Collaborative Research: Emplacement of the Ferrar Mafic Igneous Province: A Pilot Study of Intrusive Architecture and Flow Directions in Southern Victoria Land

该奖项由极地方案办公室南极地质和地球物理方案提供，为一项研究提供资金，以调查费勒岩浆省，以了解该省的形成及其在冈瓦那超大陆解体中的作用。冈瓦那的扩散代表着显生宙最大的超大陆分裂事件之一。解体与一个非常大的侏罗纪镁铁质火成岩省的侵位有关，这些火成岩省横跨卡鲁(南部非洲)、费拉尔(南极洲)和塔斯曼(澳大利亚)地区，包括大陆溢流玄武岩和广泛的侵入玄武岩。将3000公里的费拉尔省的发展与地幔热柱、主要岩浆管道或多个来源联系起来的模型，对费拉尔省内的岩浆运输模式进行了可检验的预测。该项目是一项试验性研究，使用了几种不同的技术，旨在评估这些模型，并更好地了解与维多利亚州南部费勒镁铁质侵入省相关的侵位机制、流动方向和岩浆结构。我们的研究工具将包括基于构造野外研究和地球化学对比技术的侵入几何学地图绘制。侵入杂岩内的岩浆流动方向将使用磁化率的各向异性以及介观和岩石组构流动指示器进行评估。这些结果将有助于解决镁铁质大火成岩省岩床和岩脉侵位过程中有关岩浆几何、传播和流动模式的突出问题。它还将加深对地幔热柱、玄武岩岩浆作用和大陆解体之间的关系的理解。

This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a study to investigate the Ferrar magmatic province toward understanding of the formation of this province and its role in the breakup of the Gondwana supercontinent. The dispersal of Gondwana represents one of the largest supercontinent breakup events in the Phanerozoic. Breakup was associated with the emplacement of a very large Jurassic mafic igneous province extending across the Karoo (southern Africa), Ferrar (Antarctica), and Tasman (Australia) regions, comprising continental flood basalts and extensive intrusive dolerites.Models linking development of the 3,000 km Ferrar province to a mantle plume, a major magma conduit, or multiple sources, make testable predictions about magma transport patterns within the Ferrar province. This project is a pilot study using several different techniques aimed at evaluating these models and providing a greater understanding of the emplacement mechanisms, flow directions, and magmatic architecture associated with the Ferrar mafic intrusive province in southern Victoria Land. Our research tools will include mapping intrusive geometry based on structural field studies and geochemical correlation techniques. Magma flow directions within the intrusive complex will be evaluated using anisotropy of magnetic susceptibility, and mesoscopic and petrofabric flow indicators. These results will help resolve outstanding questions concerning the geometry, propagation, and flow patterns of magma during emplacement of sills and dikes in mafic large igneous provinces. It will also provide a deeper understanding of the relationships between mantle plumes, basaltic magmatism and continental breakup.