 | | Journal (article/letter/editorial) | | from the deeper mantle section of the northern Oman ophiolite and its tectonic implications Received:...first time in a podiform chromitite of the northern Oman ophiolite. The chromitite contains £ 1.5 ppm of total...the mantle to the crust (Naldrett 1981; Garuti et al. 1997). PGE-abundance systematics give us information...the early stage of the planet’s history (Jagoutz et al. 1979; Arculus and Delano 1981; O’Neill 1991). PGEs...mineralogy of PGEs in the Oman ophiolite in general, especially in its northern part. We found high PGE |  | | Journal (article/letter/editorial) | | from the northern Oman ophiolite as the stratigraphically shallowest chromitite in ophiolite and its implication...podiform chromitite was found at Wadi Hilti in the northern Oman ophiolite. It is within a late-intrusive...chromitite is in the upper crust, by far shallower in ophiolite stratigraphy than the other podiform chromitites...chromitite from Oman has relatively low content of (Cr2O3 + Al2O3), the Cr/(Cr + Al) atomic ratio of...Thayer 1964, 1969; Dickey 1975; Cassard et al. 1981; Lago et al. 1982; Paktunc 1990; Leblanc and Nicolas |  | | Journal (article/letter/editorial) | | mantle processes: Observations from the northern Oman ophiolite Makoto Miura, Shoji Arai and Akihiro Tamura...examined in the mantle section of the northern Oman ophiolite along Wadi Hilti, to constrain its origin. Spinels...and adjacent peridotites show high Cr# (= Cr/(Cr + Al) atomic ratio), around 0.65 to 0.75, indicating an...supra-subduction zone environment just before ophiolite obduction. Such arc-related features in mantle...depleted harzburgites, Arc-related magmatism, Oman ophiolite, Obduction INTRODUCTION Ophiolites have been |  | | Journal (article/letter/editorial) | | magma in the reservoir [11]. Recently, Latypov et al. [14] argued for the importance of a pressure reduction...precipitate the stratiform chromitite (see Schulte et al. [2] for more details about stratiform chromitite)...chromitites [19,20] (Figure 1). The Cr# (= Cr/(Cr + Al) atomic ratio) of chromite is not so different; 0...and limited range of the Fe3+ ratio (Fe3+ /(Cr + Al + Fe3+ ) atomic ratio; <0.1) for the podiform chromitites...Cr/(Cr + Al) Minerals 2021, 11, 209 3 of 10 stratiform 0.5 stratiform podiform 3+ Fe Al 0.5 0 |  | | Journal (article/letter/editorial) | | precipitates pargasite and aspidolite (Na analogue of phlogopite), which are NU stable under upper mantle conditions...formation of chromite-oversaturated magmas. Spandler et al. (2005) found a mixing trend for the bulk CE chemical...around the chromitite (e.g., Cassard et al., 1981; Lago et al., 1982) (Fig. 1). Following the hypothesis...Yurimoto, 1994; Zhou et 4 ACCEPTED MANUSCRIPT al., 1994) (Fig. 2). Since then, podiform chromitites...various types (e.g., Proenza et al., 1999; Uysal et al., 2005; Borisova et al., 2012; Ahmed and Habtoor, 2015) |  | | Journal (article/letter/editorial) | | PLATINUM-GROUP MINERALS IN PODIFORM CHROMITITES OF THE OMAN OPHIOLITE AHMED HASSAN AHMED§ AND SHOJI ARAI Department...part of the mantle section of the northern part of the Oman ophiolite. In terms of stratigraphic level...abundance of PGE sulfides, i.e., Os-rich laurite, in the Oman chromitites is ascribed to the sulfide-undersaturated...chromitite, ophiolite, platinum-group elements, platinum-group minerals, sulfur fugacity, northern Oman. SOMMAIRE...la Rédaction) Mots-clés: laurite, chromitite, ophiolite, éléments du groupe du platine, minéraux du groupe |  | | Journal (article/letter/editorial) | | silicate inclusions (pyroxenes, pargasite and Na phlogopite), commonly found in the low-pressure chromitite...concordant and discordant chromitites from Oman ophiolite are of low-pressure origin, containing primary...