RUI Research: Pilot Study of Miocene Volcanic Transition Zone

[9706344 . Bogue] PI提议对1520万年前地磁场极性反转期间爆发的火山序列进行一项实验性古地磁调查。研究区是一段200米厚的玄武岩-安山岩熔岩流，暴露在内华达州的绵羊溪山脉。在初步研究中，PI将确定这个新发现的过渡带记录的完整性，以及是否可以从熔岩中确定古强度。需要解决的科学问题包括：极性反转期间的方向变化是复杂的还是简单的，极性反转后的场强是多少，在视极位置静止的时间间隔内场强是稳定的还是变化的。这些问题的答案将涉及与过渡地磁场的性质有关的激烈争论的问题。＊＊＊

9706344 Bogue The PI proposes a pilot paleomagnetic investigation of a volcanic sequence that was erupted during a polarity reversal of the geomagnetic field 15.2 million years ago. The study area is a 200m thick section of basaltic-andesitic lava flows exposed in the Sheep Creek Range, Nevada. In the pilot study the PI will determine the completeness of the record in this newly-discovered transition zone and whether paleointensities can be determined from the lavas. Scientific questions to be addressed include whether the directional change was complex or simple during the polarity reversal, what was the field strength after the reversal, and whether the field strength was steady or variable during intervals when the apparent pole position was stationary. The answers to these questions will address hotly debated issues related to the nature of the transitional geomagnetic field. ***