| | Journal (article/letter/editorial) | 0016-7037(95)00086-O Thermal and shock metamorphism of the Tenham chondrite: A TEM examination FALKO LANCENHORST...early episode of the solar system, the L6 chondrite Tenham has been affected by intense thermal metamorphism...phases majorite and ringwoodite, the L6 chondrite Tenham is an instructive example for strong shock metamorphism...signature of the silicates occurring in the bulk of Tenham. Plagioclase is either pervaded by thin (200 nm)... A low dislocation density (clinoenstatite lamellae have been detected in orthoenstatite | | | Journal (article/letter/editorial) | new silicate mineral of the ilmenite group in the Tenham chondrite NAOTAKA TOMIOKA* AND KIYOSHI FUJINO...shock-metamorphosed Tenham chondrite. It occurs as aggregates adjacent to clinoenstatite in fragments within...formula to be (Mg0.79Fe0.21)SiO3,the same as for clinoenstatite. Selected-area electron diffraction (SAED)...pressure and temperature generated by shock events in Tenham are estimated to be 22 GPa ,Pmax , 26 GPa and Tmax...a natural silicate perovskite phase in the Tenham meteorite was found. These high-pressure silicate minerals | | | Journal (article/letter/editorial) | transformation in a shock-induced melt vein of Tenham L6 chondrite Zhidong Xie ⁎, Thomas G. Sharp School...fragments entrained in a 580-μm-wide melt vein of the Tenham L6 chondrite were investigated using fieldemission...phases include ringwoodite, low-Ca majorite, clinoenstatite, hollandite-structured plagioclase and Ca-rich...suggest that most solid-state transformations in the Tenham are reconstructive. The transformation of olivine...ringwoodite lamellae; growth rate; Tenham 1. Introduction Tenham is a highly shocked L6 chondrite with | | | Journal (article/letter/editorial) | 657 − 8501, Japan The shear mechanism in the clinoenstatite (space group C2/c) − akimotoite (space group...translation vector, [001] on the (100) plane of clinoenstatite, dissociates into a 1/3[001] + 1/6[011] + 1/3[001]...overpressure from the hypothetical equilibrium clinoenstatite − akimotoite phase boundary would be high,...in shocked meteorites. Keywords: Akimotoite, Clinoenstatite, High − pressure transition, Shear mechanism...composition has been found in a shocked chondritic meteorite (Tomioka and Fujino, 1997, 1999). This sowed intergrowths | | Guo, Zhuang, Li, Yang, Liu, Shen, Xu, Huifang, Xie, Zhidong, Li, Shijie, Li, Xiongyao, Lin, Yangting, Coulson, Ian M., Zhang, Mingming (2020) Discovery of nanophase iron particles and high pressure clinoenstatite in a heavily shocked ordinary chondrite: Implications for the decomposition of pyroxene. Geochimica et Cosmochimica Acta, 272. 276-286 doi:10.1016/j.gca.2019.10.036 | Journal (article/letter/editorial) | nanophase iron particles and high pressure clinoenstatite in a heavily shocked ordinary chondrite:implications...nanophase iron particles and high pressure clinoenstatite in a heavily shocked ordinary chondrite:implications...nanophase iron particles and high pressure clinoenstatite in a heavily shocked ordinary chondrite : implications...association of np-Fe0, highly defective high pressure clinoenstatite (HP-CEn), silica glass, as well as vesicles...glass selvage within the shock melt vein in this meteorite suggests that these phases formed as the result | | Xie, Z., Sharp, T. G., Leinenweber, K., DeCarli, P. S., Dera, P. (2011) A new mineral with an olivine structure and pyroxene composition in the shock-induced melt veins of Tenham L6 chondrite. American Mineralogist, 96 (2) 430-436 doi:10.2138/am.2011.3437 | Journal (article/letter/editorial) | composition in the shock-induced melt veins of Tenham L6 chondrite Zhidong Xie,1,* Thomas g. sharp,2...that occurs in shock-induced melt veins of the Tenham L6 chondrite. The new mineral, identified by transmission...the deep upper mantle. Keywords: Shock-induced, Tenham, olivine, melt vein inTroduCTion Impact metamorphism...those synthesized in high-pressure experiments. The Tenham L6 chondrite was strongly shocked to shock stage...Z. Xie et al. 2006a). The crystal sizes in the Tenham melt veins range from