Collaborative Research: Chemical Geodynamics of the Galapagos Mantle Plume-Spreading Center System

这是一项与来自GEOMAR的德国科学家合作的研究，是2001年在R/V Sonne号上进行的MEGAPRINT探险的一部分。实地考察计划对东加拉帕戈斯扩散中心(GSC)的关键、未绘制的地段以及群岛和扩张中心之间的年轻海底部分进行了采样。该计划的内容包括多波束海底测绘、船上重力和磁力调查，以及通过沿GSC东部和许多离轴海山和火山山脊以约15公里间隔疏浚对熔岩进行采样。在已经完成的大约100个主要元素玻璃分析的指导下，PI提出了一个分析方案，将确定这些具有代表性的海底玻璃和岩石的微量元素含量、氦、铅、钕、锶和氢同位素组成、挥发分(二氧化碳、水、氯、氟和S)含量和40Ar-39Ar辐射年龄。来自德国同事的地球物理数据将提供关于地壳和岩石圈的年龄、结构、厚度和构造的额外限制。

This is a collaborative study with German scientists from GEOMAR, as part of the MEGAPRINT expedition that took place aboard the R/V Sonne during 2001. The field program sampled critical, unmapped sections of the eastern Galapagos Spreading Center (GSC) and portions of young seafloor between the archipelago and the spreading center. Elements of the program included multi-beam seafloor mapping, shipboard gravity and magnetic surveys, and sampling of lavas by dredging at ~15 km spacing along the eastern GSC, and at numerous off-axis seamounts and volcanic ridges. Guided by ~100 major element glass analyses already completed, the PIs propose an analytical program that will determine trace element contents, He, Pb, Nd, Sr and Hf isotope compositions, volatile (CO2 ,H2O, Cl, F and S) contents and 40Ar-39Ar radiometric ages of a representative suite of these submarine glasses and rocks. Geophysical data from German colleagues will provide additional constraints on age, structure, thickness and tectonics of the crust and lithosphere.