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水对Wadsleyite和Ringwoodite电导率的影响及地球动力学意义 被引量:9
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作者 黄晓葛 白武明 +1 位作者 XUYouSheng Shun-ichiroKarato 《岩石学报》 SCIE EI CAS CSCD 北大核心 2005年第6期1743-1748,共6页
在 Kawai-1000型多顶砧压机上,利用橄榄石相变人工合成地幔转换带矿物 wadsleyite 和 ringwoodite,其含水量从0.03wt%到2.0wt%变化不等。在压力14~16GPa,温度873K~1273K,通过 Mo:MoO_2固体反应控制氧逸度的条件下,利用阻抗谱分析方法... 在 Kawai-1000型多顶砧压机上,利用橄榄石相变人工合成地幔转换带矿物 wadsleyite 和 ringwoodite,其含水量从0.03wt%到2.0wt%变化不等。在压力14~16GPa,温度873K~1273K,通过 Mo:MoO_2固体反应控制氧逸度的条件下,利用阻抗谱分析方法,测量获得了这些样品的电导率。实验结果显示:wadsleyite 的电导率与 C_H^(0.66)呈正比,ringwoodite 的电导率与C_H^(0.69)呈正比,水极大地增强了样品的电导率;在我们的实验条件下,含水 wadsleyite 和 ringwoodite 样品的主要电荷载体是自由质子。另外,结合大地电磁反演获得的电导率结果和我们的实验数据,我们推断中国东北地区地幔转换带中的水含量约为0.1~0.3wt%,远远高于上地幔中的水含量,这或许表明在410km 处可能发生了部分熔融。 展开更多
关键词 电导率 地幔转换带 WADSLEYITE ringwoodite
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Preliminary Deformation Experiment of Ringwoodite at 20 GPa and 1 700 K Using a D-DIA Apparatus 被引量:1
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作者 Takaaki Kawazoe Tomohiro Ohuchi +2 位作者 Norimasa Nishiyama Yu Nishihara Tetsuo Irifune 《Journal of Earth Science》 SCIE CAS CSCD 2010年第5期517-522,共6页
A deformation experiment of ringwoodite with a strain of 9% was achieved at 20 GPa and 1 700 K and at a strain rate of 3×10^-5 s^-1 using a deformation-DIA (D-DIA) apparatus and a multi-anvil 6-6 (MA 6-6) ass... A deformation experiment of ringwoodite with a strain of 9% was achieved at 20 GPa and 1 700 K and at a strain rate of 3×10^-5 s^-1 using a deformation-DIA (D-DIA) apparatus and a multi-anvil 6-6 (MA 6-6) assembly. The crystallographic orientations of the deformed sample were successfully analyzed by the electron backscatter diffraction (EBSD) method, although any notable latticepreferred orientation (LPO) was not observed presumably due to the insufficient strain in the present experiment. In this study, the deformation experiment on ringwoodite succeeded at P-T conditions consistent with the lower part of the mantle transition zone and at a controlled strain rate for the first time. The present study extended the pressure range of deformation experiments in the D-DIA apparatus from 16 GPa in our earlier study to 20 GPa at 1 700 K. The successful extension of the pressure range demonstrates potential importance of the D-DIA apparatus in studying rheological properties of minerals under the P-T conditions of the whole mantle transition zone. 展开更多
关键词 ringwoodite mantle transition zone RHEOLOGY VISCOSITY mantle dynamics.
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First Terrestrial Occurrence of Ringwoodite
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作者 王尔康 万玉秋 +2 位作者 孔佑华 邵玉英 张文兰 《Chinese Science Bulletin》 SCIE EI CAS 1993年第19期1651-1655,共5页
Several of the known over 3000 minerals possess great typomorphic implication and experienced twists and turns of their discovery. Ringwoodite is the most outstanding of them. In 1931, Goldshmidt suggested that the cr... Several of the known over 3000 minerals possess great typomorphic implication and experienced twists and turns of their discovery. Ringwoodite is the most outstanding of them. In 1931, Goldshmidt suggested that the crystal structure of Mg<sub>2</sub>GeO<sub>4</sub> could show two polymorphs for olivine and spinel. Based on this, in 1936, J. D. Bernal put forward his bold assumption that the increase of seismic velocity in mantle is caused by 展开更多
关键词 ringwoodite extraterrestrial microspherules COSMIC DUST granite.
