growth of Antarctica, we present geochemical data of eight dunites from Gibbs Island and one dunite from Bruce Bank, including Re–Os isotope and highly siderophile element compositions. The dunites are severely affected by serpentinization as evidenced by antigorite + brucite or lizardite (loss on ignition = LOI ranging from 3 to 34 wt.%) but contain primary euhedral to subhedral chromites with or without spherical inclusions. The chromites rarely form lens-shaped aggregates. A dunite from Gibbs Island contains fresh olivine grains filling a fracture in the chromite with low LOI (3 wt.%), indicating a deserpentinization origin from a precursor serpentinized dunite. The dunites show highly depleted bulk-rock major element compositions (Mg/Si = 1.4–1.6 and Al/Si = 0.004–0.01 for Gibbs Island dunites, Mg/Si = 0.66 and Al/Si = 0.008 for Bruce Bank dunite), overlapping a compositional field defined by forearc peridotites. The positive correlation in Re/Ir–LOI space corroborates Re input during the later serpentinization process. The 187Os/188Os ratios of the dunites range from 0.11907 to 0.14493. Phanerozoic Re-depletion (melt depletion) ages of ca. 535–129 Ma are recorded in the Gibbs Island dunites, except for one with a Mesoproterozoic Re-depletion age of ca. 1.2 Ga. Since there exists serpentinization-related perturbation of Re, the ages provide minimum time estimates for melt depletion events. The early Paleozoic melt depletion is inferred to have occurred at a very early stage of Antarctic Peninsula formation in response to plate convergence along the margin of Gondwana, whereas the Mesoproterozoic Re-depletion age reflects convecting mantle heterogeneity unrelated to any nearby crust-forming events. The petrographic characteristics of the chromites and highly depleted nature of the dunites are attributed to melt–peridotite reaction in a subduction zone setting. A feasible interpretation for the dunite formation is that the mantle had experienced two stages of melting with the final stage occurring along the Gondwana continental margin in the subduction zone setting. Resultant highly refractory lithospheric mantle was later displaced and dispersed during the Gondwana breakup. Widespread existence of the dunite may be attributed to multi-stage melt depletion along the continental margin.

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14

Scott, James M., Jingao Liu, D. Graham Pearson, and Tod E. Waight. "Mantle depletion and metasomatism recorded in orthopyroxene in highly depleted peridotites." Chemical Geology 441 (November 2016): 280–91. http://dx.doi.org/10.1016/j.chemgeo.2016.08.024.

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15

Mohanty, Suchismita, Atish Mohanty, Natalie Sandoval, Thai Tran, Victoria Bedell, Jun Wu, Anna Scuto, Joyce Murata-Collins, Dennis D. Weisenburger, and Vu N. Ngo. "Cyclin D1 depletion induces DNA damage in mantle cell lymphoma lines." Leukemia & Lymphoma 58, no. 3 (June 24, 2016): 676–88. http://dx.doi.org/10.1080/10428194.2016.1198958.

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16

Irifune, Tetsuo, Toru Shinmei, Catherine A. McCammon, Nobuyoshi Miyajima, David C. Rubie, and Daniel J. Frost. "Iron Partitioning and Density Changes of Pyrolite in Earth’s Lower Mantle." Science 327, no. 5962 (December 3, 2009): 193–95. http://dx.doi.org/10.1126/science.1181443.

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Phase transitions and the chemical composition of minerals in Earth’s interior influence geophysical interpretations of its deep structure and dynamics. A pressure-induced spin transition in olivine has been suggested to influence iron partitioning and depletion, resulting in a distinct layered structure in Earth’s lower mantle. For a more realistic mantle composition (pyrolite), we observed a considerable change in the iron-magnesium partition coefficient at about 40 gigapascals that is explained by a spin transition at much lower pressures. However, only a small depletion of iron is observed in the major high-pressure phase (magnesium silicate perovskite), which may be explained by preferential retention of the iron ion Fe3+. Changes in mineral proportions or density are not associated with the change in partition coefficient. The observed density profile agrees well with seismological models, which suggests that pyrolite is a good model composition for the upper to middle parts of the lower mantle.

