鄂西地区泥盆系-石炭系泥质岩沉积地球化学特征及沉积环境研究

对湖北省长阳县火石山泥盆系黄家磴组-石炭系高骊山组21块泥岩样品的地球化学特征分析表明,黄家磴组、梯子口组、高骊山组的SiO2和Al2O3及TFe2O3的含量较高,表明受陆源物质影响较大;和州组下段CaO含量高,表明海水相对较深。Na2O及Mg/Ca值指示气候经历了温湿-干热-温湿变化的过程。微量元素,如Cu、Pb、Z...

Geochemical Characteristics and Sedimentary Environment of Devonian and Carboniferous Mudstones in western Hubei Province

The geochemical characteristics of twenty-one samples from the Devonian Huangjiadeng Formation to Carboniferous Gaolishan Formation at Huoshishan section,Western Hubei are studied.The high content of SiO2,Al2O3,TFe2O3 of Huangjiadeng Formation,Tizikou Formation,Gaolishan Formation,indicated they had been greatly influenced by the terrigenous resource,while the high content of CaO of the lower part of Hezhou Formation indicated that the sea water is relatively deep;the content of Na2O and the ratio of Mg/Ca means that climate experienced the process from warm and wet,to dry and hot,and to warm and wet.The trace elements change curve is consistent with high amount of REE,obvious differentiation of ∑LREE and ∑HREE and negative Ce and Eu abnormities.The similar curve of REE means all the samples are from the same origin.Cu/Zn,V/Cr,Ni/Co,U/Th,Uau and the Ce/La ratios indicate that the research area as a whole had been under an oxidized environment,while Sr/Ba and B/Ga ratios tells that they have been deposited nearshore.The mathematics statistical analysis results indicate that samples from similar sedimentary environment and hydrodynamic condition share the similar geochemical characteristics;correspondingly,those which are different from obvious different deposition environments.The delta facies shows similar geochemical characteristics with those different sedimentary environments can be explained as that it as a whole was in an area of flood and field alternately existed where the environmental variation was great.