Fracture Zone-Hot Spot Interactions Along the Marquesas Fracture Zone

沿马克萨斯断裂带的断裂带-热点相互作用

• 批准号: 9012949
• 负责人: Marcia McNutt
• 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: 1991
• 资助国家: 美国
• 起止时间: 1991-03-01 至 1993-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9012949&HistoricalAwards=false
• 关键词: Fracture; Zone; Hot; Spot; Interactions

During a 1987 expedition to the Marquesas Island chain, the principal investigators mapped part of a high ridge that lies at the intersection of the Marquesas swell with the Marquesas fracture zone. They concluded that the fracture zone is a weak zone within the Pacific plate that allowed magmas from a weak hotspot to reach the surface. This project will survey sections of the Marquesas fracture zone using multibeam bathymetric tools, gravity, magnetics, single-channel reflection, and dredging. The survey will study the magmatic expression of three hotspots before, during, and after they encounter the fracture zone. The morphology of the fracture zone at the hotspot intersections will be contrasted with other segments that have not encountered hotspots. The overall goals are to better constrain the origin of fracture zone topography, the intrinsic dimension and temporal continuity of hotspots, their interaction with lithospheric discontinuities, and the azimuth and extent of the oldest section of the Marquesas fracture zone.

在1987年对马克萨斯岛链的考察中，主要研究人员绘制了位于马克萨斯膨胀和马克萨斯断裂带交汇处的高脊的一部分。他们得出的结论是，断裂带是太平洋板块内的一个薄弱地带，它允许来自薄弱热点的岩浆到达地表。该项目将使用多波束测深工具、重力、磁力、单通道反射和疏浚技术对Marquesas断裂带的部分区域进行调查。该调查将研究三个热点在遇到断裂带之前、期间和之后的岩浆表现。将热点交叉处断裂带的形貌与其他未遇到热点的断裂带进行对比。总体目标是更好地约束断裂带地形的起源、热点的内在维度和时间连续性、热点与岩石圈不连续性的相互作用以及Marquesas断裂带最古老部分的方位角和范围。