Low-Frequency Attenuation in Polycrystalline Silicates and Silicate Partial Melts

多晶硅酸盐和硅酸盐部分熔体的低频衰减

• 批准号: 0207642
• 负责人: Reid Cooper
• 金额: $ 23.19万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2004-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0207642&HistoricalAwards=false
• 关键词: Low; Frequency; Attenuation; Polycrystalline; Silicates

Reid F. Cooper, Principal InvestigatorUniversity of Wisconsin-Madison The measurement of the low-frequency attenuation behavior of polycrystalline olivine aggregates, of olivine-orthopyroxene aggregates and of olivine-based partial melts will be pursued. Specifically, the polycrystalline materials, which will have carefully engineered microstructures, will be subjected to dynamic ("sub-resonant", oscillatory loading) and quasistatic (constant loading, i.e., creep) so as to evaluate the attenuation behavior as functions of (i) temperature (1150 to 1350 degC), (ii) frequency (2x10e-4 to 1 Hz), (iii) phase volume fraction and morphology (phase percolation and phase separation/layering in the solid state; melt segregation beyond the grain scale in partial melts), and (iv) dislocation-creep sub-microstructure. The study/characterization of microstructural effects (engineered into these specimens so as to mimic deformation-induced microstructures) on seismic-frequency absorption is one key to applying seismic data to infer deformation behavior in active tectonic terranes.

威斯康星 - 麦迪逊群岛的首席研究人员Reid F. Cooper将追求多晶的橄榄石聚集体，橄榄石 - 异拷贝聚集体和橄榄石基部分熔体的低频衰减行为的测量。 Specifically, the polycrystalline materials, which will have carefully engineered microstructures, will be subjected to dynamic ("sub-resonant", oscillatory loading) and quasistatic (constant loading, i.e., creep) so as to evaluate the attenuation behavior as functions of (i) temperature (1150 to 1350 degC), (ii) frequency (2x10e-4 to 1 Hz), (iii) phase volume fraction and形态（固态中的相位渗透和相位分离/分层；部分熔体中的晶粒尺度超出晶粒范围）和（iv）脱位 - reep-creep子微结构。 微观结构效应的研究/表征（在这些标本中进行了设计，以模拟变形诱导的微观结构）对地震频率吸收是一种关键，即应用地震数据来推断活性构造式地形中的变形行为。