ネル は の岩石の生成環境の指示者として重要である(例えば， (Mg, Fe2＋ )(Cr, Al, Fe3＋ )2O4 と表記されるが，他に Ti, Mn, Zn なども含み，その化学組成は極めて多様なことか... 上部マントルの主要な構成要素であるかんらん岩にはク みクロムスピネルの Cr /( Cr＋ Al )原子比 0.5 前後)であ ロムスピネルが 2 体積程度以下含まれる。かんらん岩の ることが多い(Arai...場合がある する。ポディフォーム・クロミタイトについては， 1980 (Cassard et al. 1981)(Fig. 1)。前者を非調和性クロミタイ ト( concordant chromitite |  | Tseng, C.-Y., Yang, H.-Y., Wu, H.-Q., Zuo, G.-C. (2007) THE SILICATE MINERAL INCLUSIONS IN THE CHROMIAN SPINEL FROM THE DONGCAOHE OPHIOLITE, NORTH QILIAN MOUNTAINS, NORTHWESTERN CHINA: RECORD OF SYNTEXIS OF LOWER OCEANIC CRUST. The Canadian Mineralogist, 45 (4) 793-808 doi:10.2113/gscanmin.45.4.793 | Journal (article/letter/editorial) | | INCLUSIONS IN THE CHROMIAN SPINEL FROM THE DONGCAOHE OPHIOLITE, NORTH QILIAN MOUNTAINS, NORTHWESTERN CHINA: RECORD...series and discordant layered bodies, Dongcaohe ophiolite, in the North Qilian Mountains, Qinghai Province...alteration or subsequent seafloor metamorphism of the ophiolite. Syntexis of the lower oceanic crust was involved...layered cumulate series of the Dongcaohe ophiolite. Keywords: ophiolite, mineral inclusions, chromian spinel...bodies, syntexis, lower oceanic crust, Dongcaohe ophiolite, Qinghai Province, People’s Republic of China |  | | Journal (article/letter/editorial) | | mantle level (e.g., Arai and Yurimoto, 1994; Zhou et al., 1994; Arai, 1997). The podiform chromitites serve...g., Robinson et al., 2004; Yang et al., 2007, 2011; Yamamoto et al., 2009; Xu et al., 2009), and this...discussed in great detail (e.g., Robinson et al., 2004; Ruskov et al., 2010). The important point is that, as...show nodular textures (e.g., Zhou et al., 1996; Yamamoto et al., 2009), which characterize igneous low-P...chromitites, enveloped by dunite (e.g., Cassard et al., 1981), are commonly found within mantle peridotites |  | | Journal (article/letter/editorial) | | contains chromite with an intermediate Cr# (Cr/(Cr + Al)) of 0.4–0.6 is the optimum host for chromitites...genuine MORB, they also form in the typical MA ophiolite tectonic setting, at supra-subduction zone spreading...Peridotite–melt reaction, Ridge segment center, Ophiolite, Mantle drilling 1. Introduction Podiform chromitites... PT (chromian spinel) with a high Cr# (Cr/(Cr + Al)) of 0.7–0.9, previous studies have reported SC...podiform chromitites from Maqsad, southern Oman ophiolite, which they interpreted to have formed in mid-ocean |  | | Journal (article/letter/editorial) | | variations to some discordant chromitites from the Oman ophiolite, a typical podiform chromitite interpreted...Takashima chromitite xenoliths indicate that the Oman discordant podiform chromitites were formed in a...a supra-subduction mantle setting before ophiolite obduction. Keywords: chromitite xenoliths, discordant...chromitites, laurite, Takashima alkali basalt, Oman ophiolite. INTRODUCTION Ultramafic xenoliths provide...representative of sub-arc upper mantle material (e.g., Arai et al. 2007, Arai & Ishimaru 2008). Chromitite xenoliths |  | Matsukage, K. N., Kikuchi, S., Ono, S., Nishihara, Y., Kikegawa, T. (2010) Density and seismic velocities of chromitite body in oceanic mantle peridotite. American