摘要
前人对神农架群巨厚层白云岩的成因尚存争议,笔者从沉积岩地球化学入手,探讨神农架隆起南缘神农架群石槽河组白云岩的成因。石槽河组白云岩的岩石学特征显示以泥—粉晶白云岩为主,多具纹层状。地球化学上,V/Cr、Ni/Co及V/(V+Ni)值表明了其沉积环境具有氧化性,稀土元素基本保留了海水来源REE特点,同时在成岩改造中可能是受到热液作用的影响。岩石学和地球化学特征表明石槽河组白云岩可能是在潮坪环境下强烈蒸发作用形成的。
The origin of thick dolomites from Shennongjia Group is quite difficult to solve in long term,and the research on dolomite genesis is in postulation at present.Based on the study of geochemistry of sedimentary rocks,the paper dis-cusses the origin of Shicaohe dolomite from Shennongjia Group at southern Shennongjia uplift.The types of dolomites in-clude putty crystal dolomite and powder crystal dolomite primarily,and they possess the characteristic of laminated struc-ture.The ratios of V/Cr,Ni/Co,V/（ V＋Ni） of Shicaohe dolomite show that it formed in an oxidation environment. REES have the basic characters of the rock from seawater.Besides that,it can be influenced by hydrothermal fluid on the later diagenesis.Based on petrological and geochemical characters,intense evaporation in tidal flat environment may form Shicaohe dolomite.
出处
《资源环境与工程》
2016年第4期551-555,共5页
Resources Environment & Engineering
基金
中国地质调查局基础地质调查项目(编号:1212011220509)资助
关键词
石槽河组
白云岩
地球化学
神农架群
Shicaohe formation
dolomite
geochemistry
Shennongjia Group
