Petrology and Geochronology of Kolekole Volcanics, Waianae Volcano, Hawaii

该项目旨在研究科莱科尔火山的岩石成因，科莱科尔火山是夏威夷瓦胡岛的怀亚奈火山最后一次喷发活动的产物。在某些方面，科莱科尔火山可以被认为是怀亚奈火山的复兴状态。然而，与夏威夷的大多数复兴期火山不同，科莱科尔火山似乎在时间和化学上与怀亚纳火山活动的早期阶段密切相关。PIS将通过研究矿场关系、岩石学和地球化学，以及对科莱科尔和下伏熔岩的放射性测年来研究这种关系。特别是，他们建议测试：1)科莱科尔火山是否可能来自与屏蔽和屏蔽后Waianae火山类似的来源，以及通过何种熔融过程，以及2)影响科尔科尔岩浆的分馏作用的性质和深度，主要是通过使用包裹体斑晶、捕虏晶和包裹体的矿物组合来模拟科尔科尔熔岩的变化。这项研究获得的数据将极大地增加我们对夏威夷火山场关系、夏威夷碱性岩浆化学和演化的认识。它应该会提供科莱科尔火山活动的第一个准确日期。

This project is to investigate the petrogenesis of the Kolekole Volcanics, which represent the products of the last eruptive activity of the Waianae Volcano of Oahu, Hawaii. In some respects the Kolekole can be considered the rejuvenation state of the Waianae Volcano. However, unlike most rejuvenation stage volcanism in Hawaii, the Kolekole appears to be closely related temporally and chemically to earlier phases of Waianae activity. The PIs will investigate this relationship through studies of the field relations, petrology and geochemistry, and radiometric dating of the Kolekole and underlying lavas. In particular they propose to test: 1) whether or not Kolekole Volcanics could have been derived from similar sources as the shield and post-shield Waianae Volcanics, and by what sort of melting processes, and 2) the nature and depth of fractionation affecting Kolekole magmas, principally by modeling Kolekole lava variations using mineral mocpositions of included phenocrysts, xenocrysts and xenoliths. Data obtained in this study will greatly increase our knowledge of Hawaiian volcanic field relations, chemistry and evolution of Hawaiian alkalic magmas. It should provide the first accurate dates of Kolekole volcanism.