CAREER: Teaching through Research: Plume-Ridge Interactions in the Galapagos as Focus of an Integrated InterdisciplinaryChemistry Curricular Initiative

这项由化学和地球科学系颁发的教师早期职业发展（Career）奖支持劳伦斯大学化学系Karen S. Harpp博士对地幔动力学和羽状脊相互作用的跨学科研究和教育。调查将集中在加拉帕戈斯热点，位于加拉帕戈斯传播中心（GSC）以南，远离南美洲西海岸。这里产生的岩浆受热点和洋中脊控制，因此可以作为地幔流动模式、两源混合程度以及岩石圈结构和动力学细节的示踪剂。区域火山特征，特别是沃尔夫-达尔文线条（WDL）以及平塔岛、马尔切纳岛和基诺维萨岛与山脊和热点的关系尚不清楚。人们提出了三种理解该区域的机制：WDL将羽流物质输送到脊上；边缘处岩石圈软弱；山脊上升流，由于邻近热点，熔体产量增加。每种机制导致对地球化学变化的不同预测。将从沃尔夫、达尔文和基诺维萨收集熔岩样本，并确定它们的化学成分。这些数据将适合于模型，以确定哪种机制最能描述该地区的地质活动。该项目将由本科生进行。此外，基于探究的方法和团队方法将被引入劳伦斯大学的化学实验室，包括一门新的环境实验室课程，本科生将参与当地学校和社区团体的外展活动。加拉帕戈斯群岛火山岛的起源尚不清楚，因为海洋脊和当地热点或火山柱之间存在复杂的相互作用。地质机制将通过研究各个岛屿熔岩流的化学成分来确定。该研究与本科生的教育相结合，这些学生将在加拉帕戈斯群岛的实地工作经验之前在以发现为基础的实验室中做好准备。

This Faculty Early Career Development (CAREER) award by the Divisions of Chemistry and Earth Sciences supports interdisciplinary research and education on mantle dynamics and plume-ridge interactions by Dr. Karen S. Harpp, Department of Chemistry, Lawrence University. The investigation will focus on the Galapagos hotspot, located south of the Galapagos Spreading Center (GSC), off the west coast of South America. The magmas produced here are controlled by both hotspots and mid-ocean ridges, thus serving as tracers of mantle flow patterns, extent of mixing between the two sources, and detailed lithospheric structure and dynamics. The relationship of regional volcanic features, specifically the Wolf-Darwin Lineament (WDL) as well as Pinta, Marchena, and Genovesa islands, to the ridge and hotspot are not well understood. Three mechanisms for understanding the region have been proposed: WDL pipes plume material to the ridge; lithospheric weakness at the lineament; ridge upwelling, with increased melt production because of the adjacent hotspot. Each mechanism results in different predictions for geochemical variation. Sample lavas will be collected from Wolf, Darwin, and Genovesa and their chemical compositions determined. The data will be fit to models to determine which mechanism best describes geologic activity in the area. The project will be carried out by undergraduates. In addition, inquiry-based methods and team approaches will be introduced into chemistry laboratories, including a new environmental laboratory course, at Lawrence University and undergraduate students will be involved in outreach with local school and community groups. The origin of volcanic islands in the Galapagos archipelago is not well understood because of the complex interaction between ocean ridges and local hotspots or plumes. The geological mechanism will be determined by studying the chemical composition of the lava flows at various islands. The research is integrated with education of undergraduate students who will be prepared in discovery-based laboratories prior to experience in field work in the Galapagos.