DEEP down under: The potential for UK-Australian Palaeomagnetism to contribute to a new paradigm in deep Earth studies

深入地下：英国-澳大利亚古地磁学为深层地球研究新范式做出贡献的潜力

• 批准号: NE/S008330/1
• 负责人: Andrew Biggin
• 金额: $ 10.16万
• 依托单位: University of Liverpool
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FS008330%2F1
• 关键词: DEEP; down; under; potential; UK

This project will bring together two of the world's largest, most successful, and mutually distinctive palaeomagnetic groups to characterise the behaviour of Earth's ancient magnetic field and its link with deep Earth dynamics and evolution. Merging the complementary areas of expertise, sampling targets, and laboratory equipment available at Liverpool and Curtin promises to generate a novel longstanding collaboration with the potential to help revolutionise our understanding of Earth's deep interior. The PI has a long term research plan to produce and use the first empirically-based quantitative models of palaeomagnetic field behaviour (palaeo-geomagnetism) back across billions of years of Earth history. The motivation for this is that these will provide a numerical framework for understanding the physics of the geodynamo process and how it has changed with Earth's evolution (including secular cooling of the core and mantle, inner core nucleation and growth, and changes in core-mantle heat flux resulting from mantle convection). These models will also allow assessments to made of the realism of numerical dynamo simulations (including those running under different boundary conditions representing different stages in Earth's evolution). Finally they will provide a tool for improving the constraints provided by measurements of the palaeomagnetic field on past continental reconstructions and tectonic processes (classical palaeomagnetism) - these currently rely on simplistic assumptions concerning the time-averaged field and its variability in time and space.The PI has already secured substantial funding to build these models back to 750 million years ago and this project is designed to initiate a collaboration that will extend this endeavour firstly back to 1215 million years ago and then farther back into the Precambrian. In order to achieve this, we need to: (i) Obtain access to well-dated rocks from before 750 Ma that are reliable palaeomagnetic recorders to enable high quality full vector palaeo-geomagnetic records to be produced (ii) Initiate an intensive global measurement campaign to generate reliable data from such rocks that will constrain the statistical models of palaeo-geomagnetic field behaviour. (iii) Undertake collaborations with world-leading specialists in palaeogeography, classical palaeomagnetism and geodynamics to properly characterise Precambrian palaeo-geomagnetic field behaviour and exploit this information to improve our understanding of continental configurations at its surface and its relationship with deep Earth processes.Our approach will be to utilise the wealth of resources (human, technical and geological) accessible to Curtin and to share the tools and knowledge of palaeo-geomagnetic technqiues developed at Liverpool such that a new antipodal centre of excellence in palaeo-geomagnetic field characterisation is initiated. During this project, we will: (i) undertake collaborative field sampling of Australian Precambrian rocks that are known to behave reliably and share extant samples; (ii) perform reciprocal visits to teach one another about our respective disciplines, obtain measurements at both institutions, share goals and results, and discuss future sampling targets and projects; (iii) use Proterozoic continental reconstructions to improve our global statistical field models and iterate to predict how reconstructions might change as a consequence of how the palaeomagnetic field varied. The outcomes of this project will answer exciting research questions and kick-start a major new collaboration in a timely manner to capitalise on existing NERC and other UK funding and leverage additional funds aimed at producing a new world leading direction in palaeo-geomagnetic research.