several micrometers down | | | Journal (article/letter/editorial) | minerals provide clues about the impact events of meteorite parent bodies, including their size and mutual...in Arizona, which was the product of an iron meteorite INTRODUCTION The Earth’s crust and upper mantle...ion milling and ultramicrotomy. In the case of meteorite samples, the target particles for TEM observations...ringwoodite, was discovered in the shock vein of the Tenham chondrite (L6; Binns et al. 1969). Ringwoodite...spinel was discovered in the shock vein of a meteorite, the Umbarger chondrite (L6; Xie et al. 2002b) | | | Journal (article/letter/editorial) | Electron Petrography of Shock-Produced Veins in the Tenham Chondrite G.D. Price, A. Putnis, and S. O. Agrell...in, and adjacent to the black veins of the Tenham meteorite reveals that the minerals have undergone varying...shock. The orthopyroxenes of the bulk of the meteorite have been transformed to clinopyroxenes in areas...the release of pressure. The olivines of the meteorite are also deformed, and some have been transformed...the fi-phase polymorph. Introduction The Tenham meteorite is a white olivine-hypersthene chondrite, | | | Journal (article/letter/editorial) | pressure in some cases. Thick melt veins in the Tenham L6 chondrite contain majorite and magnesiowüstite...However, very thin melt veins (5–30 μm wide) in Tenham contain glass, olivine, clinopyroxene, and ringwoodite...Ramsdorf and Nakhon Pathon contain olivine and clinoenstatite, indicating pressure of less than 15 GPa. Melt...(Chen et al. 1996), Acfer 040 (Sharp et al. 1997), Tenham (Tomioka and Fujino 1997; Xie et al. 2006), Umbarger...(Table 1), were obtained from the Center for Meteorite Studies at Arizona State University for investigation | | | Journal (article/letter/editorial) | source acting in the (100) planes (Chondrite L6 Tenham - TEM bright field, g = 002). 257 Fig. 6. Amorphous...al., 1995; Leroux et al., 1997). This ortho-clinoenstatite inversion is generated by the motion in the...along a* thicknesses proportional to 0.9 nm clinoenstatite unit cell, while the (100) dspacing is 1.8...High resolution micrograph of thin lamellae of clinoenstatite (0.9 nm fringes). 1.8 nm repeats correspond...characteristics of shock-induced microstructures in the two meteorite major phases, kamacite (bcc, Ni-poor) and taenite | | | Journal (article/letter/editorial) | identification has elucidated many aspects of meteorite formation. Of particular interest are five phosphate...calcium- and aluminum-rich silicates in the Allende meteorite, a Type 1II carbonaceous chondrite which fell...(Mason, 1962), when I wrote an account of the meteorite minerals then recognized, see Table 1, the list...accessory in some irons In Coorara and Tenham chondrites In Coorara and Tenham chondrites Accessory in Allende...Dodd (1971) 1. Originally reported in the Abee meteorite by Dawson et al. (1960), but later identified | | Ozawa, Shin, Ohtani, Eiji, Miyahara, Masaaki, Suzuki, Akio, Kimura, Makoto, Ito, Yoshinori (2009) Transformation textures, mechanisms of formation of high-pressure minerals in shock melt veins of L6 chondrites, and pressure-temperature conditions of the shock events. Meteoritics & Planetary Science, 44 (11) 1771-1786 doi:10.1111/j.1945-5100.2009.tb01206.x | Journal (article/letter/editorial) | ringwoodite, which has been described from this meteorite in a previous report (Grossman 1999). Jadeite...morphologies of akimotoite coexisting with clinoenstatite. One is granular-shaped, and the other is columnar-shaped...crystallographic relationship with the adjacent clinoenstatite, whereas the latter akimotoite (Ak) exhibits...exhibits a topotaxial relationship with clinoenstatite (Cen) of (100)Cen // (0001)Ak, (010)Cen // (10–10)Ak...akimotoite with a topotaxial relationship to clinoenstatite, Tomioka (2007) proposed a shear mechanism | | | Journal (article/letter/editorial) | it is important to investigate a variety of meteorite samples with different preshock conditions and...to better understand the correlation between meteorite shock features and planetary impact conditions...the impact