Mineralogist, 95 (10) 1422-1428 doi:10.2138/am.2010.3498 | Journal (article/letter/editorial) | | from the Oman ophiolite were calculated and compared with those of oceanic peridotites. The Oman chromitite...Chromitite, oceanic peridotite, seismic velocities, ophiolite iNtroductioN Podiform chromitite bodies are locally...orogenic peridotite complexes and mantle sections of ophiolite all over the world. Although they exist only in...setting of the formation of igneous sections in ophiolite. Despite the considerable number of studies done...the formation of the igneous sequence of the Oman ophiolite, in which there are large chromitite bodies |  | Negishi, Hironori, Arai, Shoji, Yurimoto, Hisayoshi, Ito, Shoichi, Ishimaru, Satoko, Tamura, Akihiro, Akizawa, Norikatsu (2013) Sulfide-rich dunite within a thick Moho transition zone of the northern Oman ophiolite: Implications for the origin of Cyprus-type sulfide deposits. Lithos, 164. 22-35 doi:10.1016/j.lithos.2012.11.024 | Journal (article/letter/editorial) | | within a thick Moho transition zone of the northern Oman ophiolite: Implications for the origin of Cyprus-type...transition zone Cyprus-type sulfide deposits Oman ophiolite a b s t r a c t Peculiar dunites, in part...transition zone (MTZ) are found along Wadi Thuqbah in the northern Oman ophiolite. We discuss their relevance to...Mid-Atlantic Ridge (Hannington et al., 1998; Humphris and Cann, 2000; Humphris et al., 1995) as well as from ophiolites...ophiolites (e.g., Dergachev et al., 2010). Deep processes related to sea-floor sulfide deposit formation |  | | Journal (article/letter/editorial) | | of chromite by hydrothermal solutions in the Oman ophiolite: New behavior of Cr and chromite Shoji Arai*...metasomatically replacing the layered gabbro of the Oman ophiolite. The uvarovite shows oscillatory concentric...concentric zoning in terms of Cr no. [Cr/(Cr+Al)], and the chromite is embedded only in the high-Cr-no. zones...Mg/(Mg+Fe2+) = 0.1–0.2, TiO2 < 0.3 wt% and Fe3+/(Cr+Al+Fe3+), up to 0.3], but its Cr no. is clearly different...7) in peridotites and chromitites from the Oman ophiolite. The results from this study suggest that a |  | | Journal (article/letter/editorial) | | exsolution lamellae in chromite from the Semail ophiolite: Evidence for a high-pressure origin Tao Chen...Zhang, et al., Calcium amphibole exsolution lamellae in chromite from the Semail ophiolite: Evidence...exsolution lamellae in chromite from the Semail ophiolite: Evidence for a high-pressure origin State Key...chromitite from the Nakhl massif of the Semail T Ophiolite. Transmission electron microscopy observations...the Semail ophiolite. Keywords: Ca-amphibole exsolution, podiform chromitite, Semail ophiolite, hydroxyl |  | Miura, Makoto, Arai, Shoji, Mizukami, Tomoyuki, Shmelev, Vladimir, Ishimaru, Satoko (2018) Petrology of Chromitites in the Higashi-Akaishi Ultrahigh-Pressure (UHP) Peridotite Complex, Japan: Toward Understanding of General Features of the UHP Chromitites. Minerals, 8 (11) 525 doi:10.3390/min8110525 | Journal (article/letter/editorial) | | Podiform chromitites from ophiolites, such as the Oman ophiolite, commonly show various lines of evidence for...peridotites in several ophiolites such as Luobusa ophiolite [5–9] have been found from chromitites and surrounding...several ophiolites suchofasTibet Luobusa and Ray-Iz ophiolite of the Polar Urals [7]. Origin of such UHP mineral-bearing...mineral-bearing chromitites (UHP ophiolite of Tibet [5–9] and Ray‐Iz ophiolite of the Polar Urals [7]. Origin...Modified Modifiedfrom fromHattori Hattoriet etal. al.