EAR-PF: Separating Regional from Global Influences on the Paleomagnetic Record

Leah齐格勒博士已获得NSF地球科学博士后奖学金，在俄勒冈州州立大学开展研究和教育计划。 她将研究地球磁场强度的变化，这是几十万年来海洋沉积物中记录的。 这项研究将侧重于使用时间序列分析，统计和逆向建模，以评估区域间和区域内的一致性的数据从几十个不同的沉积物芯。 将利用地球仪上按区域聚集的数据制作磁场强度模型，并将这些不同的区域模型相互比较，并与全球参考模型进行比较。 此外，她还将量化地理位置接近和地理位置远离的各个核心之间的相关性，以测试相关性和地理分离之间是否存在关系。 该项目的首要目标是确定全球和区域领域的功能在很长的时间尺度上，并确定是否区域规模的功能（这是更难以解决）以上的噪音是固有的数据源是可观察的。 地球的磁场是不断变化的：在强度，小规模的形状，和极点的位置。 虽然磁场近似为偶极场，但它有许多复杂性和偏离这一概括。 一些特定的非偶极特征可能持续数百或数千年，而另一些仅持续几年。 今天的磁场的全部细节很容易从卫星和天文台的测量中观察到。 然而，恢复古代磁场的细节直到现在才变得可行，通过仔细分析来自磁化沉积物的越来越多的数据。 这项研究提供了一个框架，了解如何以及我们可以解决领域的复杂性，从这个嘈杂的，但信息丰富的数据源。 在沉积物中看到的场强的特征起伏通常在广泛的环境应用中用作这些沉积物的年代学工具，其中典型的偶极场近似导致年代学不准确。 这项研究将导致更好的时间精度和误差范围在这些应用程序。 在这项工作中产生的对古代磁场的更好的理解也将导致对最终产生磁场的地球深部过程的新见解。 除了她的研究，该研究员将通过各种既定的K-12外展计划积极参与OSU的教育和外展活动。 她还将在俄勒冈州立大学共同教授一门关于“地球磁场”的本科课程。

Dr. Leah Ziegler has been granted an NSF Earth Sciences postdoctoral fellowship to carry out a research and education plan at Oregon State University. She will investigate the changing strength of the Earth's magnetic field, as recorded in marine sediments over hundreds of thousands of years. This study will focus on using time series analysis, statistics, and inverse modeling to assess the interregional and intraregional consistency of data taken from dozens of separate sediment cores. Models of magnetic field strength will be made using data clustered regionally on the globe, and these different regional models will be compared with each other and with a global reference model. Additionally, she will quantify the correlation between individual cores which are geographically close together and which are geographically far apart, to test if there is a relationship between correlation and geographic separation. The overarching goal of this project is to identify global and regional field features on very long timescales, and to determine if the regional-scale features (which are more difficult to resolve) are observable above the noise which is inherent to the data source. The Earth's magnetic field is ever-changing: in strength, small scale shape, and pole location. Although the magnetic field is approximately a dipole field, it has many complexities and deviations from this generalization. Some specific non-dipole features may last hundreds or thousands of years, while others last only a few years. The full detail of today's field is readily observable from satellite and observatory measurements. However, recovering details of the ancient magnetic field is only now becoming feasible through careful analyses of growing amounts of data from magnetized sediments. This study provides a framework for understanding how well we can resolve field complexities from this noisy - yet informative - data source. The characteristic ups and downs in field strength seen in sediments often serve as a chronology tool for those sediments in a wide range of environmental applications, where the typical dipole field approximation contributes to chronological inaccuracies. This study will lead to better chronological accuracy and error bounds in these applications. The improved understanding of the ancient magnetic field produced in this work will also lead to new insights into the deep earth processes that ultimately give rise to the magnetic field. In addition to her research, the fellow will be active in education and outreach at OSU through a variety of established K-12 outreach programs. She will additionally co-teach an undergraduate level course on "Earth's Magnetism" at OSU.