• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>South African Journal of Geology: Being the Transaction of the Geological Society of South African: Syndie die Verhandelinge van die Geologiese Vereniging van Suid-Afrika >Lithostratigraphy of the Mesoproterozoic Stolzenfels Enderbite (Komsberg Suite), South Africa and Namibia
【24h】

Lithostratigraphy of the Mesoproterozoic Stolzenfels Enderbite (Komsberg Suite), South Africa and Namibia

机译：Mesoprotozoio Stolzenfels exterbite（Komsberg Suite），南非和纳米比亚的Lithostratigraphy

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

The weakly porphyritic, mesocratic to melanocratic brown and grey Stolzenfels Enderbite, charno-enderbite and granodiorite crops out as a northwest-trending, 13 km long elongate pluton that crosses the Orange River border between Namibia and South Africa. It is a member of the late- to post-tectonic Komsberg Suite (~1125 to 1105 Ma) that intruded the pre-tectonic gneisses (~1230 to 1150 Ma) in the Kakamas Domain of the Mesoproterozoic Namaqua- Natal Province. The Stolzenfels pluton shows significant, but generally gradational, variations in texture, mineralogy and degree of deformation. It is most commonly weakly K-feldspar porphyritic or coarse-grained equigranular but can, rarely, be strongly porphyritic. Quartz, plagioclase, antiperthite, hornblende and biotite are the predominant minerals whereas orthopyroxene is present in minor amounts in the charnockitic varieties. Most of the pluton is only weakly deformed but a penetrative Namaqua foliation is observed along the eastern margin. Variably oriented younger discrete shear zones and quartz-filled faults cross-cut the pluton. U-Pb zircon dating of the Stolzenfels Enderbite yielded a concordia age of 1115 ± 5 Ma. Despite the textural and mineralogical variations, the Stolzenfels pluton has a very consistent major and trace element geochemistry. It is has an intermediate composition (mean SiO_2: 60.5 ± 1.4 wt. %) and is strongly metaluminous (mean ASI: 0.78) which, together with the biotite-hornblende ± orthopyroxene mineralogy and the abundance of mafic xenoliths, suggests the source magma was produced by partial melting of older igneous rocks that have not undergone any significant amount of chemical weathering. The eNd and T_(DM) values of -0.69 and 1602 Ma are typical of the Komsberg Suite and point to a significant contribution of older crustal material to the source magma.
机译：弱卟啉，纤维生素棕色和灰色斯托尔氏菌胚胎，Charno-ederbite和Granodiorite造成西北趋势，13公里长的细长芦苇，穿过纳米比亚和南非之间的橙河边界。它是迟到的后构造komsberg套件（〜1125至1105 mA）的成员，侵入了Mesoprotozoice Namaqua-省的Kakamas领域的构造前的神衣（〜1230至1150 mA）。 Stolzenfels钚显示出显着，但通常是渐进的，纹理，矿物学和变形程度的变化。它是最常见的弱k-feldspar卟啉或粗粒粒度，但很少能够强烈地卟啉。石英，Plagioclase，抗哌啶，角强和生物烟石是主要的矿物质，而矫形矿物质在甲状腺素中以少量存在于喹喔啉。大多数芦苇只是弱变形，但沿东部边缘观察到穿透性的南曲叶。方向定向较年轻的离散剪切区域和石英填充的故障交叉切割芦苇。 U-PB锆石的STOLZENFELS Enderbite的约会产生了1115±5 mA的Concordia Age。尽管有纹理和矿物学的变化，但斯托尔岑富尔顿具有非常一致的主要和微量元素地球化学。它具有中间体组合物（平均SiO_2：60.5±1.4重量％），并且是强烈的金属滤光剂（平均值：0.78），其与Biotite-Hornblende±orthopoopoopoopoopope矿物学和乳头Xenoliths的丰度相同，表明源岩浆是通过较旧的火岩偏熔化而产生的，该岩石不经历任何大量的化学风化。 -0.69和1602 mA的末端和T_（DM）值是Komsberg套件的典型，并指向较旧地壳材料对源岩浆的显着贡献。

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