Analysis The Souces Of System Of Qikou Depression Area Es₃

Qikou depression is located in the Bohai Bay Basin in northern Huanghua depression, the third series of inherited development of large hydrocarbon rich depressions (Dagang Exploration Area, exploration area)5280km2, rich oil and gas resources, is the oil in the oil and gas exploration in one key area.Qikou SagNeogene tectonic layer.Which block fault upwarping movement significantly, lacustrine facies deposition to create various types of sand body development, structural sandbody matched for oil and gas accumulation with superior reservoir space.Qikou Sag sand three section of sedimentary facies, sand body distribution, source system, based on the hierarchical system of comprehensive evaluation of the reservoir, clear reservoir factors and favorable reservoir sand bodies distribution regularity, provide the basis for exploration decision.So the source system of comprehensive evaluation of the reservoir is one of the foundation work.Shahe Street group of three during the depositional period of several faults are from this area through, lacustrine facies sand body development, other genetic types of sand bodies is numerous, complex geomorp ho logical features.In this way, both to increase the source of complexity, but all related, and can use a variety of phenomena, characteristics analysis for source information.Es. consists of two order sequences, we study the sand three section is divided into3level three sequences and8four order sequences.The isochronous stratigraphic framework, with three order sequence units, and four order sequences in Qikou depression Es. provenance system research.Will combine the sand three deposition period of tectonic movement, water flows through the clasts, variation characteristics, heavy minerals composition variation and sand body in the recess of the dispersion system changes, that several major source area roughly distribution, the distribution range and lithologic features.We will focus on in this region, a comparison of two representative districts:Banqiao concave, Qibei slope belt. In the two regions respectively represent the two typical characteristics.Such as, Panchiao concave in the ancient water system in the ancient river, river office.Granular points selection, relatively poor, coarse particles; Qibei slope belt in the river, branch selection is better, the particles with smaller.The source also is one of the major characteristics of buried depth, according to logging data shows, Shahejie group average formation in3000-4000M.Shahejie sedimentary period, a plurality of breaking through the area, the whole sag in the north is Yanshan fold belt, Western Cangxian uplift, to the south of Kongdian-Yang Miki Qianshan, to the East is the main concave qk.Analysis of stable heavy mineral in different location on the change rules of the content, largely determine the source direction and range; also use light mineral the unstable ingredient in feldspar, quartz or stable mineral composition, judge the direction of source; detrital composition maturity, structure to read; sandstone percentage distribution range, as well as variations of these methods to the analysis of the source.