[17]. [17].Open Openstar, star, sampling sampling |  | Liu, Jianguo, Wang, Jian, Hattori, Keiko, Wang, Zeli, Zhang, Han (2019) Early Palaeozoic sub-arc chromitite-bearing peridotite in the Kudi ophiolite on the westernmost Tibetan Plateau. International Geology Review, 61 (9) 1105-1123 doi:10.1080/00206814.2018.1493623 | Journal (article/letter/editorial) | | sub-arc chromitite-bearing peridotite in the Kudi ophiolite on the westernmost Tibetan Plateau Jianguo Liu...sub-arc chromitite-bearing peridotite in the Kudi ophiolite on the westernmost Tibetan Plateau, International...sub-arc chromitite-bearing peridotite in the Kudi ophiolite on the westernmost Tibetan Plateau Jianguo Liua...A chromite deposit was discovered in the Kudi ophiolite in the Palaeozoic western Kunlun orogenic belt...Fo in olivine (88.1–90.9), moderate Cr# [=Cr/(Cr + Al), 0.47–0.56] in chromite, and a positively sloped |  | | Journal (article/letter/editorial) | | D classified into two main types: primary high-Al (spinel Cr# <0.67) and high-Cr (spinel Cr#> TE ...Balamhindit complex, where the chromitite showed K-phlogopite 1 ACCEPTED MANUSCRIPT inclusions within the...mineral inclusions, K-phlogopites, Neoproterozoic ophiolite, 1. Introduction CE P Eastern Desert of Egypt...and high-Al) in the mantle section (e.g., Zhou et al., 1998; Uysal et al., 2009; Miura et al., 2012; Akmaz...Akmaz et al., 2014; Moghadam et al., 2015). The high-Cr chromitites have been in equilibrium with boninitic |  | González-Jiménez, José María, Griffin, William L., Proenza, Joaquín A., Gervilla, Fernando, O'Reilly, Suzanne Y., Akbulut, Mehmet, Pearson, Norman J., Arai, Shoji (2014) Chromitites in ophiolites: How, where, when, why? Part II. The crystallization of chromitites. Lithos, 189. 140-158 doi:10.1016/j.lithos.2013.09.008 | Journal (article/letter/editorial) | | shows no consistent spatial location within the ophiolite “stratigraphy”. The second type (Type IIA) is...occur usually in the upper-mantle part of the ophiolite pseudosection, or near the crust-mantle boundary...Melcher et al., 1999; Proenza et al., 1999; Ahmed and Arai, 2002; Gervilla et al., 2005; Uysal et al., 2005...2008; Pagé and Barnes, 2009; Zaccarini et al., 2011; Borisova et al., 2012; Kapsiotis, 2013). Unraveling the...In this study, as in Part I (González-Jiménez et al., this volume), we accept the SC RI definitions |  | | Journal (article/letter/editorial) | | edu.cn) 7 ABSTRACT 8 Primary high-Al [Cr# = 100×Cr/(Cr+Al) of 48.2–54.7] chromitites coupled with...polymineralic mineral inclusions including Na-phlogopite, 15 enstatite, diopside, pargasite, olivine...and occasionally zircon 16 are found in the high-Al chromitites. Chemical compositions of these mineral...ppm; Ga = 11.2–13.3 ppm) in equilibrium with high-Al chromitites suggest that these 22 chromitites...back-arc basin 30 spreading ridge. Subsequently, high-Al chromitites were formed and mechanically 31 juxtaposed |  | | Book | | bin Said Al Shanfari Minister of Petroleum and Minerals The Speech of H.E. Said Bin Ahmed Al Shanfari...Symposium Your Royal Highness Sayed Fahad Bin Mahmoud al Said, Your Royal Highness Members of the Honourable...pleasure to welcome you in this scientific gathering in Oman which has been made possible through the directives...contribute to the advancement of earth sciences. We, in Oman look forward with keen interest to the outcome of... I wish to thank the Ministry of Defence, Royal Oman Police and the Ministry of Information for their |  | Su, Ben-Xun, Robinson, Paul T., Chen, Chen, Xiao, Yan, Melcher, Frank, Bai, Yang, Gu, Xiao-Yan, Uysal, Ibrahim, Lenaz, Davide (2020) The occurrence, origin, and fate of water in chromitites in ophiolites. American Mineralogist, 105 (6). 