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Hydration effects on crystal structures and equations of state for silicate minerals in the subducting slabs and mantle transition zone 被引量:2
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作者 YE Yu 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第4期707-719,共13页
There are potentially huge amounts of water stored in Earth's mantle, and the water solubilities in the silicate minerals range from tens to thousands of part per minion(ppm, part per million). Exploring water in ... There are potentially huge amounts of water stored in Earth's mantle, and the water solubilities in the silicate minerals range from tens to thousands of part per minion(ppm, part per million). Exploring water in the mantle has attracted much attention from the societies of mineralogy and geophysics in recent years. In the subducting slab, serpentine breaks down at high temperature, generating a series of dense hydrous magnesium silicate(DHMS) phases, such as phase A, chondrodite, clinohumite, etc. These phases may serve as carriers of water as hydroxyl into the upper mantle and the mantle transition zone(MTZ). On the other hand, wadsleyite and ringwoodite, polymorphs of olivine, are most the abundant minerals in the MTZ, and able to absorb significant amount of water(up to about 3 wt.% H_2O). Hence, the MTZ becomes a very important layer for water storage in the mantle, and hydration plays important roles in physics and chemistry of the MTZ. In this paper, we will discuss two aspects of hydrous silicate minerals:(1) crystal structures and(2) equations of state(Eo Ss). 展开更多
关键词 Hydrous silicate mineral Crystal structure Equation of state(Eo S) Mantle transition zone(MTZ) WADSLEYITE ringwoodite
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陨石中林伍德石的形成条件对寻找地球产状林伍德石的启示 被引量:2
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作者 陈鸣 《地学前缘》 EI CAS CSCD 北大核心 2005年第1期23-27,共5页
橄榄石高压多形林伍德石被认为是地幔过渡带的主要矿物。天然产状林伍德石主要在发生强烈冲击变质的球粒陨石冲击脉体中出现。目前还没有在地球岩石中发现林伍德石的报告。陨石冲击脉体的温度压力历史和矿物组合特征研究表明,林伍德石... 橄榄石高压多形林伍德石被认为是地幔过渡带的主要矿物。天然产状林伍德石主要在发生强烈冲击变质的球粒陨石冲击脉体中出现。目前还没有在地球岩石中发现林伍德石的报告。陨石冲击脉体的温度压力历史和矿物组合特征研究表明,林伍德石形成后,高压下淬火是使林伍德石不发生退变作用的重要条件。陨石中有利于林伍德石保存的淬火时间仅为数秒到十多秒。在地球上任何地质事件中,均难以实现在如此短的时间内使位于地幔过渡带的林伍德石被带往地球表层。寻找地球产状的林伍德石,关键是要在岩石和矿物中存在有利于林伍德石保存的条件,特别是当这些岩石和矿物仍处于高温的环境时。 展开更多
关键词 林伍德石 橄榄石 冲击脉体 陨石 地幔
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The Time Events and the Poetics of Care for the Oceans
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作者 Emily ShuHui Tsai 《Journal of Philosophy Study》 2019年第9期544-552,共9页
The images of the oceans often inspire us to take a poetic lift of the spirit for an escape from the daily boredom or troubles related to the social restriction based on the ideological hierarchy.On the other hand,how... The images of the oceans often inspire us to take a poetic lift of the spirit for an escape from the daily boredom or troubles related to the social restriction based on the ideological hierarchy.On the other hand,however,the collective human desires have no good ethics to discipline the insatiable enjoyment that has obviously damaged the environment and polluted the oceans.In this short paper,I focus on the concepts of the time event,Aion and Chronos,with the three poems related to the images of the oceans written by a Taiwan Residents poet,Hui Tong;I also try to understand how the origin of the water on our Earth comes from.In fact,our Earth has the“liquid”oceans on the surface and also the hidden“solid”oceans,the blue crystal rocks called ringwoodite,within Earth’s mantle.The oceans absorb heat and the tiny ocean plants called phytoplankton drifting with the oceanic currents produce oxygen through photosynthesis for the human health as well.But the contemporary environmental problem is that the chronic damages of the biodiversity by the human collective desires have affected the oceans to become seriously polluted.Therefore,we have the feelings of ambivalence toward the images of the oceans:tranquility,transience,creativity,oblivion or corruption and hostility for the human bad habits. 展开更多
关键词 the TIME EVENTS the virtual SINGULARITIES phantasm OCEAN ringwoodite
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铁尖晶橄榄石的穆斯堡尔谱研究
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作者 傅平秋 李哲 《矿物学报》 CAS CSCD 北大核心 1996年第2期147-151,共5页
本文使用穆斯堡尔效应研究了在高温高压下合成的铁橄榄石和铁尖晶橄榄石。298K温度下铁橄榄石的穆斯堡尔谱由一组双峰组成,它被指派给Fe2+(M1,M2)离子。298K温度下铁尖晶橄榄石的穆斯堡尔谱由三组双峰组成,其中两组双峰指派给八... 本文使用穆斯堡尔效应研究了在高温高压下合成的铁橄榄石和铁尖晶橄榄石。298K温度下铁橄榄石的穆斯堡尔谱由一组双峰组成,它被指派给Fe2+(M1,M2)离子。298K温度下铁尖晶橄榄石的穆斯堡尔谱由三组双峰组成,其中两组双峰指派给八面体位置B上的Fe2+,另一组双峰归结为四面体位置A上的Fe3+,两组Fe2+双峰的同质异能位移近似相等而四极分裂不同,Si原子在八面体位置上的占有率为6%~10%。铁尖晶微榄石的结构化学式可写为,其中x=0.12~0.20。随着合成样品压力的增加,x值略有增大,但x值随合成样品温度的升高基本保持不变。此外,根据Fe2+同质异能位移与平均键长之间的关系,得到铁橄榄石和铁尖晶三中的平均键长Fe-O和(Fe,Si)-O分别为d=0.2143um和d=0.2071~0.2085nm。 展开更多
关键词 穆斯堡尔效应 铁尖晶橄榄石 橄榄石
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