Feldspar alteration and Fe minerals: origin, distribution and implications for sandstone reservoir quality in estuarine sediments
Feldspar alteration and Fe minerals: origin, distribution and implications for sandstone reservoir quality in estuarine sediments
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长石蚀变和铁矿物：起源、分布及其对河口沉积物砂岩储层质量的影响
DOI：
10.1144/sp435.17
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
R. Worden
中科院分区：
文献类型：
--
作者：
R. Worden
摘要 现代沉积体系中矿物的产状和分布为揭示古代和深埋砂岩中储层控质矿物的起源和分布提供了许多线索，但定量研究很少。在这里，我们使用了一系列技术，包括 X 射线衍射、扫描电子显微镜和全自动矿物学 QEMSCAN 分析，以全面了解英格兰西北部雷文格拉斯河口冰后碎屑沉积物中的矿物成分和分布。雷文格拉斯河口由两条主要河流注入：一条河流流经以花岗岩为主的腹地，另一条河流流经含有安山岩和三叠纪红层砂岩的腹地。与安山岩和红层提供的沉积物相比，花岗岩提供的臂具有稍微更多的富含石英和贫铁矿物的沉积物。长石和云母矿物的来源信号减弱，重矿物石榴石群体似乎对来源敏感。碎屑钾长石颗粒优先与以伊利石为主的粘土矿物层伴生，而所有斜长石矿物颗粒优先与以高岭石为主的粘土矿物层伴生。这可以通过沉积物中的快速早期成岩作用来解释，钾长石颗粒表面被伊利石取代，斜长石颗粒表面被高岭石取代。安山岩和红层沉积物含有的铁矿物含量是花岗岩沉积物的两倍，其中铁矿物主要是绿泥石。绿泥石很少与长石颗粒上的颗粒涂层相关，可能是因为它主要是一种碎屑矿物。由于细菌硫酸盐还原作用，碎屑铁矿物似乎局部被黄铁矿取代，这表明一些早期成岩过程可能会锁住铁并防止其形成富铁粘土矿物。
Abstract The occurrence and distribution of minerals in modern sedimentary systems hold many clues to help unravel the origin and distribution of reservoir quality-controlling minerals in ancient and deeply buried sandstones, but few quantitative studies have been undertaken. Here we have used a range of techniques including X-ray diffraction, scanning electron microscopy and fully automated mineralogical QEMSCAN analysis to provide a comprehensive understanding of mineral composition and distribution within the post-glacial, clastic sediments of the Ravenglass Estuary, NW England. The Ravenglass Estuary is fed by two main rivers: one drains a granite-dominated hinterland, the other drains a hinterland that contains andesite and Triassic red bed sandstones. The granite-supplied arm has slightly more quartz-rich and Fe mineral-poor sediment than the andesite- and red bed-supplied sediment. The provenance signals are muted for feldspar and mica minerals heavy-mineral garnet populations seem to be sensitive to provenance. Detrital K-feldspar grains are preferentially associated with illite-dominated clay mineral coats, whereas all plagioclase mineral grains are preferentially associated with kaolinite-dominated clay mineral coats. This can be explained by rapid early diagenesis in the sediment with K-feldspar grain surfaces replaced by illite and plagioclase grain surfaces replaced by kaolinite. The andesite- and red bed-supplied sediment contains twice the amount of Fe minerals, which are dominated by chlorite, than the granite-supplied sediment. Chlorite rarely is associated with grain coatings on feldspar grains, possibly because it is predominantly a detrital mineral. Detrital Fe minerals seem to be locally replaced by pyrite due to bacterial sulphate reduction, suggesting that some early diagenetic processes may serve to lock away iron and prevent it from creating Fe-rich clay minerals.
花岗岩结构参数对沉积物成分的影响：对沉积物生成的影响
影响因子：
2.8
作者：
Caracciolo L;Tolosana-Delgado R;Le Pera;von Eynatten H;Arribas J;Tarquini S
通讯作者：
Tarquini S