Elements circulation within the earth deduced from the mineralogical and petrological studies of eclogites

从榴辉岩的矿物学和岩石学研究中推断出地球内部的元素循环

• 批准号: 14540448
• 负责人: ENAMI Masaki
• 金额: $ 2.3万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14540448/
• 关键词: metamorphism; eclogite; material recycling; metamorphic fluid; subduction zone; garnet-peridotite; Sr-isotope; rock-forming minerals; 珪灰石; CO2分圧; P-T経路; Dissakisite; Hydroxylian pseudorutile

The following representative conclusions were drawn from our detailed petrological and mineralogical works on high-pressure and ultrahigh-pressure metamorphic rocks.(1)Dissakisite is a Mg-derivative substitution of allanite. Cr203-dissakisite occurs in a garnet-lherzolite from the Su-Lu ultrahigh-pressure metamorphic belt, China. This mineral is an important reservoir of Sr and REE hi subducting ultramafic rocks, and plays a significant role in the material interaction between the crust and upper mantle.(2)Sr-isotopic analyses were done on eclogites and their constituent minerals from the Su-Lu ultrahigh-pressure metamorphic belt, China. The Sr-isotopic zonal structure of zoisite and the estimated 87Sr/86Sr initial ratios clearly indicate widespread metamorphic fluid migration and isotopic homogenization during exhumation stage of the ultrahigh-pressure metamorphic rocks.(3)Garnet-peridotites from the Bessi area in the Sanbagawa metamorphic belt record the P-T path with early stage of low-temperature hydrous reaction and subsequent stage of nearly adiabatic pressure increase up to 3-4 GPa, showing subduction of wedge mantle peridotites down to 100 km in depth.(4)The eclogite and non-eclogite units are proposed in the Sanbagawa metamorphic belt mainly based upon the tectonic research. Large pressure gap of 1 GPa at peak metamorphic stage between the two units was confirmed by the phase analyses of chloritoid-bearing metamorphic rocks. This fact clearly indicates the presence of tectonic discontinuity between the two units and petrologically supports the idea of large-scale nappe structure hi the Sanbagawa belt.

我们通过对高压和超高压变质岩进行详细的岩石学和矿物学研究，得出了以下代表性结论：(1)三钠镁石是钠长石的镁衍生物替代物。 Cr203-二菱锰矿产于中国苏鲁超高压变质带的石榴石二辉橄榄岩中。该矿物是俯冲超镁铁岩中重要的锶和稀土元素储集层，在地壳与上地幔的物质相互作用中发挥着重要作用。(2)对中国苏鲁超高压变质带榴辉岩及其组成矿物进行了锶同位素分析。黝帘石的Sr同位素带状结构和估计的87Sr/86Sr初始比值清楚地表明了超高压变质岩折返阶段广泛的变质流体运移和同位素均一化。(3)三八川变质带Bessi地区的石榴石橄榄岩记录了早期的P-T路径。 低温含水反应及随后阶段的近绝热压力增加至3-4 GPa，显示出楔形地幔橄榄岩俯冲至100 km深度。(4)主要根据构造研究，提出了三八川变质带的榴辉岩和非榴辉岩单元。含绿泥石变质岩的物相分析证实了两个单元之间在变质峰阶段存在 1 GPa 的大压力差距。这一事实清楚地表明两个单元之间存在构造不连续性，并且在岩石学上支持了三波川带大规模推覆构造的观点。

项目成果

Hydroxylian pscudorutilc in an adamellite from the Nkambe area, Cameroon.

产自喀麦隆 Nkambe 地区的二钠长石中的羟基假石榴石。

• 发表时间: 2003
• 期刊: Mineralogical Magazine 67
• 作者: Tetsopgang;S.;Koyanagi;J.;Enami;M.;Kihara;K.
• 通讯作者: K.

Chromion dissakisite-(Ce) in a garnet lherzolite from the Chinese Su-Lu UHP metamorphic terrane : Implications for Cr incorporation in epidotc-group minerals and recycling of REE into the Earth's mantle.

中国苏鲁超高压变质地体石榴石二辉橄榄岩中的铬离子二钠锰矿（Ce）：对绿帘石族矿物中铬的掺入以及稀土元素再循环到地幔中的影响。

• 发表时间: 2003
• 期刊: American Mineralogist 88
• 作者: Yang;J.J.;Enami;M.
• 通讯作者: M.

Chemical Diversity of the Ueno Basalts, Central Japan: Identification of Mantle and Crustal Contributions to Arc Basalts

• DOI: 10.1093/petrology/43.10.1923
• 发表时间: 2002-10
• 期刊: Journal of Petrology
• 影响因子: 3.9
• 作者: J. Kimura;W. Manton;C. Sun;S. Iizumi;Takeyoshi Yoshida;R. Stern

Aoya, M., Uehara, S., Matsumoto, M., Wallis, S.R., Enami, M.: "Subduction-stage P-T path of eclogite from the Sambagawa belt : prophetic record for oceanic-ridge subduction"Geology. 31. 1045-1048 (2003)

Aoya, M.、Uehara, S.、Matsumoto, M.、Wallis, S.R.、Enami, M.：“三波川带榴辉岩的俯冲阶段 P-T 路径：大洋脊俯冲的预言记录”地质学。

Hydroxylian pseudorutile in an adamellite from the Nkambe area, Cameroon

喀麦隆 Nkambe 地区的二菱锰矿中的羟基假金红石

• 发表时间: 2003
• 期刊: Mineralogical Magazine 67
• 作者: Tetsopgang;S.;Koyanagi;J.;Enami;M.;Kihara;K.
• 通讯作者: K.