The Thin And Poor Pay Zones Effective Producing Limitation And Technology Policy Limitation Research On Xing-6 Blocks Of DaQing Oil Field

The interior of Daqing placanticline oil field has already entered the period of high water cut,with the deepening of oil and gas field development technology,the current water flooding development objects in the high and moderate permeableness layers gradually transformed into poor thin layers,such reservoirs with the complicated structure have poor development benefits,but the remaining reserves of several million tons of the demonstrated reserves mainly exist in low permeability poor thin layers.Since the 1960s,the Xing-6 Blocks have spaced four well patterns,which are basic well pattern,first infill well pattern,secondary infill well pattern and tertiary infill well pattern,of which the secondary and tertiary infilling pattern are mainly for the thin and poor pay zones,and the tertiary readjustment wells have not yet been fully put into production.After secondary infill adjustment,the development effect has been significantly improved,but currently the development well pattern deployment of thin and poor pay zones still have the problems of the imperfectly injection-production relation,poor water flooding wells driving,and low producing degree,and it is still difficult to employ the untabulated reservoirs with poor development.In order to improve the effect of oil development,and enhance the producing degree of low poor thin reservoirs with permeability and poor physical property,so that it can establish the effective driving energy system,the research on effective producing limitation and technology policy limitation of thin and poor pay zones need to strengthen.Through a lot of research abroad effective producing and rational development technology policy limitation research results on the thin and poor pay zones,based on the basis of previous work,the paper study the microscopic pore structure of thin and poor layers,and compares with the thick reservoirs,while carrying out the research on effective producing limitation and development technology policy limitation of thin and poor layers.Taking Xing-6 Blocks of DaQing Oil Field as the research object,the paper firstly study the geological characteristics and reservoir properties,analyzes reservoir structure,fault characteristics,geological development and physical property characteristics.Through the laboratory routine pressured-mercury testing and rate-controlled mercury penetration experiment,the paper compared the microscopic pore structure characteristics of different types reservoirs,primarily including the core pore size,throat radius and pore throat ratio,and adopted the normalized capillary pressure curve to contrast physical property differences of tabulated thick reservoirs,tabulated thin reservoirs and untabulated reservoirs,also analyzed the microscopic pore structure parameters that influence the producing degree of different types of reservoirs According to the watering-out data of coring wells,the paper evaluates the reservoir producing condition of thin and poor layers,analysis influence factors of degree of developed producing reserves on thin and poor layers,including reservoir properties and development factors,and determined the upper producing limit of permeability by pressure method and nonlinear flow index method,the lower contrast limit based on the laboratory parallel two transistors testing,and the lower pore throat mobilization is determined based on the NMR experiments.Combined with reservoir engineering methods,the reasonable well pattern density and spacing is determined,and the middle area of Xing-6 Blocks' 3D geological model is established,and the numerical simulation is studied.On the basis of the standard model fitting accuracy,the paper analyzed the plane and vertical distribution characteristics of the remaining oil,the untabulated reservoirs independent development studies,and also discussed the potential and the corresponding boundary of the stimulation treatment.Studies show that:the tabulated Xing-6 Block reservoirs have a better watering-out condition,and with the increasing sandstone thickness,the developed producing reserves increase,there are still a considerable portion of unproducing reserves of untabulated reservoirs after the secondary infilling.Permeability,oiliness,thickness and the type of thickness,reservoir heterogeneity,sedimentary facies distribution,injection-production type,interlayer interference and well pattern and spacing all have the influence on effectively producing of the thin and poor layers.The permeability lower producing limit of the Xing-6 Block's thin and poor layers is 1×10-3?m2,the effectively producing upper contrast limit of the thin and poor layers is 5,and the mean flow pore throat radius limit is 0.288?m.The reasonable well spacing density of the Xing-6 Block is 32.85/km2,and reasonable well spacing is 156 to 228 meters.The thin and poor layers with the larger unproducing sand body have higher remaining oil saturation,the thin layers have better production effect when both thin and poor layers developing.When the perforated zone KH standard deviation of the thin and poor layers is greater than 20 later,oil production and KH standard deviation have a negative correlation relationship,and the results show that untabulated reservoirs independent development is beneficial to the improve the producing degree through the untabulated reservoirs independent development research.By taking measures,this block has the potential of water control,and it played a better role to improve the thin and poor pay zones development effect.According to the effect of the implemented measures,the parameter bound is given:the reperforating layers' water cut is less than 85%;the water plugging layers' water cut is more than 97%;the Fracturing layers' water cut is less than 85%;the best number of subzone in the subdivision reservoir should be controlled within 7,and the sandstone thickness should be controlled within 5 meters.