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17

Deng, F. L., and J. D. Macdougall. "Proterozoic depletion of the lithosphere recorded in mantle xenoliths from Inner Mongolia." Nature 360, no. 6402 (November 1992): 333–36. http://dx.doi.org/10.1038/360333a0.

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18

Caulfield, J. T., S. P. Turner, A. Dosseto, N. J. Pearson, and C. Beier. "Source depletion and extent of melting in the Tongan sub-arc mantle." Earth and Planetary Science Letters 273, no. 3-4 (September 2008): 279–88. http://dx.doi.org/10.1016/j.epsl.2008.06.040.

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19

Wang, Wei, Fengyou Chu, Xichang Wu, Zhenggang Li, Ling Chen, Xiaohu Li, Yuanzi Yan, and Jie Zhang. "Constraining Mantle Heterogeneity beneath the South China Sea: A New Perspective on Magma Water Content." Minerals 9, no. 7 (July 4, 2019): 410. http://dx.doi.org/10.3390/min9070410.

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The nature of upper mantle is important to understand the evolution of the South China Sea (SCS); thus, we need better constrains on its mantle heterogeneity. Magma water concentration is a good indicator, but few data have been reported. However, the rarity of glass and melt inclusions and the special genesis for phenocrysts in SCS basalts present challenges to analyzing magmatic water content. Therefore, it is possible to estimate the water variations through the characteristics of partial melting and magma crystallization. We evaluated variations in Fe depletion, degree of melt fractions, and mantle source composition along the fossil spreading ridge (FSR) using SCS basalt data from published papers. We found that lava from the FSR 116.2° E, FSR 117.7° E, and non-FSR regions can be considered normal lava with normal water content; in contrast, lava from the FSR 117° E-carbonatite and 114.9–115.0° E basalts have higher water content and show evidence of strong Fe depletion during the fractional crystallization after elimination of the effects of plagioclase oversaturation. The enriched water in the 117° E-carbonatite basalts is contained in carbonated silicate melts, and that in the 114.9–115.0° E basalts results from mantle contamination with the lower continental crust. The lava from the 117° E-normal basalt has much lower water content because of the lesser influence of the Hainan plume. Therefore, there must be a mantle source compositional transition area between the southwestern and eastern sub-basins of the SCS, which have different mantle evolution histories. The mantle in the west is more affected by contamination with continental materials, while that in the east is more affected by the Hainan mantle plume.

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Bergin, Edwin A. "Chemical Models of Collapsing Envelopes." Symposium - International Astronomical Union 197 (2000): 51–60. http://dx.doi.org/10.1017/s0074180900164678.

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We discuss recent models of chemical evolution in the developing and collapsing protostellar envelopes associated with low-mass star formation. In particular, the effects of depletion of gas-phase molecules onto grain surfaces is considered. We show that during the middle to late evolutionary stages, prior to the formation of a protostar, various species selectively deplete from the gas phase. The principal pattern of selective depletions is the depletion of sulfur-bearing molecules relative to nitrogen-bearing species: NH3 and N2H+. This pattern is shown to be insensitive to the details of the dynamics and marginally sensitive to whether the grain mantle is dominated by polar or non-polar molecules. Based on these results we suggest that molecular ions are good tracers of collapsing envelopes. The effects of coupling chemistry and dynamics on the resulting physical evolution are also examined. Particular attention is paid to comparisons between models and observations.

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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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McCarthy, Anders, and Othmar Müntener. "Ancient depletion and mantle heterogeneity: Revisiting the Permian-Jurassic paradox of Alpine peridotites." Geology 43, no. 3 (March 2015): 255–58. http://dx.doi.org/10.1130/g36340.1.

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23

Okamura, Satoshi, Mitsuru Inaba, Yoshiko Adachi, and Ryuichi Shinjo. "Miocene-Pliocene mantle depletion event in the northern Fossa Magna, western NE Japan." Journal of Geodynamics 97 (July 2016): 42–61. http://dx.doi.org/10.1016/j.jog.2016.03.007.

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Pearson, N. J., W. L. Griffin, O. Alard, and Suzanne Y. O'Reilly. "The isotopic composition of magnesium in mantle olivine: Records of depletion and metasomatism." Chemical Geology 226, no. 3-4 (February 2006): 115–33. http://dx.doi.org/10.1016/j.chemgeo.2005.09.029.

