Collaborative RUI: Uranium-Series Constraints on Melting in the Jan Mayen Region

大西洋中脊，特别是冰岛北部北冰洋的部分，产生了新的地壳，具有丰富的微量元素地球化学特征，与正常的大西洋中脊玄武岩不同。这种不寻常的化学性质是一个谜，它的起源是有争议的，一些证据表明熔岩是热点起源，但与冰岛下面最近的已知热点无关，其他证据指向被困次大陆物质的融化，这是由5300万至5500万年前格陵兰盆地的地质新近开放造成的。这个问题的解决会影响我们对地幔的理解，并对其他经历异常火山活动的地区产生影响，如亚速尔群岛和阿森松岛。本研究考察了冰岛附近科尔拜因西山脊上扬马延岛的地球化学异常熔岩，以确定它们的来源、熔体产生和运输的时间和机制。手头的样品和德国高分辨率野外测绘巡航收集到的样品将进行放射性同位素（Sr, Nd， Pb和Hf）和u系列同位素的分析。更好地了解正在调查的地区将提供有关融化如何在深度发生并导致火山活动的重要信息。这项工作的更广泛影响包括支持一所女子文理学院的一名来自科学领域代表性不足的群体的早期职业研究者，以及培训女本科生使用最先进的高端铀系列测年技术。这项工作还包括与瑞典、英国和德国的科学家进行广泛的国际合作，在其他实验室对学生进行交叉培训，并让他们参加一次前往北极的国际海洋学巡航。

The Mid-Atlantic Ridge, particularly its segments in the Arctic Ocean north of Iceland, produce new crust that has a trace element-rich geochemical signature that differs from normal mid-ocean ridge basalts. This unusual chemistry is an enigma and its origins are disputed, with some evidence indicating that the lavas are of hotspot origin, but not related to the closest known hotspot which is under Iceland, and other evidence pointing to the melting of trapped subcontinental material resulting from the geologically recent opening of the Greenland Basin 53-55 million years ago. Resolution of this question impacts our understanding of the mantle with implications for other regions along the mid-ocean ridge system that experience anomalous volcanism such as the Azores and Ascension. This research examines geochemically anomalous lavas from Jan Mayen Island on the Kolbeinsey Ridge near Iceland to determine their source and the timing and mechanisms of melt generation and transport. Both in-hand samples and those to be collected on a German high-resolution field mapping cruise to the area will be analyzed for radiogenic isotopes (Sr, Nd, Pb, and Hf) and U-series isotopes. A better understanding of the region under investigation will provide important information about how melting occurs at depth and leads to volcanic activity. Broader impacts of the work include support of an early-career investigator from a group under-represented in the sciences at a women's liberal arts college and training of female undergraduate students in state-of-the-art high-end Uranium series dating techniques. The work also involves extensive international collaboration with Swedish, UK, and German scientists and cross training of students in other laboratories as well as having them participate in an international oceanographic cruise to the Arctic.