Elasticity of High Pressure Phases of Mantle Minerals

地幔矿物高压相的弹性

• 批准号: 0635651
• 负责人: Robert Liebermann
• 金额: $ 36万
• 依托单位: SUNY at Stony Brook
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-12-01 至 2012-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0635651&HistoricalAwards=false
• 关键词: Elasticity; Pressure; Phases; Mantle; Minerals

Seismological investigations yield the most precise information on the velocities of sound waves in the Earth's interior. Laboratory measurements of the sound velocities in minerals at simultaneous high pressures and temperatures enable these seismic data to be interpreted in terms of chemical composition, mineralogy and temperature. This project will include experimental determinations of elastic properties of minerals in the Earth's mantle.Over the past decade, with the support of the NSF Division of Earth Sciences, ultrasonic interferometric techniques have been developed for use in combination with multi-anvil, high-pressure apparatus and in conjunction with synchrotron X-radiation facilities at the national laboratories of the Department of Energy. This research program also takes advantage of the special opportunities for research that are provided by the multi-anvil, large-volume facilties of the Stony Brook High Pressure Laboratory and the associate analytical facilities of the Mineral Physics Institute at Stony Brook University. Some of these facilities were developed under the auspices of the NSF Science and Technology Center for High Pressure Research [CHiPR] from 1991-2002.These experiments will be conducted using high-pressure, multi-anvil apparatus, installed on the superconducting wiggler beamline at the National Synchrotron Light Source (NSLS) of the Brookhaven National Laboratory; the operation of this apparatus at NSLS is supported by the Consortium for Materials Properties Research in Earth Sciences (COMPRES). Other experiments will be performed using the multi-anvil facilities operated by GeoSoilEnviroCARS [GSECARS] at the Advanced Photon Source of the Argonne National Laboratory.Specific minerals which are currently being studied include :(1) Orthopyroxene, the second most abundant mineral in upper mantle rocks. Previous experiments have revealed anomalous elastic behavior at high pressures when this mineral transforms to the monoclinic structure. Such phase transformations in pyroxenes may help to explain discontinuities in seismic velocities observed at depths of 200-300 kilometers inside the Earth.(2) Perovskite-structure minerals with compositions CaTiO3 and CaSiO3. In mixtures of these minerals, there are transitions from orthorhombic to tetragonal symmetry which are accompanied by changes in the elastic properties.(3) Ferropericlase is the second most abundant mineral in the lower mantle of the Earth. Previous studies at high pressure and room temperature are being extended to high temperatures and pressures for comparison with seismic models in this region.

地震学调查产生有关地球内部声波速度的最精确信息。 同时高压和温度下矿物质中声速的实验室测量，使这些地震数据能够用化学成分，矿物学和温度来解释。 该项目将包括对矿物质在地球地幔中的弹性特性的实验性确定。在过去的十年中，在NSF地球科学区域的支持下，已经开发了超声波干涉技术，可与多层，高压设备结合使用，并与Synchrotron X-Radiation Lainiation in Nationals in Nationals in Nationals of Nationals interatory in National synchrotrotroties of Nationals interatory of Nationals intartorator of Nationals intartorator in National synatirator a。 该研究计划还利用了Stony Brook高压实验室的多批量大型工具以及Stony Brook University矿物质研究所的副分析设施提供的特殊研究机会。 Some of these facilities were developed under the auspices of the NSF Science and Technology Center for High Pressure Research [CHiPR] from 1991-2002.These experiments will be conducted using high-pressure, multi-anvil apparatus, installed on the superconducting wiggler beamline at the National Synchrotron Light Source (NSLS) of the Brookhaven National Laboratory; 该设备在NSLS的运行得到了地球科学材料特性研究（Compres）的材料性质研究的支持。 其他实验将使用由Geosoilenvirocars [GSecars]在Argonne National Laboratoration的高级光子源运营的多动力学设施进行。当前正在研究的特定矿物质包括：（1）Orthopyroxene，包括：（1）上层矿物质的第二大矿物矿物质。 先前的实验表明，当这种矿物转化为单斜结构时，在高压下的异常弹性行为。 辉石烯中的这种相变可能有助于解释地球内200-300公里深度的地震速度的不连续性。（2）钙钛矿结构矿物质具有Catio3和Casio3。 在这些矿物质的混合物中，从正栓到四方对称性存在过渡，并伴有弹性特性的变化。（3）二磷酸酯是地球下层中第二大最丰富的矿物。 先前在高压和室温下的研究已扩展到高温和压力，以与该区域的地震模型进行比较。