Provenance Analysis And Sedimentary Facies Of Paleogene And Neogene In The Eboliang Area Of The Northern Qaidam Basin

This paper based on Paleogene and Neogene of Eboliang area for the study in the northernmargin of the Qaidam Basin, including the tectonic belts of Eboliang Ⅰ, Eboliang Ⅱ andEboliang Ⅲ and the surrounding belts such as Dongping tectonic belts, Lenghu tectonic zones,Yahu tectonic belts, Nanbaxian tectonic zones. The area of drilling cores, sections and theperipheral Laoshan carried out a detailed observations and descriptions, and sampling andanalysis. Collecting logging drilling datas and interpretation of the study area in three finishingwork area dimensional seismic datas, combined with previous researches in all aspects of datadepositions, structures, reservoirs and parent sources, for a more detailed provenance directionanalysis and sedimentary facies analysis. Get the following major achievements andrecognizes.（1）Depended on mathematical statistics of Q-typecluster, correlationanalysisandZTRindexes to ensure the direction of the parent sources in heavy minerals. The combination oflight mineral analysis, lithic analysis, CL analysis, REE analysis and seismic analysisconducted a comprehensive analysis on Paleogene and Neogene of Eboliang area for a detailanswer in the northern margin of Qaidam Basin. The three tectonic belts of Eboliang haveeffected by different provenances. The parent sources of Eboliang Ⅰis gotten from the westdirection of Altyn. The parent sources of Eboliang Ⅱ is a commonly affected by both sourcesof Altyn and XiaoSaishitengshan. The parent sources of Eboliang Ⅲ is gotten the northernmountains of Saishiteng through the sixth and seventh tectonic belts of Lenghu.（2）Base on sections and drilling cores for observation and description, logging andseismic data for a comprehensive analysis, to establish sedimentary facies identification flagson Paleogene and Neogene of Eboliang area, there are five kinds of sedimentary facies types,such as alluvial fan, fan delta, braided river, braided river delta and lake. And to build two kindsof deposition patterns in the study area, the steep slopes with near-source and the gentle slopeswith the far-source. （3）The Eboliang area of Paleogene and Neogene has two kinds of deposition patterns.One is the deposition of steep slopes with near-source by alluvial fan, fan delta and lake in theEboliang Ⅰ, Eboliang Ⅱ and the Lenghu area. The other is the deposition patterns of thegentle slopes with the far-source by alluvial fan, braided river, delta and lake in the sixth andseventh tectonic belts of Lenghu, Eboliang Ⅲ and the area of Nanbaxian.（4）Through the preparation of sand thickness contour, seismic facies distribution andother infrastructure, on Eboliang area of Paleogene and Neogene sedimentary evolution for adetailed analysis, to prepared the Lulehe formation to the Shizigou formation relative to thesedimentary facies plane distribution Figs. Micro-focus distributions have detailed analysis onEboliang Ⅰ and Eboliang Ⅲ in some important parts of the sedimentary.