EAR-PF Mapping Sharp Interfaces in Continental Rifts

EAR-PF 绘制大陆裂谷中的尖锐界面

• 批准号: 0948303
• 负责人: Vedran Lekic
• 金额: $ 17万
• 依托单位: Lekic Vedran
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0948303&HistoricalAwards=false
• 关键词: EAR; PF; Mapping; Sharp; Interfaces

Dr. Ved Lekic has been granted the NSF Earth Sciences postdoctoral fellowship to carry out a research and education plan at Brown University. He will investigate the causes and mechanics of continental rifting, which is the process in which continents are torn apart and new plate boundaries form. The project will focus on three active continental rifts that span a variety of rates, geometries and amounts of extension, different maturity and geochemical signatures: the Rio Grande Rift, the Salton Trough, and the Ethiopian and Kenyan segments of the East African Rift. Analysis of seismic data (receiver function, tomographic, and forward waveform-modeling analyses) will be used to simultaneously map broad asthenospheric and lithospheric features as well as detect and characterize sharp interfaces such as the crust-mantle boundary, the lithosphere-asthenosphere boundary, and other features that may be related to melting or faulting. Mapping and characterizing horizontal and steeply dipping interfaces associated with active continental rifts of different age, maturity, geochemical signature and deformation parameters will shed light on the causes, mechanics and evolution of rifting. In the last four decades, the plate tectonic paradigm has tremendously enhanced our understanding of how our planet works. Yet, we are still far from understanding how tectonic plates formed in the first place and how continents can break up among multiple plates at locations known as continental rifts. This investigation will create images of structures within continental rifts that can be used to learn about the processes by which continental plates weaken and break apart and the role that Earth's deep interior plays. As such, it may elucidate the way plate tectonics arose and how it continued to operate. The educational component will be centered on two courses: an advanced seminar co-taught by Lekic and the host mentor, and an introductory course in geophysics co-taught by Lekic and a faculty member at the host institution. The advanced seminar, focused on the structure, rheology and dynamics of the continental lithosphere, will directly incorporate the questions raised and insights provided by the research. It will also provide an interdisciplinary venue in which professors, post-doctoral researchers, graduate students, and advanced undergraduates from a variety of geoscience backgrounds can learn and discuss major questions and latest findings. The undergraduate course will allow Lekic to develop, apply and evaluate a suite of active learning techniques and enable him to experiment with activities and approaches that engaging the students' diverse learning styles.

Ved Lekic博士已获得NSF地球科学博士后奖学金，在布朗大学开展研究和教育计划。他将研究大陆裂谷的原因和机制，这是大陆被撕裂和新的板块边界形成的过程。该项目将侧重于三个活跃的大陆裂谷，它们跨越各种速率、几何形状和延伸量、不同的成熟度和地球化学特征：格兰德河裂谷、索尔顿海槽以及东非裂谷的埃塞俄比亚和肯尼亚部分。地震数据分析（接收器功能、层析成像和正演波形建模分析）将用于同时绘制广泛的软流圈和岩石圈特征图，并探测和确定尖锐界面的特征，如壳幔边界、岩石圈-软流圈边界以及可能与熔融或断层有关的其他特征。绘制和描述与不同年龄、成熟度、地球化学特征和变形参数的活动大陆裂谷有关的水平和陡倾界面，将有助于了解裂谷作用的原因、机制和演变。在过去的四十年里，板块构造范式极大地增强了我们对地球如何运作的理解。然而，我们仍然远远没有理解构造板块最初是如何形成的，以及大陆是如何在被称为大陆裂谷的地方分裂成多个板块的。 这项调查将创建大陆裂谷内结构的图像，可用于了解大陆板块弱化和分裂的过程以及地球深部内部所起的作用。因此，它可以阐明板块构造的产生方式以及它如何继续运作。教育部分将集中在两个课程：由Lekic和主办导师共同教授的高级研讨会，以及由Lekic和主办机构的一名教员共同教授的物理学入门课程。高级研讨会的重点是大陆岩石圈的结构，流变学和动力学，将直接纳入研究提出的问题和提供的见解。它还将提供一个跨学科的场所，教授，博士后研究人员，研究生和来自各种地球科学背景的高级本科生可以学习和讨论重大问题和最新发现。本科课程将允许Lekic开发，应用和评估一套主动学习技术，并使他能够尝试参与学生多样化学习风格的活动和方法。