velocity and projectile size on the meteorite parent body. Ohtani et al. (2004) and DeCarli...common. Raman spectroscopy shows that they are clinoenstatite and diopside (Fig. 2). No evidence for pyroxene...relationship. d) Type LP matrix contains predominantly clinoenstatite. e) An elongated wadsleyite crystal shows a | | Imae, Naoya, Kimura, Makoto, Yamaguchi, Akira, Kojima, Hideyasu (2019) Primordial, thermal, and shock features of ordinary chondrites: Emulating bulk X‐ray diffraction using in‐plane rotation of polished thin sections. Meteoritics & Planetary Science, 54 (4) 919-937 doi:10.1111/maps.13257 | Journal (article/letter/editorial) | YAMAGUCHI 1,2 , and Hideyasu KOJIMA1 1 Antarctic Meteorite Research Center, National Institute of Polar Research...metamorphic sequence from 3 to 6, while that of clinoenstatite (Cen) 22 1 is inversely correlated. The shock...is stable at high pressure for shock stage S6 (Tenham and NWA 4719). The shock melted LL chondrite is...stable under low pressure conditions. They are clinoenstatite (Cen) with the space group of P21/c and orthoenstatite...in Nantan iron meteorite), and Fe-Ni metals (cut saw of the Mundravilla iron meteorite). In-plane rotation | | | Journal (article/letter/editorial) | development of shocked), weak mosaicism; S5 (strongly clinoenstatite lamellae parallel to ( 100) ; S4 (moderately...Johnson Space Center, provided by the Antarctic Meteorite Working Group; sections labelled Y are from the...E4-5. The moderate recrystallization of this meteorite seems more consistent with petrologic type 5;...radial pyroxene chondrules and rare sinoite; the meteorite appears recrystallized, not melted. Although nearly...abundance ratio characteristic of EH chondrites. The meteorite contains niningerite (characteristic of EH) and | | | Journal (article/letter/editorial) | the clues to understand the impact events of meteorite parent bodies, but also insights on the structure...Mg2SiO4Fe2SiO4 組成の相 平衡図を示す。スピネル構造を持つ(Mg, Fe)2SiO4 は 1969 年に Tenham コンドライト(L6)の衝撃熔融脈(ショックベ イン)から発見され,リングウッダイト(ringwoodite)と命...名された(Binns et al., 1969)。変形スピネル構造を持つ (Mg, Fe)2SiO4 も,同じく Tenham 中のショックベインか ら発見された(Putnis and Price, 1979)。その後,Peace...(Mg, Fe)SiO3perovskite (MgPv) in the Martian meteorite DaG 735 (Miyahara et al., 2011a). Two diŠerent...Gasprik, 1990). LowT Cen, low-temperature clinoenstatite; Oen, orthoenstatite; Pen, protoenstatite; | | | Journal (article/letter/editorial) | polymorphs in shock-induced melt veins in the meteorite and discusses their implication to the high pressure... and vitrified perovskite were observed in the Tenham L6 chondrite (Tomioka & Fujino, 1997, 1999; Xie...Sample and analytical methods The Sixiangkou meteorite fell on August 15, 1989, in Sixiangkou Town of...akimotoite is similar to akimotoite reported in Tenham (En78Fs21Wo1: Tomioka & Fujino, 1997) and Yamato...chondrites (Acfer 040, Umbarger, Yamato 791384, Tenham) (Sharp et al., 1997; Tomioka & Fujino, 1997, 1999; | | | Journal (article/letter/editorial) | applied to polished thin sections and whole-rock meteorite samples. Three frequently observed orthoenstatite...(EL6) S2, Elephant Moraine (EET) 87746 (EH3) S3, Meteorite Hills (MET) 00783 (EH4) S4, EET 96135 (EH4–5)...81021, EL6; Elephant Moraine (EET) 87746, EH3; Meteorite Hills (MET) 00783, EH4; EET 96135, EH5; Lewis...irregular fractures, some planar fractures Clinoenstatite lamellae on (100), undulose extinction, irregular...= Allan Hills; EET = Elephant Moraine; MET = Meteorite Hills; LEW = Lewis Cliff; QUE = Queen Alexandra | | | Journal (article/letter/editorial) | also believed to occur in a shock-metamorphosed meteorite (Tomioka and Fujino 1997, 1999). These transformations...the texture observed in the shock-metamorphosed meteorite Akimotoite, Mg0:78±0:79 Fe0:22±0:21 SiO3 ilmenite...ilmenite, which was found in the shocked meteorite, shows the following characteristics (Tomioka and Fujino...ilmenite occurs as aggregates adjacent to low-clinoenstatite (P21/c). The columnar (less than 1.4 lm)-type...and 1010Ak == 010LCEN with adjacent low-clinoenstatite (Ak: akimotoite, LCEN: lowclinoenstatite). | | | Journal (article/letter/editorial) | L6 chondrite was obtained from the Center for Meteorite Studies at Arizona State University (ASU sample...and Tenham (Tomioka et al. 2000; Sharp et al. 2000) L6-S6 chondrites and in the martian meteorite Zagami...patterns, similar to those seen in ringwoodites from Tenham and Sixiangkou chondrites (Price TEM Observations...other enstatite polymorphs (orthoenstatite, clinoenstatite, majorite, and MgSiO3perovskite). Multiple...Horiuchi et al. [1982]) and those of akimotoite in Tenham chondrite (a = 0.478 ± 0.005, c = 1.36 ± 0.01 nm | | | Journal (article/letter/editorial) | 2017). In 2008, Dera et al. discovered that the meteorite mineral allabogdanite, Fe2P, is the result of...Recently stishovite was reported from a lunar meteorite (Kaneko et al. 2015). Presence of stishovite in...for the peak shock pressures that the Shergotty meteorite had experienced prior ejection from Mars (Fritz...pressures of the Shergotty meteorite. Thus, type seifertite in the Shergotty meteorite has probably formed from...disorder, in TEM studies of a highly shocked meteorite but this phase may be identical, or similar, to | | | Journal (article/letter/editorial) | different shock levels. MATERIALS AND METHODS Meteorite Selection Eight meteorites were selected for this...images of these meteorites are shown in Fig. 1. Meteorite Descriptions LaPaz Icefield (LAP) 02225 is an...enstatite and albite endmember, respectively, and the meteorite contains 3 wt% of metal (Russell et al. 2004)...planar fractures, undulose extinction, and clinoenstatite lamellae (Izawa et al. 2011); these petrologic...The enstatite grains have mosaic extinction, clinoenstatite lamellae, and twinning (Izawa et al. 2011) | | | Journal (article/letter/editorial) | olivine. Natural high-pressure phases in Martian meteorite allow to constrain phase transitions taking place...ringwoodite was discovered more than 40 yr ago in the Tenham L6 chondrite (Binns et al., 1969). Meanwhile ringwoodite...al., 2010) and in lithology A of the Martian meteorite Elephant Moraine (EET) A79001 (Walton, 2013)....totaling 1619 g (Folco and Franchi, 2000). The meteorite is part of a strewn field in which so far eight...symplectites, and solidified trapped melt. The meteorite is severely weathered containing abundant phyllosilicates | | Zedgenizov, Dmitry, Kagi, Hirioyuki, Ohtani, Eiji, Tsujimori, Tatsuki, Komatsu, Kazuki (2020) Retrograde phases of former bridgmanite inclusions in superdeep diamonds. Lithos, 370. 105659pp. doi:10.1016/j.lithos.2020.105659 | Journal (article/letter/editorial) | kimberlite pipe (South Africa) and Orroroo dyke (South Australia) (Scott Smith et al., 1984; Moore et al., 1986)...placer deposits from the Orroroo area in South Australia (Tappert et al. 2009). In this study, single-phase...appearance of lines at 369 and 431 cm-1 indicating clinoenstatite (Ulmer and Stadler, 2001) were ro observed...Extended Abstracts, Perth: Geological Society of Australia Abstracts, vol. 16, pp. 409411. Muir, J.M.R.,... K.J., 1984. Kimberlites near Orroroo, South Australia. In: Kornprobst, J. (Ed.), Kimberlites I: Kimberlites | | Ruzicka, Alex M., Hutson, Melinda, Friedrich, Jon M., Rivers, Mark L., Weisberg, Michael K., Ebel, Denton S., Ziegler, Karen, Rumble, Douglas, Dolan, Alyssa A. (2017) Petrogenesis of Miller Range 07273, a new type of anomalous melt breccia: Implications for impact effects on the H chondrite asteroid. Meteoritics & Planetary Science, 52 (9) 1963-1990 doi:10.1111/maps.12901 | Journal (article/letter/editorial) | RUMBLE III7, and Alyssa A. DOLAN2,8 1 Cascadia Meteorite Laboratory, Department of Geology, Portland State...coarse metal, a matrix composed chiefly of clinoenstatite and omphacitic pigeonite, and troilite veining...closely resembles H and L chondrites than any other meteorite class. Fig. 1. d18O versus Δ17O (=d17O 0.52...chondrites, indicating an H chondrite affinity for the meteorite. The MIL troilite content is somewhat low compared...low-Ca pyroxene; opx = orthopyroxene; clen = clinoenstatite; troi or T = troilite, met or M = metal; ma |
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