...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Sedimentology: Journal of the International Association of Sedimentologists >Significance of the chemistry and morphology of diagenetic siderite in clastic rocks of the Mesozoic Scotian Basin
【24h】

Significance of the chemistry and morphology of diagenetic siderite in clastic rocks of the Mesozoic Scotian Basin

机译：中生代苏格兰盆地碎片岩石岩石化学与形态的重要性

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

Siderite (FeCO3) is a widespread minor diagenetic mineral in clastic sedimentary basins. Although eodiagenetic authigenesis of siderite is well-known, siderite formed during burial diagenesis shows habits and chemical compositions that are poorly understood. This study tests the hypothesis that diagenetic siderite cements in sandstones in the Scotian Basin, offshore eastern Canada, show systematic variability in chemistry and habit that is a response to recrystallization and changing composition of basinal fluids. Mineral textures were determined from backscattered electron images, and chemistry mostly from electron microprobe analyses. Five chemical types of siderite are identified using k-means cluster analysis, based on the amount of substitution of Ca, Mg and Mn for Fe. Eodiagenetic microcrystalline coated grains, concretions and intraclasts in sandstones are principally Fe-rich siderite and locally have recrystallised to blocky equant crystals. Mesodiagenetic Mg-rich siderite partly replaced these equant crystals and also framework mica and K-feldspar grains, showing textural evidence for coupled dissolution-reprecipitation. Slender Mg-rich siderite rhombs (lozenges, bladed or wheat-seed siderite) have precipitated before and after the formation of quartz overgrowths in geochemical microenvironments. Magnesium substitution reflects Mg-rich formation waters resulting from smectite to illite conversion. Equivalent Ca-rich siderite occurs where sandstones overlie a Jurassic carbonate bank. Late Mn-rich siderite has complex textures resembling those of Mississippi-Valley type ores, with spheroidal rims, a honeycomb-like mesh and concentric infill around secondary pores. It also occurs in veins or replacing intraclasts, post-dating late ferroan-calcite cements in sandstones that show strong dissolution by hot basinal brines. The Ca, Mg and Mn content of diagenetic siderite, coupled with textural evidence for recrystallization, can thus be used to track changes in ambient formation fluids. Siderite habits and chemistry described from the Scotian Basin are found in many clastic basins, suggesting that the observed recrystallization textures and variation in chemical type are of broad application.
机译：普拉特（FECO3）是碎片沉积盆中广泛的次要成岩矿物。尽管悬垂的eDiaGeneticaTeate is是众所周知的，但在埋葬成岩作用期间形成的含水极显示出植物和化学组成似乎很差。本研究试验假设苏格兰山地盆地，加拿大东部砂岩中的成岩石水泥，表现出化学和习惯的系统可变性，这是对重结晶和变化的基流液组成的反应。矿物纹理由反向散射电子图像确定，并且大多来自电子微探针分析。使用K-Means簇分析，基于Ca，Mg和Mn的Fe的取代量来鉴定五种化学类型的含锌。卫星中的eodiaGenetic微晶涂层籽粒，凝结和夹层的含蓄粒子主要是Fe富含Fe的菱铁矿，并且局部重结晶至斜纹均匀的晶体。 MesodiaGenetic Mg-Rich散晶部分部分取代了这些刻晶晶体，也是框架云母和K-Feldspar晶粒，显示出耦合溶解的致溶解的纹理证据。在地球化学微环境中形成石英过度生长之前和之后，沉淀了含有富含含量的富含颗粒状rhombs（锭剂，叶片或小麦 - 种子泥炭沸石）。镁取代反射富硅矿对illite转化产生的富含Mg的形成水域。当量的CA富有的泥石物发生在砂岩覆盖侏罗纪碳酸盐堤。富含Mn-Rich的泥石物具有复杂的纹理，类似于密西西比河谷型矿石，带有球缘轮辋，蜂窝状网状网状物和次要毛孔周围的同心填充物。它还发生在静脉或替代床中，在砂岩后的后期酿酒酯，显示出强烈溶解的热盆盐水。因此，与重结晶的纹理证据相结合的成岩颗粒的Ca，Mg和Mn含量可以用于跟踪环境形成液中的变化。斯科氏盆地中描述的泥石矿习惯和化学在许多碎片盆地中被发现，表明观察到的重结晶纹理和化学类型的变化具有广泛的应用。

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