Collaborative Research: Geomagnetic Field for the Last 5 Ma

9804737Opdyke这项建议是一个多机构合作的项目，旨在改善来自熔岩流的0~5 Ma古地磁记录的质量和时空分布。该项目的最终目标是提高我们对地球发电机如何控制观测到的磁场的理解。具体地说：1)历史和0-3KYR(只分辨北半球)记录中的中高纬度通量叶和北极低气压是否在古地磁时间尺度上持续存在；2)时间平均场和古分子变化是否存在半球差异？为了解决这些问题，私营部门计划在每个地点对水流进行系统的古地磁采样，尽可能广泛地涵盖年龄范围，然后进行详细的高质量实验室分析。只要有可能，就会获取古强度和定向记录。已经选择了14个分布在全球各地的地点进行抽样：该计划旨在补充高质量的现有数据，并避免与其他国际集团正在进行的已知重新抽样重复。选择的具体地点包括两个非常高纬度的地点，一条横穿美洲的南北横断面，以及一处来自澳大利亚东南部的地点。

9804737Opdyke This proposal is for a collaborative multi-institutional project to improve the quality and spatial and temporal distribution of the 0-5~Ma paleomagnetic record from lava flows. The ultimate goal of the project is to improve our understanding of how the geodynamo controls the observed magnetic field. Specifically: 1) Do the mid-high latitude flux lobes and north polar low seen in the historical and 0-3 kyr (only northern hemisphere lobes resolved) records persist over paleomagnetic time scales, and 2) Are there are hemispheric differences in the time-averaged field and paleosecular variation? In order to address these issues, the P.I.s have planned systematic paleomagnetic sampling of flows covering as wide an age range as possible at each location, followed by detailed high quality laboratory analyses. Wherever possible paleointensity as well as directional records will be acquired. Fourteen globally distributed sites have been selected for sampling: the plan is designed to complement existing data of high quality, and avoid duplication of known resampling being carried out by other international groups. The specific places chosen include two very high latitude locations, a north-south transect through the Americas, and a site from south-eastern Australia.