Full Vector Studies of the Last 60 Thousand Years Derived From the East Maui Volcano, Hawaii

调查的主要目的是研究在地球核心产生并由夏威夷东毛伊岛火山喷发的熔岩记录的地球古代磁场的变化。我们正在通过采样93个熔岩流来研究古磁场的变化，这些熔岩流的时间跨度从200年到60,000年，最终目的是了解地球磁场是如何在地球内部产生的。该项目包括方向性分析和古强度研究，以实现对过去60,000年来总场矢量的确定。正在使用的古强度实验包括新的多样本并行差分法，以及使用传统的Thellier-Coe方法的实验。这项新技术的优点是，它代表了一种可靠的方法，可以确定与磁性矿物的磁区状态无关的绝对古强度。这项研究的结果将与夏威夷群岛其他地方同时代熔岩获得的古分子变化值进行比较。这项研究的一个重要成果将是进一步完善我们对全球地磁强度变化的知识，目前来自欧洲站点的数据过度描述了这种变化。改进的古强度曲线对于全球磁场模型和开发更真实的地球发电机模型是至关重要的。它们也是使用14C、Be等宇宙成因同位素测年方法的重要制约因素。详细和可靠的古强度曲线在考古学和上第四纪地质学中也是有用的对比和测年工具。该项目涉及与荷兰研究人员的国际合作，并正在支持夏威夷大学马诺阿海洋和地球科学与技术学院的本科生研究项目。该项目有助于扩大任职人数不足群体的参与范围，并有助于支持研究基础设施。

The main purpose of the investigation is to study the variation of the ancient magnetic field of the Earth generated at the core of the planet and recorded by lavas erupted from the East Maui Volcano, Hawaii. We are studying variations of the paleofield by sampling ~93 lava flows that span the time rage of 200 to 60,000 years before present with the ultimate goal of understanding how the magnetic field of the Earth has been generated within the interior of the planet. The project involves directional analyses and paleointensity studies in order to achieve determinations of the total field vector for the last 60,000 years. The paleointensity experiments that are being used include the new Multispecimen Parallel Differential method, as well as those using the conventional Thellier-Coe method. The advantage of the new technique is that it represents a reliable way of determine absolute paleointensities that is independent of the domain state of the magnetic minerals. The results of this study will be compared with the paleosecular variation values obtained from coeval lavas elsewhere in the Hawaiian Islands. An important outcome of this study will be further refinement of our knowledge of global geomagnetic intensity variations, which are currently over represented from data from European sites. Improved paleointensity curves are essential for global magnetic field models and for the development of more realistic geodynamo models. They are also important as fundamental constraints for dating methods that use cosmogenic isotopes as 14C, beryllium etc. Detailed and reliable paleointensity curves are also useful as correlation and dating tools in archeology and upper Quaternary geology.The project involves international collaboration with researchers from the Netherlands, and is supporting undergraduate research projects of students at the School of Ocean and Earth Science and Technology of the University of Hawaii at Manoa. The project is contributing to the broadening of participation of underrepresented groups and in supporting research infrastructure.