该项目将汇集世界上两个最大、最成功且各具特色的古地磁群，以表征地球古代磁场的行为及其与地球深层动力学和演化的联系。合并利物浦和科廷大学的互补专业领域、采样目标和实验室设备，有望产生一种新颖的长期合作，有可能帮助彻底改变我们对地球深层内部的理解。 PI 制定了一项长期研究计划，旨在制作和使用第一个基于经验的定量模型，该模型涉及数十亿年地球历史中的古磁场行为（古地磁）。这样做的动机是，这些将为理解地球发电机过程的物理原理以及它如何随着地球的演化而变化（包括地核和地幔的长期冷却、内核成核和生长以及地核-地幔的变化）提供一个数值框架。地幔对流产生的热通量）。这些模型还将允许对数值发电机模拟的真实性进行评估（包括在代表地球演化不同阶段的不同边界条件下运行的模拟）。最后，他们将提供一种工具，用于改善古磁场测量对过去大陆重建和构造过程（经典古地磁学）所提供的限制——这些目前依赖于关于时间平均场及其在时间和空间上的变化的简单化假设。 PI 已经获得了大量资金来构建这些 7.5 亿年前的模型，该项目旨在启动一项合作，将这一努力首先扩展到 12.15 亿年前，然后更远地回到前寒武纪。为了实现这一目标，我们需要： (i) 获取 750 Ma 之前的定年岩石，这些岩石是可靠的古磁记录仪，能够生成高质量的全矢量古地磁记录 (ii) 启动密集的全球测量从这些岩石中生成可靠数据的运动将限制古地磁场行为的统计模型。 (iii) 与世界领先的古地理学、经典古地磁学和地球动力学专家合作，正确描述前寒武纪古地磁场行为，并利用这些信息来提高我们对大陆表面构造及其与地球深层过程关系的理解。我们的方法将利用科廷可利用的丰富资源（人力、技术和地质），并分享利物浦开发的古地磁技术的工具和知识，以便启动了一个新的古地磁场表征卓越中心。在该项目期间，我们将：（i）对澳大利亚前寒武纪岩石进行合作现场采样，这些岩石已知表现可靠并共享现有样本； (ii) 进行互访，互相传授各自的学科知识，获取两个机构的测量结果，分享目标和结果，并讨论未来的采样目标和项目； (iii) 使用元古代大陆重建来改进我们的全球统计场模型，并迭代预测重建可能因古磁场变化而发生的变化。该项目的成果将回答令人兴奋的研究问题，并及时启动一项重大的新合作，以利用现有的 NERC 和其他英国资金，并利用额外的资金，旨在产生古地磁研究的新的世界领先方向。

项目成果

New Paleointensity Data Suggest Possible Phanerozoic-Type Paleomagnetic Variations in the Precambrian

新的古强度数据表明前寒武纪可能存在显生宙型古地磁变化

• DOI: http://dx.10.1029/2021gc009990
• 发表时间: 2021
• 期刊: Geochemistry, Geophysics, Geosystems
• 作者: Lloyd S

Palaeomagnetic field intensity measurements from the 2.6 Ga Yandinilling dyke swarm (Western Australia)

2.6 Ga Yandinilling 堤坝群（西澳大利亚）的古磁场强度测量

• DOI: http://dx.10.1093/gji/ggad423
• 发表时间: 2024
• 期刊: Geophysical Journal International
• 影响因子: 2.8
• 作者: Hawkins L

Magnetic to the Core - communicating palaeomagnetism with hands-on activities

核心磁力 - 通过实践活动交流古地磁学

• DOI: http://dx.10.5194/gc-5-55-2022
• 发表时间: 2022
• 期刊: Geoscience Communication
• 作者: Van Der Boon A

The PINT database: a definitive compilation of absolute palaeomagnetic intensity determinations since 4 billion years ago

PINT 数据库：自 40 亿年前以来绝对古地磁强度测定的权威汇编

• DOI: http://dx.10.1093/gji/ggab490
• 发表时间: 2022
• 期刊: Geophysical Journal International
• 影响因子: 2.8
• 作者: Bono R

Intensity of the Earth's magnetic field: Evidence for a Mid-Paleozoic dipole low.

地球磁场的强度：中古生代偶极低气压的证据。

• DOI: http://dx.10.1073/pnas.2017342118
• 发表时间: 2021
• 期刊: Proceedings of the National Academy of Sciences of the United States of America
• 影响因子: 11.1
• 作者: Hawkins LMA