Geochemistry of Gases in the Alpine Fault, DFDP-2

新西兰南岛的阿尔卑斯断裂带是一个主要特征，虽然历史上没有发生过大地震，但其向北移动速度为27mm /年，隆升速度很快。在ICDP项目DFDP-2进入高山断层的背景下，我们建议对从钻井泥浆和井下流体采样器中在线提取的气体组成进行系统和全面的研究，这些数据将在2014年的钻井活动中获得。所提出的技术提供了来自钻探岩石、断层和蚀变带的所有自由循环流体的信息，从而允许对穿过阿尔卑斯断层的钻探剖面的挥发性成分进行定性和半定量评估。在选定的气体样品中，我们将测定主要和微量气体组分（CO2, N2, CH4, Ar， He等）的丰度，稀有气体（He, Ne, Ar, Kr, Xe）和CO2和CH4中12C/13C的元素和同位素组成。根据断裂带上下各个流体系统的化学特征，我们希望能够回答以下关键问题：沿阿尔卑斯断裂带的印澳板块和太平洋板块的气体组成是否存在系统的成分差异？深层构造元素与地表温泉之间是否存在水力联系？

The Alpine Fault on the South Island of New Zealand is a major feature, showing a NE movement of 27 mm/yr and rapid uplift although no major earthquakes have occurred in historic time. In the context of the ICDP project DFDP-2 into the Alpine Fault, we propose to perform a systematic and comprehensive study on the composition of gases extracted on-line from drill mud and from down hole fluid samplers, which will be obtained during the drilling campaign in 2014.The proposed technique provides information on all free circulating fluids from the drilled rock, faults and alteration zones and allows, thus, to make a qualitative and semi-quantitative assessment of the volatile components along the drilled profile through the Alpine fault. In selected gas samples we will determine the abundances of major and trace gas components (CO2, N2, CH4, Ar, He etc.), the elemental and isotopic compositions of the noble gases (He, Ne, Ar, Kr, Xe) and 12C/13C in CO2 and CH4.Based on the chemical characterization of the individual fluid systems above and below the fault zone we hope to provide answers to the key question: Are there any systematic compositional differences in the gas composition of the Indo-Australian and Pacific plates along the Alpine fault, and does a hydraulic connection exist between the structural elements at depth and the hot springs at the surface?