The upper mantle structure of southern Africa using full-waveform tomography from long-period ambient noise and earthquake data

使用长周期环境噪声和地震数据的全波形断层扫描显示南部非洲的上地幔结构

• 批准号: 1349684
• 负责人: Erica Emry
• 金额: $ 8.7万
• 依托单位: Emry Erica L
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-03-01 至 2016-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1349684&HistoricalAwards=false
• 关键词: upper; mantle; structure; southern; Africa

Dr. Erica Emry has been awarded an NSF Earth Sciences Postdoctoral Fellowship to carry out research and to broaden participation of underrepresented minorities in the Earth Sciences while at The Pennsylvania State University and The University of Rhode Island. She will investigate the structure of the upper mantle beneath Africa using new full-wave seismic tomography techniques on ambient noise and earthquake data. She will address questions of African mantle dynamics and their impact on surface processes by creating a synoptic map of the upper mantle shear velocities throughout southern Africa, focusing on the East African Rift system (EARS) and the Archean cratons. In particular, she will focus on imaging three unresolved regions in the African mantle and answering the following questions that will help to elucidate the relationships between mantle flow, cratonic lithosphere and surface processes: 1) What is the depth and lateral extent of the Congo craton? 2) Are the East African and Ethiopian low velocity zones connected at the Turkana Depression? 3) What is the depth and lateral extent of the Afar hotspot, and are the slowest upper mantle anomalies associated with the Afar hotspot located beneath the Main Ethiopian Rift (MER) or the Afar Depression? Results from this project will contribute to the larger African geology and tectonics community and current research initiatives such as the NSF GeoPRISMs Rift Initiation and Evolution (RIE) program. The finalized results of upper mantle structure beneath southern Africa will be made freely available online for use in other geophysics and earth science research (http://www.iris.edu/dms/products/emc/). As part of this proposal, Dr. Emry will expand upon the Africa Array diversity program, acting as primary instructor for the summer geophysics field course in 2014 and 2015. This course run by Penn State and the University of Witwatersrand brings undergraduate students from minority-serving institutions to Penn State and South Africa to learn geophysical field techniques and South African geology. In addition to the field course, she will continue to mentor students from the Africa Array diversity program on a monthly basis during online webinars, by introducing them to new research, and by discussing careers in the geosciences. Furthermore, during each school year, she will advise students from the Africa Array diversity program who are interested in completing a senior thesis focused on African tectonics or seismology.

Erica Emry 博士获得了美国国家科学基金会地球科学博士后奖学金，以在宾夕法尼亚州立大学和罗德岛大学期间开展研究并扩大代表性不足的少数群体对地球科学的参与。 她将利用环境噪声和地震数据的新型全波地震层析成像技术来研究非洲下方的上地幔结构。她将通过创建整个南部非洲上地幔剪切速度的概要图，重点关注东非裂谷系统（EARS）和太古代克拉通，解决非洲地幔动力学及其对地表过程的影响问题。 特别是，她将重点对非洲地幔中三个未解决的区域进行成像，并回答以下问题，这将有助于阐明地幔流、克拉通岩石圈和地表过程之间的关系：1）刚果克拉通的深度和横向范围是多少？ 2）东非和埃塞俄比亚低速带在图尔卡纳凹陷处相连吗？ 3）阿法尔热点的深度和横向范围是多少？与位于埃塞俄比亚主裂谷（MER）或阿法尔凹陷下方的阿法尔热点相关的最慢的上地幔异常是多少？该项目的结果将为更大的非洲地质和构造界以及当前的研究计划做出贡献，例如 NSF GeoPRISM 裂谷启动和演化 (RIE) 计划。 南部非洲下上地幔结构的最终结果将在网上免费提供，用于其他地球物理学和地球科学研究（http://www.iris.edu/dms/products/emc/）。 作为该提案的一部分，Emry 博士将扩展 Africa Array 多样性计划，担任 2014 年和 2015 年夏季地球物理现场课程的主要讲师。该课程由宾夕法尼亚州立大学和威特沃特斯兰德大学举办，招收来自少数族裔的本科生。为宾夕法尼亚州立大学和南非的机构提供服务，学习地球物理现场技术和南非地质学。 除了实地课程之外，她还将继续每月在在线网络研讨会上指导非洲阵列多样性计划的学生，向他们介绍新的研究，并讨论地球科学领域的职业。 此外，在每个学年，她将为非洲阵列多样性项目有兴趣完成专注于非洲构造或地震学的高级论文的学生提供建议。