Stratum Framework And Distribution Characteristics In The Eastern Area Of Linqing Depression

Linqing Depression is a composite fault basin in Meso-cenozoic, affected by superposition and reconstruction of multiple phase tectonic movements, the characteristics of layer and distribution very complex. In addition, the bases researched by predecessors are weakly, so clarify layer framework and distribution characteristics of every structural layers is very important, and it's the base of hydrocarbon resources evaluation and prospecting in this area. On the base of researches of predecessors, first of all, this thesis divided structural layer utilized a great quantity of seismic cross sections and acoustic log, afterwards, by means of description and summing-up of lithology, palaeophyte, log and seismic facies characteristics, sum up the recognition criteria of layer vertical partion, established layer framework in this area, and, choose many connected well profiles make lateral correlation about structural sub-layer, analysed the distribution characteristics of relict layer about every structural sub-layers in this area. On the case eastern area of Linqing Depression, the fault is the most main tectonic movement in Meso-cenozoic, on the basis of research in the fault development and combined characteristic, union the reaserch of vertical growth of synthem and the crosswise mop, have analyzed the control action fault activity to the distribution characteristic.Researches show that, overall stratum growth entire in eastern area of Linqing Depression, divides from bottom to top into four synthems: basal synthem, Paleozoic synthem, Mesozoic synthem and Cenozoic synthem. Basal synthem is the Taishan mountain group in archaean, is mainly the gneiss; The paleozoic synthem besides the regional lost stratas: Upper Ordovician, Silurian-Devonian and Lower Carboniferous, other stratas have the distribution, divides into Cambro-ordovician and Permo-Carboniferous two structure subgroups. Cambro-ordovician is a set of carbonate construction, Permo-Carboniferous system is a set contains the coal clastic rock deposition; In the mesozoic synthem lost Upper Triassic and Upper Crataceous ,growth Middle-Lower Triassic and Middle-Lower Jurassic and Lower Crataceous three structure subgroups, main growth varicolored land facies clastic rock, discovered rich fossil data such as cryptogam ,Ostracoda and Chareae and so on. Lithologic character of Eogene syste is interbedded sandstone and mudstone primarily, including the thin layer oil shale, Neocene- Quaternary system is set of rivers deposits. Based on this, through the reaserch of ateral correlation and distribution characteristics of every structural layers show that: Paleozoic synthem overall thickness of relatively stable.The residual thickness of Mesozoic synthem is difference in the horizontal, Residues in the horizontal thickness of greater difference, to the greatest thickness achieve to 4500m. Eogene syste has obviously fault depression basin deposition characteristic, the thickness of many sags achieve to 3000 m ,from Neocene, the stratum crosswise mop tended to be stable. Looking from various synthems stratum mop characteristic, the Meso-cenozoic fault activity is the important control action to the deposition and the denude of Late Jurassic- Early Crataceous and Eogene.