Collaborative Research: The time averaged field initiative: addressing a critical data gap

协作研究：平均时间现场倡议：解决关键数据差距

• 批准号: 1345003
• 负责人: Lisa Tauxe
• 金额: $ 25.3万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1345003&HistoricalAwards=false
• 关键词: Collaborative; Research; time; averaged; field

Paleomagnetic data play an important role in a variety of geophysical studies of the Earth, including plate tectonic reconstructions, magnetostratigraphy, and studies of the behavior of the ancient geomagnetic field (which we call paleo-geomagnetism). Ever since its inception, the key assumption in many paleomagnetic studies has been that the average direction of the paleomagnetic field corresponds to one that would have been produced by a geocentric axial dipole (GAD), and that the dip of the magnetic field from the horizontal plane provides data of sufficient accuracy to enable their use in plate reconstructions. This proposal will enhance the underlying data that go into time averaged field models, which assess the degree to which the geomagnetic field can be considered "GAD". What is required are data sets with more than 100 sampling sites from all over the globe. To be of most value the data sets would have both directional and intensity data and have excellent age control. The quality required for meaningful interpretation of the data mean that there are very few places on Earth that have adequate coverage. The task at hand is daunting and must be attacked one study at a time. We propose here to exploit the potential of the volcanic fields of Israel, for which there is an enormous amount of preliminary data in the form of both paleomagnetic directions and K-Ar and 40Ar/39Ar dates. This proposal concerns the understanding of one of the most important physical properties of planet Earth, its magnetic field. Magnetic fields are vectors with both direction and strength. While obtaining ancient field directions is relatively straight-forward, extracting accurate ancient field strength information is not. We propose here to attempt to obtain the full vector information and couple it with accurate age information for a 4-D look at the ancient magnetic field as recorded in the volcanics of Israel. This work can contribute to the understanding of many fundamental processes, including the motions of tectonic plates, the role of the inner core in controlling the geomagnetic field, and establishing the average strength of the magnetic field to place recent observations in perspective. Constraints on the geomagnetic field are important to those who study the dynamical processes in Earth?s deep interior. Also, it will serve as the doctoral dissertation project of a graduate student.

古磁数据在地球的各种地球物理研究中起着重要作用，包括板块构造重建，磁层学以及对古代地磁领域的行为（我们称为古地球网络）的行为。自成立以来，许多古磁研究中的关键假设一直是，古磁场的平均方向对应于一个地理中心轴向偶极子（GAD）所产生的磁场的平均方向，并且磁场从水平平面的倾角倾向提供了足够准确的数据，可以在板块重新构造中使用。该提案将增强进入时间平均场模型的基本数据，该数据评估地磁领域可以视为“ GAD”的程度。需要的是来自世界各地的100多个采样站点的数据集。最有价值的数据集将具有方向性和强度数据，并且具有良好的年龄控制。有意义解释数据所需的质量意味着地球上很少有足够的覆盖范围。手头的任务令人生畏，必须一次攻击一项研究。我们在这里提议利用以色列火山场的潜力，为此，以古磁方向和K-AR和40AR/39AR日期的形式有大量的初步数据。该提议涉及对地球（磁场）最重要的物理特性之一的理解。磁场是具有方向和强度的向量。 在获得古老的田野方向相对直率的同时，提取准确的古老田野强度信息不是。 我们在这里提议尝试获取完整的矢量信息，并将其与准确的年龄信息相结合，以使4-D查看以色列火山中记录的古代磁场。 这项工作可以有助于理解许多基本过程，包括构造板的动作，内核在控制地磁场中的作用，并确定磁场的平均强度，以将最新的观察结果放在透视上。对地磁领域的约束对于研究地球深层内部动力学过程的人很重要。此外，它将作为研究生的博士学位论文项目。

项目成果

Paleointensity Estimates From the Pleistocene of Northern Israel: Implications for Hemispheric Asymmetry in the Time‐Averaged Field

• DOI: 10.1029/2022gc010473
• 发表时间: 2022-08
• 期刊: Geochemistry
• 影响因子: 3.7
• 作者: L. Tauxe;H. Asefaw;N. Behar;A. Koppers;R. Shaar

PSV10: A Global Data Set for 0-10 Ma Time-Averaged Field and Paleosecular Variation Studies

• DOI: 10.1002/2017gc007318
• 发表时间: 2018-05-01
• 期刊: GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
• 影响因子: 3.5
• 作者: Cromwell, G.;Johnson, C. L.;Jarboe, N. A.
• 通讯作者: Jarboe, N. A.