贵州天鹅山下寒武统黑色岩系化学地层初步研究

华南下寒武统黑色岩系“多元素富集事件”受世人瞩目。贵州遵义天鹅山下寒武统牛蹄塘组剖面的元素地球化学测试表明,黑色岩系存在贵金属元素、稀土元素及其他微量元素的异常富集,绝大多数较上覆、下伏地层含量为高。元素地球化学特征显示,元素的来源并非地外,而是海底含矿热卤水沿深大断裂而来,“热”的来源为地内火山喷溢。黑色岩系形成时期的沉积环境为一种干燥气候的较深浅海的还原环境。据古地温判定,黑色岩系属低温成岩成矿作用。

STUDY OF CHEMICAL STRATIGRAPHY OF THE LOWER CAMBRIAN BLACK SHALE SERIES IN TIAN'ESHAN SECTION OF ZUNYI, GUIZHOU

People have paid great attention to the “many elements-enriched event” in the Lower Cambrian black shale series in south China. Elemental geochemical determination has revealed anomalies of noble metal elements, REE and other trace elements in the Lower Cambrian black shale series in Tian'eshan section, (Zunyi), Guizhou, which have relatively higher contents than those in its overlying and underlying beds. Characteristics of elemental geochemistry demonstrated that the elements were derived from hot bittern seawater sediments from magma, and high enrichments of elements resulting from the mixing of hot bittern seawater sediments and normal seawater sediments, and not caused by extraterrestrical impact event. The sedimentary environment at this period was an reducing epeiric sea environment.