US-Botswana Cooperative Research: Geologic and Geophysical Investigations of the Southwestern Branch of the East African Rift System

0217831Atekwana该奖项支持由Estella Atekwana教授与密苏里-罗拉大学地质与地球物理系、Motsoptse Modisi教授和Henri Kampunzu教授与博茨瓦纳大学地质系以及刚果民主共和国卢本巴希大学地质科学系的Stanislas Sebagenzi教授共同开展的一项为期三年的合作研究项目。他们将研究东非裂谷初期的地质和构造过程。裂谷盆地代表被动边缘发育的初始阶段。它们也是沉积物聚集的目标区域，这些沉积物通常含有古环境和气候指标，可以为过去的气候和全球变化提供重要线索。地震活跃的东非裂谷系统西南分支（EARS）是世界上少数几个可以在大陆伸展开始时研究胚胎裂谷的地方之一——在火山活动发生之前。Atekwana和她的同事将进行运动学研究，结合使用来自博茨瓦纳、赞比亚和刚果民主共和国的现场数据和遥感数据，以便：1)评估现有结构对裂谷盆地发育的作用；2)确定故障的运动学和延伸方向；3)刻画了盆地的几何形态，以及西南支下伏的地壳和岩石圈结构；4)评估断层阵列发展和联动形成边界断层的现有模型；5)建立大陆伸展初期裂谷演化的构造和地质模式。该小组还将绘制潜在地震活动区的地图。该项目结合了Atekwana博士在环境地球物理和构造学方面的专业知识，Kampunzu博士在非洲地质学方面的专业知识，以及构造地质学家Modisi博士的专业知识。塞巴根齐博士一直在研究刚果民主共和国和赞比亚西南部裂谷的延伸，他将提供这些地区的实地数据以及他的重力数据。该项目还包括密苏里-罗拉大学的一名学生和博茨瓦纳大学的一名学生的参与。该项目的研究成果将扩大目前对大陆伸展最早阶段的地质和构造过程的认识。关于潜在地震活动的地图将提供宝贵的灾害和减灾信息，可用于经历世界上一些最大和最具破坏性地震的类似裂缝。这些地图还将提供喀拉哈里沙漠这部分地下地质的详细情况，这可能对矿产资源勘探很重要。国际科学与工程办公室和地球科学司共同为这个项目提供支助。

0217831AtekwanaThis award supports a three-year collaborative research project between Professor Estella Atekwana, with the Department of Geology and Geophysics at the University of Missouri-Rolla, Professors Motsoptse Modisi and Henri Kampunzu, with the Department of Geology at the University of Botswana, and Professor Stanislas Sebagenzi, with the Department of Geological Sciences in the University of Lubumbashi, in the Democratic Republic of Congo. They will study geologic and tectonic processes during incipient rifting in the East African rift.Rift basins represent the initial stages in the development of passive margins. They are also target areas for sediment accumulation, and these sediments typically contain paleoenvironmental and climatic indicators that can provide important clues to past climate and global change. The seismically active Southwestern Branch of the East African Rift system (EARS) is one of the few places in the world where embryonic rifting can be studied at the beginning of continental extension--before volcanism has occurred. Atekwana and her colleagues will conduct kinematic studies, using a combination of field data and remote sensing data from sites in Botswana, Zambia, and Democratic Republic of Congo, in order to: 1) assess the role of pre-existing structures on rift basin development; 2) determine fault kinematics and direction of the extension; 3) characterize the geometry of the basins, and the underlying crustal and lithospheric structure of the Southwestern Branch; 4) assess current models for fault array development and linkage to form border faults; and 5) develop tectonic and geologic models for the evolution of rifts during the incipient stages of continental extension. The group will also map zones of potential earthquake activity. This project combines Dr. Atekwana's expertise in environmental geophysics and tectonics, with Dr. Kampunzu's expert knowledge of African geology, and that of Dr. Modisi, who is a structural geologist. Dr. Sebagenzi has worked on the extension of the Southwestern rift in the Democratic Republic of Congo and Zambia, and he will contribute field data for those locations as well as his gravity data. The project also includes the participation of a student from the University of Missouri-Rolla as well as a student from the University of Botswana. The results of this project should expand the current knowledge about the geologic and tectonic processes that occur during the earliest stages of continental extension. The maps on potential earthquake activity will provide valuable hazard and mitigation information that can be applied to similar rifts that experience some of the largest and most damaging earthquakes in the world. The maps will also provide a detailed picture of the subsurface geology of this part of the Kalahari, which may be important for mineral resource exploration. The Office of International Science and Engineering and the Division of Earth Sciences are jointly providing support for this project.