Full vector paleosecular variation (PSV) recorded on the Koolau Volcano, Oahu, Hawaii during the Matuyama Chron at Makapuu Point (ca. 2.6 to ~2.2 Ma).

古地磁（即化石磁学）数据是了解地磁转变的独特观测来源，因此了解磁场产生中涉及的地球动力学过程。由于需要从火山序列中获得反转记录，以便更好地了解地球磁场的产生，因此建议研究夏威夷瓦胡岛（Oahu）库劳火山（Koolau Volcano）马卡普乌点（Makapuu Point）的一长段（约191米）熔岩序列，主要目的是研究几次连续极性转变前后记录的全范围古地磁信号。覆盖约41万年磁场变化的部分包括研究连续磁场逆转的详细记录的可能性，如高斯-松山，隐时子C2r。由于该剖面底部年龄为260 +/- 13万年，中部年龄为2.49+/- 07万年，而在剖面顶部下方约10 m处年龄为~ 219 +/- 12万年。这项为期2年的研究的目标是了解反转和偏移等时期的场变化，以及迄今为止仅从少数沉积层序中记录的反转前后的关键时间间隔，时间间隔在2.6至~2.012 Ma之间。反转研究不能与周围的极性间隔分开，迄今为止发表的大多数记录都不够长，无法提供完整的信息。该序列提供了一个特殊的机会来研究一段时间内的变化，包括几个极性间隔，从而记录了不同时间常数下的古场行为。这是提取古油气田生成的基本条件，并对古油气田生成的理论和数值模拟提出了重要的约束条件。该研究将对静磁学、岩石磁学、地磁学和物理火山学等领域产生影响。几名本科生将得到支持并参与研究的各个方面。为了确定“稳定”极性的总场矢量和古长期变化（PSV），建议着重进行全矢量研究。这项研究将集中在连续的极性周期和它们相关的反转上。古强度实验将使用一种版本的Thellier-Coe以及差分pTRM“多标本”方法进行。pi对受磁矿物学转化影响的样品和涉及多畴颗粒的磁化成分施加了严格的丢弃标准。为了进行适当的统计处理，处理依赖于每流至少5到8次测定的古强度值是很重要的。考虑到古强度研究的耗时方面，预计需要两年的时间来实现本提案的目标，其中包括10个以上的40Ar/39Ar辐射年龄测定。首席研究员和四名本科生将完成整个研究项目。在这个项目中，本科生的参与将是一个优先事项，包括实地考察、实验室工作、分析和发表结果。数据将通过出版物和网络以及社区维持的古地磁和地质年代学数据库传播。该项目将为维持犹他大学和稀有气体实验室的古磁学运行提供刺激。来自世界各地的学生和研究人员都在使用这两个网站。

Paleomagnetic (i.e. fossil magnetism) data are the unique source of observations to understand the geomagnetic transitions and hence the geodynamo processes involved in field generation. Due to the fact that there is a need to obtain reversal records from volcanic sequences in order to have a better understanding of the generation of the Earth's magnetic field, it is proposed to study a long sequence (about ~191 meters) of lavas from the island Oahu, Hawaii at a site known as Makapuu Point, Koolau Volcano with the main objective of investigating the full range of paleomagnetic signals recorded before during and after several successive polarity transitions. The section covering ~410,000 years of field changes includes the possibility of studying the detailed recording of the successive magnetic field reversals such as the Gauss-Matuyama, Cryptochron C2r.2r-1 and the onset of the Reunion Subchron, since the base of the section is 2.60+/-0.13 million years old, the middle part is 2.49+/-0.07 million years old and about 10 m below the top of the section the age is ~2.19+/-0.12 million years old. The objectives of this 2 year research study are related to the knowledge of field variations during periods like reversals and excursions and related to the critical time intervals that precede and follow reversals that so far have only been documented from a few sedimentary sequences, for the interval between 2.6 to ~2.012 Ma. Reversal studies cannot be separated from the surrounding polarity intervals and most records published so far were not long enough to provide complete information. The sequence offers the exceptional opportunity to study changes over a time period that includes several polarity intervals and thus documents the paleofield behavior over various time constants. This is a basic condition to extract and bring up significant constraints for the theoretical and numerical modeling of the generation of the paleofield. This research will have impacts on field like magnetostatigraphy, rock magnetism, geomagnetism and physical volcanism. Several undergraduate students will be supported and involved in all aspects of the research.The proposal is focused on full vector studies in order to determine the total field vector and Paleosecular Variation (PSV) of the "stable" polarities. The study will focus on the successive periods of polarity and their associated reversals. The paleointensity experiments will be conducted using a version of the Thellier-Coe as well as the differential pTRM "multi-specimen" methods. The PIs have imposed severe criteria to discard samples affected by magneto-mineralogical transformations and with magnetization components involving multi-domain grains. It is important to deal with paleointensity values that rely on a minimum number of 5 to 8 determinations per flow in order to perform suitable statistical treatment. Given the time consuming aspect of paleointensity studies, a two-year period is envisaged to achieve the goals of this proposal including 10 more radiometric 40Ar/39Ar age determinations. The principal investigator and four undergraduate students will carry out the entire research project. The involvement of undergraduate students will be a priority in this project, from fieldwork, laboratory work, analysis and publication of the results. Data will be disseminated through publication and on the web and community maintained paleomagnetic and geochronologic databases. This project will provide the stimulus to maintain the paleomagnetics operation at UH and the Rare Gas Lab. at the Univ. of Wisconsin at Madison both of which are used by a diverse group of students and researchers from all over the world.