The Chemistry and Petrology of Submerged, Young Volcanoes: Bransfield Strait, Antarctica

小行星9317307菲斯克 该奖项支持对南极半岛布兰斯菲尔德海峡地区海底火山和热液喷口岩石的研究。 这是一个大陆边缘裂谷，其中不到100万年的火山形成于上地幔熔融而变薄的大陆地壳上。 在400万年前，该地区正在经历海洋地壳的活跃俯冲。 对布兰斯菲尔德海峡近期地震的地震研究表明，在地表下约55至85公里处存在着一个古老的洋壳板。 当一个又冷又湿的板块沉入地幔时，它会升温，脱水，并将流体排入周围的地幔。 这种流体引起熔融，熔融物向上移动;一些岩浆在表面喷发。 通过检查布兰斯菲尔德海峡的火山岩，调查人员将了解地幔中的岩浆过程以及过去在活跃俯冲期间发生的与海洋地壳再循环进入地幔有关的过程。 这项研究的一个辅助方面涉及火山附近的热液活动。 将对热液蚀变火山岩进行分析，以确定热液蚀变所引起的化学变化。 这项研究利用了已经收集和视觉特征的岩石。 ***

9317307 Fisk This award supports a study of rocks from submarine volcanos and hydrothermal vents in the Bransfield Straits region of the Antarctic Peninsula. This is a continental margin rift in which volcanoes less than 1 million years old have formed on thinned continental crust from melting in the upper mantle. Prior to 4 million years ago, this region was undergoing active subduction of oceanic crust. Seismic studies of recent earthquakes in the Bransfield Strait indicate the presence of an ancient slab of oceanic crust approximately 55 to 85 kilometers beneath the surface. As a cold, wet, slab sinks into the mantle, it heats up, dehydrates, and expels fluid into the surrounding mantle. This fluid induces melting and the melts move upward; some magma is erupted at the surface. By examining the volcanic rocks in the Bransfield Strait, the investigators will learn about magmatic processes in the mantle and about processes related to recycling of oceanic crust into the mantle that occurred in the past, during active subduction. An ancillary aspect of this study relates to hydrothermal activity near the volcanoes. Hydrothermally altered volcanic rocks will be analyzed in order to determine the chemical changes that hydrothermal alteration has caused. This study utilizes rocks that have already been collected and visually characterized. ***