894-903 doi:10.2138/am-2020-7270 | Journal (article/letter/editorial) | | Podiform chromitite, clinopyroxene, olivine, ophiolite, water Introduction The discovery of various...chromitites of ophiolites (e.g., Robinson et al. 2004; Yang et al. 2007) has led to a renewed interest in...their parental magmas. It is widely thought that high-Al and high-Cr chromitites are crystallized from mid-ocean...boninite-type melts, respectively (e.g., Zhou et al. 1996; Pagé and Barnes 2009). However, many details...amphibole, phlogopite, and fluids) in chromite (e.g., Melcher et al. 1997; Schiano et al. 1997; Borisova |  | Zhang, Yanfei, Jin, Zhenmin, Griffin, William L., Wang, Chao, Wu, Yao (2017) High-pressure experiments provide insights into the Mantle Transition Zone history of chromitite in Tibetan ophiolites. Earth and Planetary Science Letters, 463. 151-158 doi:10.1016/j.epsl.2017.01.036 | Journal (article/letter/editorial) | | b s t r a c t The chromitites in the Luobusha ophiolite (Tibet) have been proposed as messengers from...O4 structure (idealized composition (Mg, Fe)(Cr, Al)2 O4 ), an indicator of Mantle Transition Zone (MTZ)...Introduction Podiform chromitites in the Luobusha ophiolite (southeastern Tibet) are typically lens-shaped...Cr/Cr + Al) and Mg# (molar Mg/Mg + Fe) of ∼0.7–0.8 and ∼0.70–0.76, respectively (e.g., Zhou et al., 2014;...2014; Zhang et al., 2016). Previous studies have shown that these chromitites can be explained by interaction |  | Xiong, Qing, Henry, Hadrien, Griffin, William L., Zheng, Jian-Ping, Satsukawa, Takako, Pearson, Norman J., O’Reilly, Suzanne Y. (2017) High- and low-Cr chromitite and dunite in a Tibetan ophiolite: evolution from mature subduction system to incipient forearc in the Neo-Tethyan Ocean. Contributions to Mineralogy and Petrology, 172 (6) doi:10.1007/s00410-017-1364-y | Journal (article/letter/editorial) | | and low‑Cr chromitite and dunite in a Tibetan ophiolite: evolution from mature subduction system to incipient...Al3+)] chromitites and dunites from the Zedang ophiolite in the Yarlung Zangbo Suture (South Tibet) have...Roeder 2001; Kamenetsky et al. 2001; Rollinson 2008; Gonzalez-Jimenez et al. 2011, 2014; Arai and Miura...Melcher et al. 1997; Ahmed and Arai 2002; Rollinson 2008; Uysal et al. 2009; Gonzalez-Jimenez et al. 2011;...2011; Morishita et al. 2011; Rollinson and Adetunji 2013; Zhou et al. 2014; Arai and Miura 2016). Integration |  | | Journal (article/letter/editorial) | | ore minerals are Cr-spinel with high Cr# (Cr/(Cr + Al) = 0.8–0.83), as well as serpentine and chlorite...inclusions are olivine (serpentine) and amphibole; phlogopite, pyroxenes, and base metal sulfides are rare...hydrous silicates: amphibole, and less often with phlogopite or chlorite. Discussed in the paper is the possible...chromitite ores; Cr-spinel; olivine; amphibole; PGM; ophiolite; ultramafic rock; Kempirsai min13020263 Academic...deposits are the largest known ones, contained in ophiolite-type complexes, and are the second-most abundant |
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