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dunite n.【地質學;地理學】純橄欖巖。

duniwassal

Electrical conductivities of quartz , olivine , dunite , iherzolite , pyroxenite , and megaaugite were measured by virtue of the new system ; whereas , the electrical conductivity of gabbro was measured by means of the old one . an interesting outgrowth of the present study is the measurement of the complex impedance of a series of quartz plates with different orientations 石英(人造水晶) 、橄欖石、純橄欖巖、輝石巖、二輝橄欖巖、巨晶輝石的電導率測量是在新的測量系統下獲得的,而輝長巖的電導率測量是基于lcr儀為測量儀器的測試系統下獲得的。

Secondly , based on the microbeam analytical technique , on the one hand , through investigating the characteristic of major elements in the mantle minerals the author acquired the static information from mantle ; on the other hand , through multi - point analysis of a part of the minerals from mantle , the auther got dynamic information from mantle . finally , generalizating the fruits of this study and predecessors , the autor holds that the constituents of lithospheric mantle possibly includes spinel lherzolites , clinopyroxenites , websterite , dunite , harzburgites , garnet lherzite , phlogopite lherzite , eclogites , clinopyroxene megacrysts ; compared with east china and north china platform , the research field mantle shows the characteristics of higher degree of partial melting processes and more depleted mantle ; the . upper mantle beneath north hetian area is heterogeneous , with a tendency of deficit in a12o3 and lree from kaliyang in west hetian to the river basin of kalakshi river and yulongkashi river ; the subduction of the crust beneath north hetian has ever occurred in geological history and caused the mixing of mantle - crust ; the depth of the origination of basaltic magmas beneath north hetian exceeds 73km ; the thickness of the lithosphere beneath the research area amounts to 204 . 9km ; the mantle beneath north hetian has geological condtions for forming diamond deposits 最后,綜合本區幔源礦物和地幔巖石的特征以及地球物理資料,得出如下結論:本區上地幔的物質組成有尖晶石二輝橄欖巖、二輝巖、單斜輝石巖、純橄欖巖、方輝橄欖巖、石榴石二輝橄欖巖、金云母二輝橄欖巖、榴輝巖;與中國東部以及華北地臺上地幔相比,研究區上地幔具有富集主元素中相容元素和虧損其中的不相容元素的特征,局部熔融程度較高;上地幔存在橫向和縱向的不均一性,從西部的克里陽到喀拉喀什河和玉龍喀什河流域, al和lree富集程度呈下降趨勢,不同來源的相同礦物中主元素的含量差異較大;地質歷史時期這里可能發生過地殼俯沖并產生殼幔混合作用;玄武巖漿的起源深度73km ;從幔源重砂礦物的溫壓估算結果,可以推斷出巖石圈厚度可達204 . 9km ;綜合巖石圈物質組成特征、巖石圈熱狀態、地幔溫壓狀態、氧逸度以及幔源巖石和幔源礦物的化學成分,認為研究區具備了金剛石成礦地幔地質條件。

The complex electrical properties of dunite were measured over the frequency range from 0 . 1 - 106hz , at 1 - 3 gpa and 1282 - 1544k , and at the fo2 of mo - moo2 . complex plane plots show separate effects of grain interior and grain boundary conductivity 對顆粒邊界的電導率研究表明,顆粒邊界的電導率高于顆粒內部的電導率,總電導率則小于顆粒內部和顆粒邊界的電導率,顆粒邊界并沒有增強總電導率。

The ophiolite massifs are composed of mantle peridotite that is mainly harzburgite and dunite , and lacked of crust magmatite within the typical ophiolite suite 摘要該蛇綠巖帶的巖體由地幔橄欖巖組成,主要巖石類型是方輝橄欖巖和純橄欖巖,缺少典型蛇綠巖剖面中的洋殼單元。