Improved Holocene global geomagnetic field reconstructions based on sediment data

我们建议通过研究全新世古地磁沉积记录的质量来改进跨越过去数千年的全球地磁场重建。全球场模型既用于研究地核中的地球发电机过程，也用于考虑银河系宇宙射线与地球环境相互作用中的地磁场屏蔽效应。目前全新世模型的分辨率和可靠性受到两个原因的限制：一是南半球古地磁数据覆盖范围稀疏，二是数据和测年不确定因素，特别是沉积物数据。重新评估所有根据岩性汇编的沉积物记录，并与全球模型进行比较，将提高对沉积物数据质量的日益加深的理解，可能导致校正方法和改进的年龄模型。我们计划编制一个数据库，其中包含所有可用沉积物记录(如岩性、测年方法)的相关元数据，然后利用这些信息调查个别记录中磁信号的质量和年龄控制。目标是改进全新世磁场重建，作为研究我们星球磁屏蔽的演化及其与行星环境相互作用的先决条件。

We propose to improve global geomagnetic field reconstructions spanning the past millennia by investigating the quality of Holocene paleomagnetic sediment records. Global field models are used both to study geodynamo processes in the Earth’s core and to take into account the shielding effect of the geomagnetic field in the interaction of galactic cosmic rays with our planet’s environment. The resolution and reliability of Holocene field models at present are limited for two reasons: firstly, the sparse southern hemisphere archeomagnetic data coverage, and secondly, large data and dating uncertainties particularly in sediment data. A re-evaluation of all compiled sediment records based on lithology and comparison to global models will improve the growing understanding of sediment data quality, possibly leading to correction methods and improved age models. We plan to compile a database containing relevant meta-data for all available sediment records (e.g. lithology, dating method) and then use this information to investigate the quality of the magnetic signal and age control in individual records. The objective is an improvement of Holocene field reconstructions as a prerequisite to investigate the evolution of our planet’s magnetic shield and its interaction with the planetary environment.