Stretching of the Central Pacific Lithosphere: En-echelon Ridges and Crossgrain Lineations on the Superwell

几种类型的地球物理观测表明，中南部太平洋的岩石圈正在经历弥漫性的南北伸展。作为对这一假设的部分检验，首席研究员将调查从东太平洋隆起到土阿莫土群岛北部边缘延伸2500公里的一系列前所未见的雁梯队山脊。拉伸假说的一个主要含义是，西太平洋的一些火山活动可能与岩石圈的拉伸破坏有关，而不是与众多的地幔柱有关。调查的目的是首先确定山脊在未被绘制的地方存在，并且它们是连续的。还将对这些脊进行疏浚，进行岩石学和年龄研究，并确定脊的磁特征。

Several types of geophysical observations indicate that the lithosphere in the southcentral Pacific is undergoing diffuse north-south extension. As a partial test of this hypothesis, the Principle Investigator will survey a previously uncharted series of en-echelon ridges that extend for 2500 km from the East Pacific Rise to the northern edge of the Tuamotu archipelago. A major implication of the stretching hypothesis is that some volcanic activity in the west Pacific may be related to tensional failure of the lithosphere rather than numerous mantle plumes. The goals of the survey are to first establish that the ridges exist where they have not been charted, and that they are continuous. The ridges will also be dredged for petrologic and age studies, and the magnetic signature of the ridges will be determined.