A Study On The Triassic Hydrogeological Characteristics Of The Western Of Sichuan Basin And Calculating The Brine Resources

This paper studies the Triassic Hydrogeological characteristics of theWestern ofSichuan Basin and calculates the brine resources.This article is on the base of thecollection and summary of the physical geography, lithology, regional geologicstructure and hydrogeological profiles.This article summarizes and analyzes the characteristics of71folds and41faultsof the Western of Sichuan Basin. The distribution of structures which are stronglyaffected by Longmen Mountain is mainly along the northeast.The majority ofstructures are low anticlines. By collecting and sorting interpret seismic datas and94drilling datas of the Western of Sichuan Basin, and selecting the representativedrillings datas of pingluo4wells,pingluo20wells and fenglu1wells,this paperresearches the properties, lithology, brine storage media types, and control structuralfeatures of the Potassium-rich brine reservoir of Leikoupo.This article analysises the water chemistry datas of17drillings of theWestern ofSichuan Basin, and compares the Potassium-rich brine of the Western of SichuanBasin with the Potassium-rich brine of foreign, the East and middle of the SichuanBasin,it believes that chemistry characteristics of Potassium-rich brine in the Westernof Sichuan Basin is rich in salinity, potassium, boron, iodine, strontium, lithium,rubidium, magnesium and other useful components, poor in magnesium and sulfate.Through the above analysis, the western area is divided into three geochemicaldynamics zones: Water oxidation zone with alternating smooth, Water redox zonewith alternating slow and Water reducing zone with alternating blocks.The Leikoupo Lithofacies palaeogeography maps of the Western of SichuanBasin are modified in this paper. The evolution of Lithofacies palaeogeographyperformances that from the one to four period of Leikoupo, the depositionalenvironment experiencs the gradually deepening water, shallow and further deepen. Itis proposed that Triassic Leikoupo of the Western of Sichuan Basin can be devidedinto three Hydrogeological periods, the first period is the Leikoupo depositionleaching period,the second period is the continental burial period from the late Triassic to the late Cretaceous, the last period is tectonic period from the lateCretaceou to now.Basing on the carbonate rocks consolidation mode of action of the upper Jurassicanticline in Muda Li Ai Taiwan, this paper restores and reconstructes the TriassicLeikoupo’ palaeohydrodynamic field of the Western of Sichuan Basin, and drawes thefigure of the hydrodynamic field of the Western of Sichuan Basin.The Potassium-rich brine distributes in the Triassic Leikoupo of the Western ofSichuan Basin’s one,three and four periods, this article combines the feature of thePingluoba brine storage structure, delineates13major enriched brine structures of theWestern of Sichuan Basin, including Ping Luoba structure,Han Wangchangstructure,Dayi structure,Da Xingchang structure,Yan Jinggou structure,TuoBachang structure,Wen Xingchang structure,Lao Guanmiao structure,Da Liangzistructure,Fu Shunchang structure, Xinchang structure,He Xingchang structure andGu Jingba structure.This article uses volume method to calculates the Potassium-rich brineresources of the Western of Sichuan Basin, there are11.5341million tons in theSouthwest of the Sichuan Basin, and2.97million tons in the Northwest of theSichuan Basin, The analysises suggest that the forming of the Potassium-rich brine ofthe Western of Sichuan Basin experiences deposition, leaching, burial, tectonichydrothermal periods,and so on.