| On the basis of a profound understanding of the research on reservoir geological characteristics, this paper takes the modern reservoir engineering theory as a guide and comprehensively uses the reservoir physics, seepage mechanics to make a research of the characteristics of the productions、the pressure、the water breakthrough and the arise of productions、the development effects of water drive and the rules of declines of productions. The reasonable technologies and rules of the area were made. They gave a guidance to the rightful and high efficient development in the future. The mainly acquired outcomes are in the below:(1)The areas in which the single well production is high are mainly located in the center and south of the region of interest. The west is second to the above and the worst is in the northeast. The analysis of factors to influence the productivity:the better the reservoir properties, production capacity is relatively higher, but there are more factors that influence on the productivity of the study area including the reservoir heterogeneity, structure, implementation measures of reformation and the changes of the injection volume.(2)The types of oil well can be divided into the following four categories in the producing the desired results:Class I is the effect obvious type,accounting for 21.7%. Class II is the stable type,accounting for the 50.0%. Class III is the water breakthrough type,acounting for the 13.1%. Class IV is the type whose productions go up with the measures,accounting for the 15.2%.The water breakthrough type of the study area can be divided into the following two categories:Class I is the water breakthrough in the pore apace,accounting for the 48%. Class II is the water breakthrough in the microwaves,accounting for the 52%. The water breakthrough reasons of study area can be divided into:①there are many micro cracks in the area; ② the injection intensity leads to the rapid rise of the water content.(3)The producing degree of reserves of the Chang81 of the Zhen 287 area is 52.2%,the water storage rate is 92.01%,the water flooding index is 3.06,the volumetric sweep efficiency is 8.79%,the water flooding recovery is 17.97%.Comprehensively comparing them,the water flooding effect is poor in the study area.(4) Pressure system:with the use of the reservoir engineering demonstration and numerical simulation, the reasonable flow pressure of Chang 81 reservoir in the Zhen 287 area is 4.77～8.00MPa, the rational formation pressure maintenance level is 16～22MPa, reasonable production difference pressure is 11.0MPa, the pressure for fracture formation is about 46.42MPa, the maximum pressure of wellhead is about 22.41 MPa.(5) The injection production parameters:with the use of field practice、reservoir engineering and numerical simulation, the reasonable injection intensity of Chang 81 reservoir in the Zhen 287 area is about 0.17 t/m.d; the reasonable intensity of production is about 1.7-2.0m3/m.d; injection production ratio should be controlled at 2.5～3.0,due to the development of micro cracks.(6) At present, the well pattern in the study area is rhombus inverted 9 spot well pattern. By using reservoir engineering method and numerical simulation, the reasonable well pattern density is 12 well/km2,the well pattern density present is 7.38 well/km2.It can be obtained that more wells are need to improve the well network form and tap the potential of remaining oil for enhancing the recovery rate of the study area. |
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