Petrology and Tectonics of the Australian-Antarctic Discordance and Adjacent Ridges

澳大利亚-南极不一致是大洋中脊系统独特而神秘的水深和地质特征，其起源尚不清楚。本奖项将支持一个研究不协调带的综合地球物理和地球化学项目。综合地球化学调查与SeaMARC II侧扫声纳调查以及详细的磁力和重力分析相结合，将提供一个独特的数据集，该数据集将侧重于两个具有根本意义的问题，在全球范围和不整合本身的性质方面：(1)不整合东部边界的地球物理和地球化学性质，这是全球大洋中脊系统中最显著的地球化学和测深不连续之一；(2)轴向深度、轴向形态、脊分段和沿轴向岩石学变化之间的相互关系，所有这些在不和谐的内部和外部都是异常多变的。这项研究是麻省理工学院拉蒙特-多尔蒂地质天文台和夏威夷大学的科学家合作的项目。现场工作将在皇家莫阿纳波号上进行。

The Australian-Antarctic Discordance is a unique and enigmatic bathymetric and geologic feature of the mid-oceanic ridge system whose origin is poorly understood. The present award will support an integrated geophysical and geochemical project to study the Discordance zone. The combination of a comprehensive geochemical investigation with a SeaMARC II side-scan sonar survey and detailed magnetic and gravity analyses will provide a unique data set which will focus on two problems which are of fundamental significance, both on a global scale and with respect to the nature of the Discordance itself: (1) the geophysical and geochemical nature of the eastern boundary of the Discordance which is one of the most pronounced geochemical and bathymetric discontinuities in the global mid-ocean ridge system and (2) the interrelationships among axial depth, axial morphology, ridge segmentation, and along axis petrologic variations, all of which are unusually variable within and outside the Discordance. The study is a cooperative project between scientists at Lamont-Doherty Geological Observatory, Massachusetts Institute of Technology, and the University of Hawaii. Field work will be done from the R.V. Moana Wave.