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25

Jha, Kopal, E. M. Parmentier, and Jason Phipps Morgan. "The role of mantle-depletion and melt-retention buoyancy in spreading-center segmentation." Earth and Planetary Science Letters 125, no. 1-4 (July 1994): 221–34. http://dx.doi.org/10.1016/0012-821x(94)90217-8.

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Azbel, I. Ya, I. N. Tolstikhin, D. Kramers, V. Pechernikova, and A. V. Vityazev. "Core growth and siderophile element depletion of the mantle during homogeneous Earth accretion." Geochimica et Cosmochimica Acta 57, no. 12 (June 1993): 2889–98. http://dx.doi.org/10.1016/0016-7037(93)90396-e.

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Hanghøj, Karen, Peter Kelemen, Stefan Bernstein, Jerzy Blusztajn, and Robert Frei. "Osmium isotopes in the Wiedemann Fjord mantle xenoliths: A unique record of cratonic mantle formation by melt depletion in the Archaean." Geochemistry, Geophysics, Geosystems 2, no. 1 (January 2001): n/a. http://dx.doi.org/10.1029/2000gc000085.

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Edwards, Stephen J., and John Malpas. "Multiple origins for mantle harzburgites: examples from the Lewis Hills, Bay of Islands ophiolite, Newfoundland." Canadian Journal of Earth Sciences 32, no. 7 (July 1, 1995): 1046–57. http://dx.doi.org/10.1139/e95-086.

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Harzburgite is a common rock type in ophiolites and alpine peridotites. It is considered to be typical of a residual mantle mineralogy, i.e., material left behind after periods of extensive mantle melting and melt–rock and fluid–rock interactions that produce a variety of basaltic melts. The processes by which these melts and residua are produced are complicated; therefore, to fully understand them, it is necessary to undertake detailed and integrated field, petrographic, and geochemical studies of large exposures of mantle material as part of the investigative process. Such a study in the Bay of Islands ophiolite exposed in the Lewis Hills of Newfoundland has enabled the identification of four major types of harzburgite, which represent examples of a complete spectrum of this rock type. Depleted, residual harzburgite and associated dunite, with positive-sloping rare earth element patterns, may develop U-shaped rare earth element patterns and a visible orthopyroxene enrichment by the introduction of a component of high-Mg, quartz-normative melt, or a hydrous fluid component with a high Si/Al ratio. Conversely, U-shaped rare earth element patterns and apparent orthopyroxene depletion may occur by the addition of low-Si/Al, hydrous fluid. Such enrichments and depletions of orthopyroxene by solution–precipitation reactions may result not only in the variety of harzburgite types, which on partial melting might produce a range of melt products, but also in fronts of harzburgite migrating through the mantle.

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Amelin, Yuri, Sandra L. Kamo, and Der-Chuen Lee. "Evolution of early crust in chondritic or non-chondritic Earth inferred from U–Pb and Lu–Hf data for chemically abraded zircon from the Itsaq Gneiss Complex, West GreenlandThis article is one of a series of papers published in this Special Issue on the theme of Geochronology in honour of Tom Krogh." Canadian Journal of Earth Sciences 48, no. 2 (February 2011): 141–60. http://dx.doi.org/10.1139/e10-091.

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Zircon grains in rocks collected from the Itsaq Gneiss Complex, southwest Greenland, were analyzed for U–Pb and Lu–Hf in the same grain using isotope dilution – thermal ionization mass spectrometry (TIMS) and multicollector – inductively coupled plasma – mass spectrometry (MC–ICP–MS). Grains were pretreated using chemical abrasion or air abrasion to assure that only zircon material unaffected by the migration of parent and daughter elements was analyzed. The data are consistent with derivation of all studied rocks from a single enriched mantle source or mafic crustal protolith with 176Lu/177Hf of 0.022 ± 0.003 that was repeatedly melted and produced tonalitic magmas. The assessment of the primary mantle source from which this mafic protolith was derived, at or before 3.85 Ga, greatly depends on the assumed composition of the bulk silicate Earth. Using the currently accepted Lu–Hf bulk Earth parameters based on the analysis of chondrites yields εHf(T) of 0 to +1 for the 3.80–3.86 Ga rocks, suggesting that the protolith was derived from mantle that underwent moderate depletion shortly before 3.9 Ga. However, using alternative models of the bulk silicate Earth composition, i.e., that account for the possible irradiation-induced accelerated decay of 176Lu in the early Solar System, and (or) loss of the products of early planetesimal or planetary differentiation, can lead to widely variable interpretations of the enrichment or depletion history of the mantle source of the Itsaq protolith.

