摘要
信都组粉砂岩中存在着菱铁矿质的两种鲕粒和一种由菱铁矿、绿泥石与碎石英砂组成的复成分豆粒。鲕粒具同心层放射状构造。无论在粉砂岩中,还是在鲕粒与豆粒中,菱铁矿和绿泥石均不属原生沉积矿物,而是同生和成岩矿物。由菱铁矿和绿泥石组成的鲕粒与豆粒,也不是原生沉积的,而是同生和成岩的产物。
There occur two kinds of oolites composed of siderite and a kind ofpolymineralic posolite composed of siderite, chlorite and quartz in thesiltstone of Xindu Formation, Middle Devonian. The oolite is characteristicof concentric laminar and radiative structure. Siderite and chlorite aresyngenetic and diagenetic minerals, but not syndepositional ones both in thesiltstone and in its oolite and posolite, So are the oolite and posolite composedof such minerals.
关键词
粉砂岩
鲕粒
豆粒
信都组
泥盆世
siltstone
Xindu Formatim
Middle devonian
Wuzhou/oolite
posolite
