Physical and Structural Properties of the Greenland Ice Sheet Project (GISP II) Deep Core

这个奖项代表了第二次格陵兰冰川的一个要素 图纸项目（GISPII）。 本次调查将集中在 地层、弛豫特征和晶体结构 在峰会现场进行的GISP II深钻的冰芯， 格陵兰. 研究将包括：1）划定每年 2）精确的密度测量，以监测 冰芯随着年龄增长的松弛特性，3） 确定核心松弛的主要机制， 4)晶体尺寸测量作为深度和年龄的函数， 5）c轴组构测量，6）碎片分析 在基底冰芯中。 冰的松弛导致了 必须考虑的机械条件的变化 与岩心样品的制备和分析的关系， 截留气体和化学研究; c轴织物构成了 解释应变历史的主要信息来源 垂直钻取的冰芯所代表的冰柱。 因此，非常仔细地记录这些关键特性， 如果我们要准确评估 深部岩心的深度-年龄关系，并有信心 基于地球化学和圈闭的古气候重建 这些岩心的气体分析。

This award represents one element of the second Greenland Ice Sheet Project (GISPII). This investigation will focus on the stratigraphy, relaxation characteristics and crystalline structure of ice cores from the GISP II deep drilling at the Summit site, Greenland. Studies will include: 1) delineation of annual layering, 2) precision density measurements to monitor the relaxation characteristics of ice cores as they age, 3) determination of the principal mechanisms by which cores relax, 4) crystal size measurements as a function of the depth and age of the ice, 5) c-axis fabrics measurements, and 6) analysis of debris in basal ice cores. Relaxation of ice results in significant changes in their mechanical condition that must be considered in relation to the preparation and analysis of core samples for entrapped gas and chemical studies; c-axis fabrics constitute the primary source of information for interpreting the strain history of the ice column that vertically drilled cores represent. Accordingly, very careful documentation of these key properties of summit site ice cores is essential if we are to accurately assess the depth - age relationship of deep cores and have confidence in paleoclimate reconstructions based on geochemical and entrapped gas analysis of these cores.