CSEDI Collaborative Research: Investigation of Thermo-Chemical Heterogeneity in the Deep Mantle

CSEDI合作研究：地幔深部热化学非均质性研究

• 批准号: 9905779
• 负责人: Bradford Hager
• 金额: --
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-01 至 2002-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9905779&HistoricalAwards=false
• 关键词: CSEDI; Collaborative; Research; Investigation; Thermo

9905779Hager The investigators propose to carry out a collaborative, multidisciplinary study of proposed compositional stratification in the lowermost ~1200 kilometers of Earth's mantle. The investigators hypothesize that the existence of compositionally distinct regions can reconcile observational constraints from seismological, geochemical, heat flow, and other geophysical observations into a unified model of the dynamics of the deep mantle. Preliminary numerical models imply that a hot abyssal layer of material that is intrinsically about 5% more dense than the overlying mantle is dynamically stable, though its surface develops hundreds of kilometers of topography. The proposed work uses numerical models of thermochemical convection in 2-D and 3-D, seismological modeling of structure in the deep mantle, and calculations of model seismic velocities and other geophysical observables resulting from the numerical experiments to test this idea.

9905779Hager 研究人员提议对地幔最下部约 1200 公里的成分分层进行协作、多学科研究。 研究人员假设，成分不同区域的存在可以将地震学、地球化学、热流和其他地球物理观测的观测约束调和成一个统一的深部地幔动力学模型。初步的数值模型表明，热深海物质层的密度比上覆地幔高出约 5%，尽管其表面形成了数百公里的地形，但它是动态稳定的。 所提出的工作使用 2 维和 3 维热化学对流数值模型、深部地幔结构的地震学建模以及模型地震速度和数值实验产生的其他地球物理观测值的计算来检验这一想法。