The Dynamics of Mid-Ocean Ridges

大洋中脊的动力学

• 批准号: 8911326
• 负责人: E M Parmentier
• 金额: $ 27.29万
• 依托单位: Brown University
• 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: 1989-08-01 至 1993-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8911326&HistoricalAwards=false
• 关键词: Dynamics; Mid; Ocean; Ridges

This project involves theoretical models aimed at under- standing mid-ocean ridge spreading centers and seafloor struc- ture. The principal investigators have developed 2-D time- dependent convection models that show that thermal and composi- tional density stratification of the mantle beneath spreading centers can lead to fluctuations in crustal thickness. They will now consider the effect of lower mantle viscosities and will specifically test whether high frequency variations in crustal thickness result that might explain the origin of abyssil hill lineations. They will construct 3-D models of magma flow beneath ridges, including flow in a ridge axis conduit to investigate the origin of the inside-corner bathymetric high at ridge-transform interestions and the asymmetry of the median valley near intersections. They will also explore a model for ridge segmentation and episodic spreading based on stresses and deformation in the lithosphere rather than convection in the mantle.

该项目涉及旨在了解洋中脊扩张中心和海底结构的理论模型。 主要研究人员开发了二维与时间相关的对流模型，该模型表明扩张中心下方地幔的热和成分密度分层可能导致地壳厚度的波动。 他们现在将考虑较低地幔粘度的影响，并将专门测试地壳厚度的高频变化是否可以解释深渊山线的起源。 他们将构建山脊下岩浆流的 3D 模型，包括山脊轴管道中的岩浆流，以研究山脊变换兴趣处内角测深高的起源以及交叉点附近中谷的不对称性。 他们还将探索基于岩石圈中的应力和变形而不是地幔中的对流的山脊分割和幕式扩散模型。