RUI: Testing Models of Climate-Induced Geomagnetic Field Behavior with a Record of Pleistocene Paleomagnetic Directions

RUI：用更新世古地磁方向记录测试气候引起的地磁场行为模型

• 批准号: 8803406
• 负责人: Robert Negrini
• 金额: $ 7.66万
• 依托单位: California State University-Bakersfield
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-10-15 至 1991-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8803406&HistoricalAwards=false
• 关键词: RUI; Testing; Models; Climate; Induced

The main focus of this study is to test models of climate- induced geomagnetic field behavior which predict a correlation between time-dependent variations in the volume of global ice and time-dependent variations in the paleomagnetic vector. A previously-published record of Pleistocene variations in 18O from deep-sea sediment cores is used to represent changes in global ice volume for last 500,000 years. The variations in the magnetic field during this time interval are represented by a record of paleomagnetic directional data from a sedimentary sequence exposed in south-central Oregon. Prior to comparing the two records 1) a detailed sampling program was conducted to improve the accuracy of the existing paleomagnetic record and 2) a moving-window cross-spectral analysis was conducted to improve the age control. The latter method is one of three independent age control methods underway at three academic institutions to improve the age control. Angular dispersion analysis and band- pass filtering are among the methods used in the comparison between the improved paleomagnetic record and the 18O record. Whether or not the improvements in age control are sufficient to allow the testing of the above models, the paleomagnetic record will contribute significantly to research in geomagnetism, stratigraphy, and tectonics.

这项研究的主要重点是测试气候引起的地磁场行为的模型，该模型预测了整体冰的体积的时间依赖性变化与古磁载体的时间依赖性变化之间的相关性。 深海沉积物核心的18O更新世变化的记录被用来代表过去500，000年的全球冰量变化。 在此时间间隔内磁场的变化由来自俄勒冈中南部的沉积序列的古磁方向数据记录。 在比较这两个记录之前1）进行了详细的抽样程序，以提高现有的古磁记录的准确性，2）进行了移动窗口跨光谱分析以改善年龄的控制。 后一种方法是在三个学术机构中正在进行的三种独立年龄控制方法之一，以改善年龄控制。 角分散分析和带通滤波是改进的古磁记录与18O记录之间使用的方法之一。 年龄控制的改进是否足以允许上述模型测试，古磁记录将对地磁，地层学和构造学的研究产生重大贡献。