U-Pb Dating the Mechanical Fusion of Archean Crust to its Mantle Keel in a Cross-Section through the African Continent

U-Pb 测年非洲大陆横截面中太古代地壳与其地幔龙骨的机械融合

• 批准号: 9805210
• 负责人: Desmond Moser
• 金额: $ 9.15万
• 依托单位: University of Utah
• 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: 1999-01-01 至 2001-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9805210&HistoricalAwards=false
• 关键词: Pb; Dating; Mechanical; Fusion; Archean

9805210 Moser The problem of early crust formation in the Archean is a critical one bearing on planetary evolution and on crust-mantle relationships in what has become known as the 'tectosphere.' Because of the lack of exposure of the lower crust, there are very few places where this can be studied. However, the Kaapvaal area is one place where a major section of the crust has been tilted in the region surrounding the Vredefort impact structure. It is here that this study will focus on the relationship between the lower crust and upper mantle, focusing in particularly on the how the lower crust came to be welded to the upper mantle that now forms a strong mantle 'keel.' If successful, this study will shed light on the early evolution of the crust in South Africa, but with general applications to the origin of the lithosphere on earth and on other similar planets.

9805210莫泽太古宙早期地壳形成问题是一个关键问题，关系到地球演化和被称为“构造圈”的壳幔关系。由于缺乏下地壳的暴露，可以研究这一点的地方很少。然而，卡普瓦尔地区是一个地壳的主要部分在Vredefort Impact构造周围地区发生倾斜的地方。正是在这里，这项研究将集中于下地壳和上地幔之间的关系，特别是下地壳如何与上地幔焊接，后者现在形成了一个强大的地幔‘龙骨’。如果成功，这项研究将阐明南非地壳的早期演化，但对地球和其他类似行星的岩石圈起源也有普遍应用。