摘要
华南下寒武统黑色岩系Ni-Mo-PGE序列富硫化物层上、下均出现在区域上延伸不甚稳定的硅质岩，过去对其支因未作研究。该硅质岩在刘峋峰（1994）的化学成因、生物成因和火山成因硅质岩氧化物（SiO2－Al2O3、SiO2－MgO、SiO2－K2O＋Na2O）判别图解上多落在化学成因区和火山成因区；在Wonder的热水成因和正常水成因硅质岩SiO2－Al2O3判别图解上，多落在热水成因区。该硅质岩稀土总量低，北美页岩标准化曲线见明显Ce负异常且略向左倾。其微量元素MO、Zn、As、Sb、Se、U浓集系数高，Ba较非热水沉积物富集，U／Th≥1。综合上述特征，参考李胜荣（1994）有关的其他研究成果，本文认为该硅质岩系汲取了海底岩浆岩组分的热卤水活动产物。
A silicalite bed was found in the hanging wall and f00twall of the sulfide-rich bed of theLower Cambrian black rock series of South China. lts origin has not been studied before. On theoxide (SiO2-Al2O3, SiO2-MgO, SiO2-K2O+Na2O) diagrams discriminating silicalites of chemical,biological and volcanic origins, most of the silicalite composltion points fall within the areas representing silicalites of chemical and volcanic origins. On the SiO2Al2O3 diagram discriminating silicalites of hydrothermal and hydrogenous origins, the composition points are mostly plotted withinthe hydrothermal area. The total amount of rare-earth elements of the silicalite is low; the rareearth element cufrves normalized by North American shales decline left with obviously negative Ceanomaly. The trace elements Mo, Zn, As, Sh, Se, U are richer than those in the earth's crust,Ba is richer than that in non-hydrothermal sediments, and U/Th≥1. The present authors thinkthat the silicalite is the product of seafloor hot brine absorbing elements of igneous rocks.
出处
《矿物学报》
CAS
CSCD
北大核心
1996年第4期416-422,共7页
Acta Mineralogica Sinica
基金
国家自然科学基金
中国科学院矿床地球化学开放实验室基金
中国博士后科学基金
关键词
硅质岩
热水
黑色岩系
成因
silicalite
hot brine
black rock series
Lower Cambrian series
South China
