• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Contributions to Mineralogy and Petrology >A trachyte-syenite core within a basaltic nest: filtering of primitive injections by a multi-stage magma plumbing system (Oki-Dozen, south-west Japan)
【24h】

A trachyte-syenite core within a basaltic nest: filtering of primitive injections by a multi-stage magma plumbing system (Oki-Dozen, south-west Japan)

机译：玄武岩巢穴中的曲折长岩芯：通过多级岩浆管道系统（Oki-Dozen，日本西南部）过滤原始注入物

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Oki-Dozen (Japan) is a Late Miocene (7-5 Ma) intraplate alkalic volcano composed of a central trachytic pyroclastic complex surrounded by a ring-shaped succession of basaltic to trachybasaltic lavas and pyroclastic rocks and dispersed trachytic bodies. The central trachytic complex is in contact with a syenite that was intruded into the basement early Miocene volcano-sedimentary succession. In the centre of the system there are no alkalic basaltic rocks that are correlative of the outer flank ring. We present whole-rock major and trace element chemistry, Sr-Nd-Pb isotopic compositions and petrological data from the central trachytic volcanic complex and the intrusive syenite body, as well as from the outer ring basaltic succession. We also present and discuss a new set of zircon U/Pb ages collected from the central trachyte and syenite bodies. All the eruptive products of Oki-Dozen, as well as the syenite, plot on a single liquid line of descent initiated from a mantle-derived alkalic basaltic parent. A younger (2.8 Ma) basaltic eruption (Uzuka basalt) has isotopic compositions that distinguish it from the rest of the system. Geochemical modelling indicates that magmatic differentiation through crystal fractionation and minor crustal assimilation occurred in crustal and shallow sub-volcanic magma reservoirs. In the central part of the system, a number of vertically spaced reservoirs acted as a filter, capturing basaltic dykes and hindering their ascent. In the outer region, dykes either reached the surface unhindered and erupted to form the basaltic/trachybasaltic succession or stalled at crustal levels and differentiated to trachyte before forming dispersed domes/flows. The central plumbing system "filter" resulted in a nest-shaped volcano, with a trachytic core surrounded by basaltic products, and stopped direct injection of basaltic magmas into the shallow syenitic magma reservoir, likely preventing its destabilization and explosive eruption.
机译：Oki-Dozen（日本）是中新世晚期（7-5 Ma）的板内碱性火山，由中央的曲折型火山碎屑复合体组成，周围环绕着环形的玄武岩至曲折的玄武质熔岩和火山碎屑岩以及散布的曲折体。中央的层状复合体与侵入到中新世早期火山沉积相继的基底中的正长岩接触。在系统的中心，没有与外侧翼环相关的碱性玄武岩。我们介绍了全岩石的主要和微量元素化学，Sr-Nd-Pb同位素组成以及来自中央特拉西奇火山岩群和侵入性正长岩体以及外环玄武岩演替的岩石学数据。我们还介绍并讨论了从中央长晶石和正长岩体中收集的一组新的锆石U / Pb年龄。 Oki-Dozen的所有喷发产物，以及正长岩，都在源自地幔衍生的碱性玄武岩母体的单一下降液体线上绘制。年龄较小的（2.8 Ma）玄武岩喷发（Uzuka玄武岩）具有同位素成分，可将其与系统的其余部分区分开。地球化学模型表明，在地壳和浅层次火山岩浆储层中发生了通过晶体分馏和次要地壳同化作用的岩浆分化。在系统的中央，许多垂直隔开的水库充当过滤器，捕获玄武岩堤并阻碍其上升。在外部区域，堤坝不受阻碍地到达地表并喷出，形成玄武岩/速成玄武岩演替，或者停滞在地壳水平，并在形成分散的穹顶/水流之前分化成速殖子。中央管道系统“过滤器”形成了一个巢状火山，其回旋形核心被玄武岩产品包围，并停止了将玄武岩浆直接注入浅层的浆状岩浆储层中，可能阻止了其不稳定和爆炸性喷发。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号