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Anderson, Don L. "A model to explain the various paradoxes associated with mantle noble gas geochemistry." Proceedings of the National Academy of Sciences 95, no. 16 (August 4, 1998): 9087–92. http://dx.doi.org/10.1073/pnas.95.16.9087.

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As a result of an energetic accretion, the Earth is a volatile-poor and strongly differentiated planet. The volatile elements can be accounted for by a late veneer (≈1% of total mass of the Earth). The incompatible elements are strongly concentrated into the exosphere (atmosphere, oceans, sediments, and crust) and upper mantle. Recent geochemical models invoke a large primordial undegassed reservoir with chondritic abundances of uranium and helium, which is clearly at odds with mass and energy balance calculations. The basic assumption behind these models is that excess “primordial” 3He is responsible for 3He/4He ratios higher than the average for midocean ridge basalts. The evidence however favors depletion of 3He and excessive depletion of 4He and, therefore, favors a refractory, residual (low U, Th) source Petrological processes such as melt-crystal and melt-gas separation fractionate helium from U and Th and, with time, generate inhomogeneities in the 3He/4He ratio. A self-consistent model for noble gases involves a gas-poor planet with trapping of CO2 and noble gases in the shallow mantle. Such trapped gases are released by later tectonic and magmatic processes. Most of the mantle was depleted and degassed during the accretion process. High 3He/4He gases are viewed as products of ancient gas exsolution stored in low U environments, rather than products of primordial reservoirs.

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Nédli, Zsuzsanna, Csaba Szabó, and Júlia Dégi. "Orthopyroxene-enrichment in the lherzolite-websterite xenolith suite from Paleogene alkali basalts of the Poiana Ruscă Mountains (Romania)." Geologica Carpathica 66, no. 6 (December 1, 2015): 499–514. http://dx.doi.org/10.1515/geoca-2015-0041.

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Abstract In this paper we present the petrography and geochemistry of a recently collected lherzolite-websterite xenolith series and of clinopyroxene xenocrysts, hosted in Upper Cretaceous–Paleogene basanites of Poiana Ruscă (Romania), whose xenoliths show notable orthopyroxene-enrichment. In the series a slightly deformed porphyroclastic-equigranular textured series could represent the early mantle characteristics, and in many cases notable orthopyroxene growth and poikilitic texture formation was observed. The most abundant mantle lithology, Type A xenoliths have high Al and Na-contents but low mg# of the pyroxenes and low cr# of spinel suggesting a low degree (< 10 %) of mafic melt removal. They are also generally poor in overall REE-s (rare earth elements) and have flat REY (rare earth elements+ Y) patterns with slight LREE-depletion. The geochemistry of the Type A xenoliths and calculated melt composition in equilibrium with the xenolith clinopyroxenes suggests that the percolating melt causing the poikilitization can be linked to a mafic, Al-Na-rich, volatile-poor melt and show similarity with the Late Cretaceous–Paleogene (66–72 Ma) subduction-related andesitic magmatism of Poiana Ruscă. Type B xenoliths, with their slightly different chemistry, suggest that, after the ancient depletion, the mantle went through a slight metasomatic event. A subsequent passage of mafic melts in the mantle, with similar compositions to the older andesitic magmatism of Poiana Ruscă, is recorded in the pyroxenites (Fe-rich xenoliths), whereas the megacrysts seem to be cogenetic with the host basanite. The Poiana Ruscă xenoliths differ from the orthopyroxene-enriched mantle xenoliths described previously from the Carpathian-Pannonian Region and from the Dacia block.

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Neelapu, Sattva S., Larry W. Kwak, Carol B. Kobrin, Craig W. Reynolds, John E. Janik, Kieron Dunleavy, Therese White, et al. "Vaccine-induced tumor-specific immunity despite severe B-cell depletion in mantle cell lymphoma." Nature Medicine 11, no. 9 (August 21, 2005): 986–91. http://dx.doi.org/10.1038/nm1290.

