Whole Mantle Electrical Conductivity & the Velocity Field ofUpper Core-Constraints from Applied Mantle Filter Theory, GDS, and improvements in the Global Geomagnetic Database

全地幔电导率

• 批准号: 8816998
• 负责人: Adam Schultz
• 金额: $ 21.32万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-07-01 至 1994-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8816998&HistoricalAwards=false
• 关键词: Whole; Mantle; Electrical; Conductivity; &amp

Initial results of deep mantle electrical conductivity studies underway suggest that a localized jump in electrical conductivity is present at midmantle depths, with a peak in the conductivity gradient roughly coincident with the 670 km seismic discontinuity. The PI will obtain higher resolution models of the electrical conductivity of the whole mantle. This involves calculating equivalent scalar magnetotelluric impedance functions from ratios of magnetic field Fourier coefficients. The transformation of spectral ratios into impedances is made possible by knowledge of the magnetic field source structure. He will apply concepts of robust statistical parameter estimation to the problem of spherical harmonic analysis.

正在进行的深部地幔电导率研究的初步结果表明，中地幔深处存在电导率的局部跳跃，电导率梯度的峰值大致与 670 km 地震不连续性一致。 PI 将获得整个地幔电导率的更高分辨率模型。 这涉及根据磁场傅里叶系数的比率计算等效标量大地电磁阻抗函数。 通过了解磁场源结构，可以将谱比转换为阻抗。 他将把鲁棒统计参数估计的概念应用于球谐分析问题。