Discussion on the geological features and sedimentary environment of the Early Carboniferous Jiujialu Formation in Jinsha area of central Guizhou
There are abundant bauxite and ceramic-making claystone resources with advantageous and developmental potential in the central area of Guizhou Province.Through the research into the route sur-vey,section measurement and mineral identification on Jiujialu Formation in Datang age of GuiZhou Prov-ince,in combination with the analysis of paleoenvironment by finger trace element,the findings firstly il-lustrate that:the microscope observation on this strata of rocks shows vadose pisolith structure of the alu-minous clay rocks,isocrystalline structure of the siliceous rocks and micrite-cluster structure of the ferrag-inous rocks,suggesting a characteristic of continental sedimentary environment in the study area,mean-while,the rock type and lithology combination characteristics roughly reflect that the whole area is terrige-nous clastic deposition under the settings of the reducing environment and low energy hydrodynamic.Sec-ondly,the Th/U ratio indicates that the clay rocks of Jiujialu Formation in the Datang age are basically formed in a weak oxidation environment,and with the rising ratio during the deposition process,the oxi-dation gradually strengthened at the same time.Lastly,the values of facies element B,Sr and Ba,and the ratios of B/Ga and Sr/Ba indicate that the clay rocks in the Datang age of Jiujialu Formation underwent several transgressions stages and regressions stages in the Early Carboniferous,and eventually turned into a continental environment.It is inferred that Jiujialu Formation in the Datang age of Early Carboniferous in Jinsha area was located in the epicontinental sea zone.As constrained by the shape and position of the palaeokarst and the direction of seawater influx,Jiujialu Formation in Jinsha area appears complex sedi-mentary characteristics in different areas.
Jinsha in central GuizhouEarly Carboniferousaluminum-bearing rock seriesJiujialu Formationsedimentary environment
万方数据
维普
