Collaborative Research: Morphology and Timing of the Reunion/Huckleberry Ridge Event(s)

合作研究：团聚/哈克贝利岭事件的形态和时间安排

• 批准号: 0943584
• 负责人: Bradley Singer
• 金额: $ 8.4万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-15 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0943584&HistoricalAwards=false
• 关键词: Collaborative; Research; Morphology; Timing; Reunion

The strength of the Earth's magnetic field is important to modern society because it protects Earth and its communication satellites from harmful levels of solar radiation. During periods when the Earth's relative magnetic field strength drops (e.g., during solar flares), increased amounts of solar radiation are allowed to penetrate further into the upper atmosphere causing damage to satellites and interfering with shortwave radio communication. For this reason, it is important to understand the natural short-term variability of the Earth's magnetic field. Records of past geomagnetic field behavior are well-preserved by magnetic minerals within volcanic and sedimentary rocks. Although scientists have long used these records to study the long-term history of magnetic polarity reversals, records of more short-lived geomagnetic instabilities are poorly resolved in time, typically incomplete, and lacking in detail. Developing enhanced, global records with precise age control is essential to identifying common trends during and leading to magnetic field instability.The research supported by this grant aims to produce the most globally complete record of unstable geomagnetic field behavior to date. We plan to integrate magnetic records collected from volcanic and sedimentary rocks from around the world in order to compile a chronologically calibrated, continuous full-vector record of geomagnetic field behavior during the Réunion geomagnetic event, which occurred roughly two million years ago. This research will allow us to address several fundamental questions: How quickly to geomagnetic instabilities manifest themselves? Do geomagnetic instabilities occur synchronously around the world, or do they affect some geographic regions longer and more severely than others? How weak is the Earth's magnetic field during an instability event? In addition to helping resolve these questions, the data generated during this research will be key to future efforts aimed at modeling the complete behavior of the Earth?s magnetic field and will refine the magnetostratigraphy of the Lower Quaternary, thereby improving the correlation of strata on a global scale.

地球磁场的强度对现代社会很重要，因为它保护地球及其通信卫星免受有害水平的太阳辐射。在地球相对磁场强度下降期间(例如，在太阳耀斑期间)，增加的太阳辐射量被允许进一步穿透到高层大气，对卫星造成损害，并干扰短波无线电通信。因此，了解地球磁场的自然短期变化是很重要的。火山岩和沉积岩中的磁性矿物很好地保存了过去地磁场行为的记录。尽管科学家们长期以来一直使用这些记录来研究磁极反转的长期历史，但对更短暂的地磁不稳定的记录在时间上解决得很差，通常是不完整的，而且缺乏细节。开发具有精确年龄控制的增强的全球记录，对于识别磁场不稳定期间和导致磁场不稳定的共同趋势至关重要。这项赠款支持的研究旨在产生迄今为止全球最完整的不稳定地球磁场行为记录。我们计划整合从世界各地的火山岩和沉积岩收集的磁性记录，以便汇编一份按年代校准的、连续的全矢量记录，记录大约200万年前发生的留尼汪岛地磁事件期间的地磁场行为。这项研究将使我们能够解决几个基本问题：地磁不稳定性多快表现出来？地磁不稳定是在世界各地同步发生的，还是它们对某些地理区域的影响比其他地区更长、更严重？在不稳定事件期间，地球的磁场有多弱？除了帮助解决这些问题外，这项研究期间产生的数据将是未来旨在对地球-S磁场的完整行为进行建模的关键，并将完善下第四系的磁性地层学，从而改善全球范围内的地层对比。