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33

Czertowicz, T. A., J. M. Scott, T. E. Waight, J. M. Palin, Q. H. A. Van der Meer, P. Le Roux, C. Münker, and S. Piazolo. "The Anita Peridotite, New Zealand: Ultra-depletion and Subtle Enrichment in Sub-arc Mantle." Journal of Petrology 57, no. 4 (February 20, 2016): 717–50. http://dx.doi.org/10.1093/petrology/egw001.

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Ducea, Mihai, Gautam Sen, John Eiler, and Jennifer Fimbres. "Melt depletion and subsequent metasomatism in the shallow mantle beneath Koolau volcano, Oahu (Hawaii)." Geochemistry, Geophysics, Geosystems 3, no. 2 (February 2002): n/a. http://dx.doi.org/10.1029/2001gc000184.

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Xiong, X. L., B. Xia, J. F. Xu, H. C. Niu, and W. S. Xiao. "Na depletion in modern adakites via melt/rock reaction within the sub-arc mantle." Chemical Geology 229, no. 4 (May 2006): 273–92. http://dx.doi.org/10.1016/j.chemgeo.2005.11.008.

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Manglik, A., and U. R. Christensen. "Effect of mantle depletion buoyancy on plume flow and melting beneath a stationary plate." Journal of Geophysical Research: Solid Earth 102, B3 (March 10, 1997): 5019–28. http://dx.doi.org/10.1029/96jb03623.

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Chenin, Pauline, Suzon Jammes, Luc L. Lavier, Gianreto Manatschal, Suzanne Picazo, Othmar Müntener, Garry D. Karner, Patricio H. Figueredo, and Christopher Johnson. "Impact of Mafic Underplating and Mantle Depletion on Subsequent Rifting: A Numerical Modeling Study." Tectonics 38, no. 7 (July 2019): 2185–207. http://dx.doi.org/10.1029/2018tc005318.

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Sunita Jadhav. "Effect of Endosulfan on Protein Content of Freshwater Bivalve Corbicula Striatella." International Journal of Research in Informative Science Application & Techniques (IJRISAT) 2, no. 7 (February 13, 2022): 15–17. http://dx.doi.org/10.46828/ijrisat.v2i7.36.

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The protein content of freshwater bivalve, Corbicula striatella was studied after exposure to endosulfan. Overall depletion in proteins content in mantle, foot, gill, digestive gland and whole body was observed. The study was carried for median lethal (0.314) and sublethal (0.068).ISO 14001 standards of EMS.

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39

Portner, H. O., D. M. Webber, R. K. O'Dor, and R. G. Boutilier. "Metabolism and energetics in squid (Illex illecebrosus, Loligo pealei) during muscular fatigue and recovery." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 265, no. 1 (July 1, 1993): R157—R165. http://dx.doi.org/10.1152/ajpregu.1993.265.1.r157.

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The concentrations of intermediate and end products of anaerobic energy metabolism and of free amino acids were determined in mantle musculature and blood sampled from cannulated, unrestrained squid (Loligo pealei, Illex illecebrosus) under control conditions, after fatigue from increasing levels of exercise, and during postexercise recovery. Phosphagen depletion, accumulation of octopine (more so in Illex than in Loligo), and accumulation of succinate indicate that anaerobic metabolism contributes to energy production before fatigue. Proline was a substrate of metabolism in Loligo, as indicated by its depletion in the mantle. In both species, there was no evidence of catabolism of ATP beyond AMP. A comparison of the changes in the free and total levels of adenylates and the phosphagen indicates an earlier detrimental effect of fatigue on the energy status in Loligo. The acidosis provoked by octopine formation in Illex was demonstrated to promote the use of the phosphagen and to protect the free energy change of ATP such that the anaerobic scope of metabolism during swimming is extended and expressed more in Illex than in Loligo. In both species, there was no decrease in the sum of phospho-L-arginine, octopine, and L-arginine, and thus no release of octopine from the mantle, thereby supporting our earlier claim that octopine and associated protons are recycled in the mantle tissue. Overall, the metabolic strategy of Loligo is much less disturbing for the acid-base status. This strategy and the alternative strategy of Illex to keep acidifying protons in the tissue may be important for the protection of hemocyanin function in the two species.

