Fine Reservoir Description Of 4-6 Area Of HDD Oil Field

HDD Oil field has been mined over a decade,the previous made some geological tracking research work to this area of condensate oil reservoir,for example:accumulation of geological conditions,structural geology characteristics,the sedimentary facies,the reservoir heterogeneity,oil reservoir geological modeling,etc,and had acquired great success and breakthrough.However with the gas field to further develop and acquire more data,new problems appear constantly,mainly in the following areas:The interlayer are more developed in the study area,but the existing achievements are more limited understanding on the interlayer,lack logging identification standard bout theinterlayer in the study area;Existing studies didn't effective use of the dip log datas;There are several new wells in the study area,we should add them into the geological modeling and adjust it.In order to achieve sustainable yield,control water content,stable oil content and deepen understand of reservoir geology,fine reservoir description is imperative to carry out.In the paper,we combining the geological characteristics of HDD oil area and integrated using various types of Exploration and development data,in this paper we divided the small layer of DongHe sandstone,studied the sedimentary,interpreted the reservoir parameters,identified interlayer,researched on the reservoir characteristics,builded reservoir geology mold,comprehensive evaluation of the reservoir,has achieved the following results:Using the principles of high resolution sequence stratigraphy,and combining core and logging data,we identified one sequence,two parasequence and fourteen small layer on the Donghe sandstone reservoir in study Area.Horizontally,from the north west to south east,Donghe sandstone thickening after the first thinning,from south west to north east donghe sandstone gradually thinning;plane,the donghe sandstone was distributed south thick and North thin characteristics.The under donghe sandstone was deposition towards the coast r for sea level rise,and the upper donghe sandstone was deposited seaward for sea level fall.Combining with regional sedimentary background,basing on core observations we determined the processing parameters,used long and short window length relevant comparison.Using core datas correspond to the short window handle results,we established 10 bedding dip Angle models of the study area.Combining core,logging data and dip interpretation results,and combining with regional geological background,we can think that the sedimentary facies is no barrier wave accused of sandy transgresive deposits in the Donghe sandstone reservoir.We divided the ransgresive deposits into coastal dunes,backshore,foreshore and shoreface four Subfacies.foreshore and shoreface are the major facies in the study area,and they are mainly in the middle of Donghe sandstone,backshore facies mainly distributed in the upper and lower of Donghe sandstone.Basing on physical properties data of core analysis,using neural network we interpreted porosity and permeability of the study area secondly,the results are more accurate than the results of previous.Through the statistical analysis of area core,logging,test oil of the area,we found that porosity and permeability,we found that the sandstone is mainly to fine-grained sandstone,the average content is 64.65%,the second is minddle-sandstone.Reservoir properties mainly with middle porosity and medium-high permeability,porosity with an average 15.43%,permeability with an average of 186×10^-3?m².The highest percentage of the oil level is Oil invasion.Four-property relationship is more coarse rock,higher the level of oil,and better physical properties in the study area.According to core observation,core date and petrographic thin sections of the study area,the interlayer of the study area will be put into three categories:interlayer of calcareous sandstone,interlayer of laminated shaly calcium and interlayer of laminated shaly.Through the three types of laminated electrical response of cluster analysis,we establish criteria to identify three types of interlayer.The interlayer mainly in 5,6,7,8layer,and had Larger distribution range.In 1,2,11,12layer the interlayer small distribution and thickness is thinner.Horizontally,the interlayer poor continuity;On the plane,the interlayer are located in the northwest and southeast,and less in the Northeast dissection.Combining Geological characteristics of the study area,using geostatistical methods,basing on the program of 14 layers and 13 interlayers,we builded the structure model of the study area.Then builded porosity model,permeability model and water saturation model of the study area by sequential Gaussian simulation method,of District porosity use sequential Gaussian simulation method,spatial distribution of reservoir parameters.According to the date collected of the study area,using test oil,experience statistics and minimum flow radius of pore throat method,we determined the donghe sandstone porosity bottom limit was 8%and permeability bottom limitwas 5×10^-3?m².Combining reservoir porosity characteristics of the study area,we putted the reservoir into three categories and established reservoir classification criteria of the study area.Class?reservoir are mainly in the upper of donghe sandstone.Class?reservoirs are located in the middle of the donghe sandstone,Class?reservoirs are located in the upper and lower sections of the donghe sandstone with relatively poor connectivity;On the plane,class?reservoirs are located in the western and southeastern well area,class?reservoirs are mainly distributed in the central and northeastern areas well,class?reservoirs are mainly distributed in the southern district well.Reservoir development was remarkably controlled by sedimentary facies,class?reservoirs and class?reservoirs are mainly developed in foreshore and shoreface facies,class?eservoirs are mainly developed in backshore facies.