广西横县六景中泥盆统Mg、Ca、Na、Sr、δ^(13)C和δ^(18)O化学地层学特征  

CHEMOSTRATIGRAPHY OF Mg,Ca,Na,Sr,δ^(13)C,δ^(18)O IN MIDDLE DEVONIAN STRATA OF LIUJING SECTION,GUANGXI

作　　者：刘疆[1,2] 白志强[3] 

机构地区：[1]海南省地质勘查局 [2]海南省海洋地质调查局,海南海口570206 [3]北京大学地球与空间科学学院,北京100871

出　　处：《物探与化探》2009年第4期417-423,共7页Geophysical and Geochemical Exploration

基　　金：国家自然科学基金项目(40372018)

摘　　要：广西横县六景中泥盆统的Mg、Ca、Sr、Na、1δ3C和1δ8O化学地层特征清晰地量化了该剖面的岩相及其变化规律,并在生物地层框架内,使该剖面的高精度划分和高精度区域性对比成为可能。化学地层数据与该剖面的沉积相和生物相之间存在良好的对应关系,显示那叫期的中泥盆统段为滩后泻湖与蒸发滩3次交替沉积环境;民塘期至谷闭初期为碳酸盐礁滩后斜坡沉积环境。那叫组白云岩的化学地层数据显示不能简单排除白云岩的化学地层学研究价值,可以对成岩作用较弱的细晶、粉晶白云岩,尤其薄层、纹层白云岩开展适度的化学地层学研究。Chemostratigrphil characteristics of Mg, Ca, Sr, δ^13C and δ^18O can clearly quantify lithofacies of Middle Devonian strata along the Liujing section. Within the biostratigraphie framework, these characteristics make possible the high-resolution partition and regional high-resolution correlation of the Middle Devonian strata. The sedimentary environment of Middle Devonian Najiao Formation is characterized by three times of alternate shoal-rear lagoon and vaporizing foreshore, and that of Mintang Formation and Lower Gubi Formarion is the reef-rear slope. These chemostratigrphic characteristics are consistent perfectly with those of sedimentary facies and biofacies. Chemostratigraphic data of Najiao Formation also show that dolomite should not be hastily excluded from the chemostratigraphic study. The fine-grained dolomite and powder crystal dolomite, especially the thin-layered and laminated dolomite, deserve further proper studies.

关 键 词：广西 六景 中泥盆统 Mg CA SR NA δ13C δ18O 化学地层 

分 类 号：P632[天文地球—地质矿产勘探]