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Kepezhinskas, Pavel K., Glenn M. D. Eriksen, and Nikita P. Kepezhinskas. "Geochemistry of Ultramafic to Mafic Rocks in the Norwegian Lapland: Inferences on Mantle Sources and Implications for Diamond Exploration." Earth Science Research 5, no. 2 (July 28, 2016): 148. http://dx.doi.org/10.5539/esr.v5n2p148.

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Geology of the Norwegian Lapland is dominated by diverse Archean crystalline basement complexes superimposed with Proterozoic greenstone belts. Isotopic dating of detrital zircons from basement gneisses in the Kirkenes area establishes presence of Early Archean (3.69 Ga) crustal component as well as three major episodes of crustal growth at 3.2 Ga, 2.7-2.9 Ga and 2.5 Ga. Precambrian terranes are intruded by ultramafic-mafic dikes and sills that range in composition from komatiites and ultramafic-mafic lamprophyres to high-Mg basalts and low-Ti subalkaline basalts. Geochemical characteristics of these rocks fall into three principal groups: 1) enriched compositions with high Nd, Nb, Hf, Zr and Th concentrations and elevated La/Th and Nb/Th coupled with low La/Nb, Ba/Nb and U/Nb ratios; 2) compositions depleted in Th, Hf and Nb together with low LREE/HFSE (such as La/Nb) and LILE/HFSE (such as Ba/Nb and U/Nb) ratios; 3) transitional group clearly identified by marked depletions in Ti, Nb and Ta contents coupled with enrichment in Th and U and other large-ion lithophile elements (LILE). These geochemical characteristics are interpreted within the framework of two principal source models: 1) derivation of parental ultramafic-mafic melts from multiple mantle sources (depleted to enriched) inherited from Archaean lithospheric tectonics and 2) a single primitive mantle source which underwent several depletion and enrichment episodes, at least partially associated with subduction zone processes. Subduction modification of depleted lithospheric mantle was assisted by accretion of subducted sediment to depleted mantle source at Archean, Proterozoic or Early Paleozoic convergent margin. Alkaline ultramafic rocks such as lamprophyres and mica picrites display geochemical characteristics supportive of their origin within stability field of diamond in a deep mantle beneath Norwegian Arctic margin which, together with other lithospheric characteristics, suggests its high potential for hosting economic diamond mineralization.

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Newton, David E., Maya G. Kopylova, Jennifer Burgess, and Pamela Strand. "Peridotite and pyroxenite xenoliths from the Muskox kimberlite, northern Slave craton, Canada." Canadian Journal of Earth Sciences 53, no. 1 (January 2016): 41–58. http://dx.doi.org/10.1139/cjes-2015-0083.

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We present petrography, mineralogy, and thermobarometry for 53 mantle-derived xenoliths from the Muskox kimberlite pipe in the northern Slave craton. The xenolith suite includes 23% coarse peridotite, 9% porphyroclastic peridotite, 60% websterite, and 8% orthopyroxenite. Samples primarily comprise forsteritic olivine (Fo 89–94), enstatite (En 89–94), Cr-diopside, Cr-pyrope garnet, and chromite spinel. Coarse peridotites, porphyroclastic peridotites, and pyroxenites equilibrated at 650–1220 °C and 23–63 kbar (1 kbar = 100 MPa), 1200–1350 °C and 57–70 kbar, and 1030–1230 °C and 50–63 kbar, respectively. The Muskox xenoliths differ from xenoliths in the neighboring and contemporaneous Jericho kimberlite by their higher levels of depletion, the presence of a shallow zone of metasomatism in the spinel peridotite field, a higher proportion of pyroxenites at the base of the mantle column, higher Cr2O3 in all pyroxenite minerals, and weaker deformation in the Muskox mantle. We interpret these contrasts as representing small-scale heterogeneities in the bulk composition of the mantle, as well as the local effects of interaction between metasomatizing fluid and mantle wall rocks. We suggest that asthenosphere-derived pre-kimberlitic melts and fluids percolated less effectively through the less permeable Muskox mantle, resulting in lower degrees of hydrous weakening, strain, and fertilization of the peridotitic mantle. Fluids tended to concentrate and pool in the deep mantle, causing partial melting and formation of abundant pyroxenites.

