| The Fuyu reservoir in Chaoyanggou oilfield belongs to the deposit of the lower super-sequence in the lower domain,which is mainly composed of shallow lake and delta sedimentary system.The main reservoir of Fuyu reservoir belongs to the low porosity and low permeability reservoir,which is composed of multi-stage channel superimposed.There are some problems,such as small channel scale,thin sand body and fast phase transformation,leading to poor development effect.In terms of structure,Block X of Chaoyanggou oilfield is located at the edge of anticline,and the relationship between oil and water in the favorable area of outward expansion is complicated.The reservoir sand body controls the formation of "one sand and one reservoir",and the hydrocarbon accumulation is greatly affected by the distribution of sand body.This study takes the FI reservoir group and FⅡ reservoir group of Block X as the research object.Based on the previous research results,comprehensive use of geological,seismic and logging data,under the guidance of seismic sedimentology and other theories,seismic attribute analysis technology and geostatistical inversion are used to analyze the sedimentary microfacies in the study area,combined with the traditional logging facies model.Complete the drawing of sedimentary microfacies map and describe its spatial distribution characteristics;Then the distribution law of oil and water is studied,and the controlling effect of sedimentary microrelative is defined.Finally,the scope of favorable well distribution is implemented and well location is deployed.The results show that:(1)The instantaneous amplitude attribute is the most favorable to reflect the lithologic assemblage information and the most obvious to reflect the transverse band changes.The RGB multi-attribute fusion technology is more effective to identify narrow and thin channel sand bodies.Deep lateral resistivity inversion can delineate channel boundary more clearly and distinguish sand and mudstone well.(2)Following the principle of "giving priority to channel characterization",the sedimentary microfacies characterization method of "well point microfacies control channel number in dense well pattern area,sensitive attribute control trend in outer expansion area,supplemented by inversion profile as reference" was established,and the sedimentary microfacies maps of 13 sedimentary units were completed.(3)According to the trap and fault characteristics,the study area can be divided into four fault blocks,and the reservoir types can be divided into fault-lithologic reservoir and structure-lithologic reservoir.The oil and water characteristics of the outward expansion area are analyzed,and the favorable oil bearing areas of each fault block are determined.(4)According to the distribution characteristics of oil and water,it is concluded that the oil reservoir is mainly developed in FⅠ5,FⅠ7 and FⅡ1.Based on the data statistics and three sedimentary units as examples,it is clear that the oil enrichment is mainly controlled by various channel sand bodies,and the oil and gas are distributed in patches and strips along the channel direction.At the same time,the deposition exerts a strong control over the distribution of oil and water.(5)According to the structural conditions of each fault block,sedimentary microfacies type and oil-water distribution relationship,the main layers were selected,and the main layers were superimposed with sedimentary facies,and the parts of channel sand bodies developed and multi-stage superimposed in the favorable area of the reservoir were delineated as the favorable area of outward spreading well.After comprehensive evaluation,4 favorable areas of 3types of outward spreading well were selected,and then the first drilling was deployed. |
