International Postdoctoral Fellows: Paleomagnetic Exploration of the Process of Eduction and Cooling of Deep- Seated Metamorphic Rocks Following Laurentian-Baltic Plate

9403645 McEnroe该奖项是国际青年研究员和博士后研究员计划的一部分，它使美国科学家和工程师能够在国外公认的卓越研究中心进行三到十二个月的研究。该计划的奖励为联合研究提供了机会，并利用独特或互补的设施、专业知识和国外的实验条件。该奖项将支持马萨诸塞大学阿默斯特分校的Suzanne a . McEnroe博士进行为期12个月的博士后研究访问，与挪威地质调查局（NGU）的Trond H. Torsvik博士合作，对挪威西部片麻岩地区劳伦-波罗的海板块碰撞后深层变质岩的教育和冷却过程进行古地磁勘探。变质岩古地磁研究的目的是确定原岩形成时、低温变质作用下新的磁性矿物生长时、高温变质作用后磁性矿物冷却到居里温度（580摄氏度）以下或尼尔温度（670摄氏度）以下时地球磁场的方向。挪威斯堪的纳维亚喀里多尼德山脉的西部片岩区包含了波罗的海板块内各种各样的岩石类型，这些岩石被俯冲到100公里的深处，加热到750摄氏度的温度，然后迅速“排出”，并在劳伦板块较冷的残余物的覆盖下冷却。由于变质岩的粗粒度和组构各向异性等因素，很难从变质岩中获取古磁矢量，但仍有许多具有磁性矿物残余原生分布的明显各向同性榴辉岩和基底辉长岩等目标。利用NGU的先进设备，我们打算利用这个古磁学工具来加深我们对这些深层变质岩中变质反应、冷却变形、时间和磁性特征获取之间关系的理解。这一研究结果将有助于全面了解这些变质岩的深层作用过程、岩石磁性以及大陆碰撞带的地壳历史。＊＊＊

9403645 McEnroe This award is under the International Junior Investigator and Postdoctoral Fellows Program, which enables U.S. scientists and engineers to conduct three to twelve months of research abroad at research centers of proven excellence. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twelve-month postdoctoral research visit by Dr. Suzanne A. McEnroe of the University of Massachusetts at Amherst to work with Dr. Trond H. Torsvik at the Norwegian Geological Survey (NGU) on paleomagnetic exploration of the processes of education and cooling of deep-seated metamorphic rocks following Laurentian-Baltic plate collision in the Western Gneiss Region, Norway. Research on the paleomagnetism of metamorphic rocks is designed to determine the orientation of the earth's magnetic field at the time of formation of the protolith, at the time when new magnetic minerals grew during low-temperature metamorphism, or at the time when magnetic minerals cooled below the Curie temperature (580 degrees Celsius) or Neel temperature (670 degrees Celsius) following high-temperature metamorphism. The western gneiss region of the Scandinavian Caledonides in Norway contains a wide variety of rock types within the Baltic plate that were subducted to depths up to 100 km and heated to temperatures up to 750 degrees Celsius before being rapidly "educted" and cooled against overlying cooler remnants of the Laurentian plate. The acquisition of paleomagnetic vectors from the metamorphic rocks is made difficult by the factors of coarse grain size and fabric anisotropy, but numerous targets of opportunity are available in the form of apparently isotropic eclogites and basement gabbro masses with relict primary distributions of magnetic minerals. Using the superb equipment at the NGU, it is intended to use this paleomagnetic tool to enhance our unde rstanding of the relationships between metamorphic reactions, cooling deformation, time, and the acquisition of magnetic signatures in these deep- seated metamorphic rocks. The results of this research would contribute to overall understanding of deep-seated processes, rock-magnetic properties of these metamorphic rocks, and crustal history in a zone of continental collision. ***