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Foden, J. "Ultra-depletion of the mantle and the development of boninite on the initiation of subduction." Geochimica et Cosmochimica Acta 70, no. 18 (August 2006): A179. http://dx.doi.org/10.1016/j.gca.2006.06.360.

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Gruau, G., C. Chauvel, N. T. Arndt, and J. Cornichet. "Aluminum depletion in komatiites and garnet fractionation in the early Archean mantle: Hafnium isotopic constraints." Geochimica et Cosmochimica Acta 54, no. 11 (November 1990): 3095–101. http://dx.doi.org/10.1016/0016-7037(90)90125-5.

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Davies, Geoffrey F. "Gravitational depletion of the early Earth's upper mantle and the viability of early plate tectonics." Earth and Planetary Science Letters 243, no. 3-4 (March 2006): 376–82. http://dx.doi.org/10.1016/j.epsl.2006.01.053.

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Steenstra, E. S., D. Dankers, J. Berndt, S. Klemme, S. Matveev, and W. van Westrenen. "Significant depletion of volatile elements in the mantle of asteroid Vesta due to core formation." Icarus 317 (January 2019): 669–81. http://dx.doi.org/10.1016/j.icarus.2018.08.020.

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Lee, Cin-Ty A., Peter Luffi, Emily J. Chin, Romain Bouchet, Rajdeep Dasgupta, Douglas M. Morton, Veronique Le Roux, Qing-zhu Yin, and Daphne Jin. "Copper Systematics in Arc Magmas and Implications for Crust-Mantle Differentiation." Science 336, no. 6077 (April 5, 2012): 64–68. http://dx.doi.org/10.1126/science.1217313.

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Arc magmas are important building blocks of the continental crust. Because many arc lavas are oxidized, continent formation is thought to be associated with oxidizing conditions. On the basis of copper’s (Cu’s) affinity for reduced sulfur phases, we tracked the redox state of arc magmas from mantle source to emplacement in the crust. Primary arc and mid-ocean ridge basalts have identical Cu contents, indicating that the redox states of primitive arc magmas are indistinguishable from that of mid-ocean ridge basalts. During magmatic differentiation, the Cu content of most arc magmas decreases markedly because of sulfide segregation. Because a similar depletion in Cu characterizes global continental crust, the formation of sulfide-bearing cumulates under reducing conditions may be a critical step in continent formation.

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Haase, Karsten M., and Christoph Beier. "Chapter 3.2b Bransfield Strait and James Ross Island: petrology." Geological Society, London, Memoirs 55, no. 1 (2021): 285–301. http://dx.doi.org/10.1144/m55-2018-37.

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AbstractYoung volcanic centres of the Bransfield Strait and James Ross Island occur along back-arc extensional structures parallel to the South Shetland island arc. Back-arc extension was caused by slab rollback at the South Shetland Trench during the past 4 myr. The variability of lava compositions along the Bransfield Strait results from varying degrees of mantle depletion and input of a slab component. The mantle underneath the Bransfield Strait is heterogeneous on a scale of approximately tens of kilometres with portions in the mantle wedge not affected by slab fluids. Lavas from James Ross Island east of the Antarctic Peninsula differ in composition from those of the Bransfield Strait in that they are alkaline without evidence for a component from a subducted slab. Alkaline lavas from the volcanic centres east of the Antarctic Peninsula imply variably low degrees of partial melting in the presence of residual garnet, suggesting variable thinning of the lithosphere by extension. Magmas in the Bransfield Strait form by relatively high degrees of melting in the shallow mantle, whereas the magmas some 150 km further east form by low degrees of melting deeper in the mantle, reflecting the diversity of mantle geodynamic processes related to subduction along the South Shetland Trench.

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González-Jiménez, José, Sisir Mondal, Biswajit Ghosh, William Griffin, and Suzanne O’Reilly. "Re-Os Isotope Systematics of Sulfides in Chromitites and Host Lherzolites of the Andaman Ophiolite, India." Minerals 10, no. 8 (July 31, 2020): 686. http://dx.doi.org/10.3390/min10080686.

