摘要
皖南上震旦统兰田组中发育一套黑色页岩,富含炭质、自生黄铁矿丰富,具细的水平纹层,属于缺氧环境下的沉积物。本文讨论了黑色炭质页岩的地球化学特征,认为 Mo/Mn 比率是判断缺氧环境的良好标志,缺氧和含氧界面的 Mo/Mn 比率是0.005—0.01,缺氧环境中的沉积物,Mo/Mn 比率大于0.005—0.01;含氧环境中的沉积物,Mo/Mn 比率小于0.005.此外,v/Ni 比率在缺氧与含氧环境中形成的沉积物内也有明显的差异。缺氧环境下的沉积物中,v/Ni 比率大于3,而含氧环境下形成的沉积物中,v/Ni 比率多小于3。
In the upper Sinian Lantian Formation a suite of black laminated shale rich in carbon and authigenic pyrite is the sediment under anoxic environment.This paper discusses the geochemical characteristics of the black carbonaceous shale.It is held that the Mo/Mn ratio of sediment is a good in- dex to determine the diagenetic environment.The Mo/Mn ratio of the interface of anoxic and aerobic environment is 0.005—0.01.Mo/Mn>0.005—0.01 indicates anoxic and Mo/Mn<0.005 indi- cates aerobic environment.V/Ni ratio is another environment index.V/Ni>3 shows anoxic and V/ Ni<3 shows aerobic.
出处
《安徽地质》
1993年第3期16-21,共6页
Geology of Anhui
关键词
晚元古宙
上震旦统、黑色页岩、缺氧环境、地化特征
皖南
Late Proterozoic
Lantian Formation black shale
anoxic environment
geochemical characteristics
South Anhui