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Laser ablation MC-ICP-MS was used to measure the Os-isotope compositions of single sulfide grains, including laurite (RuS2) and pentlandite [(Fe,Ni)9S8], from two chromitite bodies and host lherzolites from ophiolites of North Andaman (Indo-Burma-Sumatra subduction zone). The results show isotopic heterogeneity in both laurite (n = 24) and pentlandite (n = 37), similar to that observed in other chromitites and peridotites from the mantle sections of ophiolites. Rhenium-depletion model ages (TRD) of laurite and pentlandite reveal episodes of mantle magmatism and/or metasomatism in the Andaman mantle predating the formation of the ophiolite (and the host chromitites), mainly at ≈0.5, 1.2, 1.8, 2.1 and 2.5 Ga. These ages match well with the main tectonothermal events that are documented in the continental crustal rocks of South India, suggesting that the Andaman mantle (or its protolith) had a volume of lithospheric mantle once underlaying this southern Indian continental crust. As observed in other oceanic lithospheres, blocks of ancient subcontinental lithospheric mantle (SCLM) could have contributed to the development of the subduction-related Andaman–Java volcanic arc. Major- and trace-element compositions of chromite indicate crystallization from melts akin to high-Mg IAT and boninites during the initial stages of development of this intra-oceanic subduction system.

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Dostal, J., G. D. Jackson, and A. Galley. "Geochemistry of Neohelikian Nauyat plateau basalts, Borden rift basin, northwestern Baffin Island, Canada." Canadian Journal of Earth Sciences 26, no. 11 (November 1, 1989): 2214–23. http://dx.doi.org/10.1139/e89-188.

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Subaerial basalt flows of the Neohelikian Nauyat Formation from northwestern Baffin Island, Northwest Territories, constitute an approximately 360 m thick unit that overlies an Archean–Aphebian metamorphic basement. The lavas have undergone a low-grade regional metamorphism that affected the abundances of Na, K, and related trace elements. The basalts are continental tholeiites possessing some characteristics of mid-ocean-ridge basalts. They underwent fractional crystallization of clinopyroxene, plagioclase, and olivine. Mantle-normalized patterns show an enrichment of the lithophile elements, including Th and light rare-earth elements, relative to the high-field-strength elements and a distinct depletion of Nb and Sr. The parental magma of the basalts was derived either from oceanic-type mantle and subsequently affected by lower crustal contamination or from the subcontinental lithospheric mantle. The Nauyat basalts are probably related to the initial stage of the opening of the Poseidon (Proto-Arctic) Ocean.

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Arai, Shoji, Akihiro Tamura, Makoto Miura, and Kazuma Seike. "Abyssal Peridotite as a Component of Forearc Mantle: Inference from a New Mantle Xenolith Suite of Bankawa in the Southwest Japan Arc." Minerals 8, no. 11 (November 21, 2018): 540. http://dx.doi.org/10.3390/min8110540.

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Lithology and petrologic nature of the forearc mantle have been left unclear due to the very limited sampling to date. Here, we present petrological data on a forearc peridotite suite obtained as xenoliths in an alkali basalt dike (7.5 Ma) from the Bankawa area in the Southwest Japan arc for our better understanding of the forearc mantle. The host alkali basalt is of asthenosphere origin, and passed through a slab window with slight chemical modification by the slab-derived component. The Bankawa peridotite suite is comprised of lherzolites, which contain various amounts of secondary phlogopite and were metasomatized to various degrees. The least metasomatized lherzolite exhibits Fo91 of olivine, Cr/(Cr + Al) = 0.3 of chromian spinel, and depletion of middle to light rare-earth elements in clinopyroxene, and is overall similar to an abyssal lherzolite. It had originally formed at the proto-Pacific Ocean and then was trapped at a eastern margin of Eurasian continent by initiation of subduction. The forearc mantle peridotite formed as a residue of proto-arc magma formation is depleted harzburgite as represented by the peridotites obtained from the forearc seafloor, but can be less depleted abyssal peridotite if being devoid of partial melting or reaction with magmas after entrapment.

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Journal articles on the topic 'Mantle depletion'

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