Reservoir Characterization And Evaluation On Favorable Areas Of Glutenite Reservoir In Moliqing Oilfield, Yitong Basin

In recent years, as the extent of oil and gas exploration continues to mature, the status of subtle reservoir exploration gradually show up, the statistical reserves account for about one-third of global reserves, the rule of the world’s oil and gas exploration shows in the development from the structural traps to the invisible traps, China has also entered the exploration and development stage of hidden reservoir. Glutenite reservoir is an important type of subtle reservoirs. It is widely distributed in China and has great exploration potential, but the forming of glutenite reserve is because of the gravel deposits after slumping and fast deposition, the spatial distribution of reservoir is complex and the heterogeneity is strong, so in terms of difficulty of exploration and development, it is more difficult than the conventional oil and gas reservoirs.In the Iraq Yi45-59 blocks of Moliqing oilfield, aiming at the problems of complex glutenite reservoirs, difficult evaluate, complex oil-water relationship and difficult fluid identification, basing on the previous sequence, structure and understanding of the deposition, we make a study on the characteristics of reservoirs, implement the reservoir insider, ensure the sand body oil-water relationship and set up a three-dimensional geological model to provide a reliable geological basis for forecasting the favorable areas. We have formed a series of methods aiming at the complex glutenite water reservoir evaluation and the oil-water identification. The achieved results and innovation are as the following.(1) The detailed description and characterization of interlayer in the double two reservoirs of y45-y59 block of Moliqing oilfield is to recognize the reservoir spatial distribution.With the characteristics of tight lithology, complicated pore structure and strong heterogeneity of the double two reservoirs of y45-y59 block of Moliqing oilfield, using the method of the combination with reservoirs qualitative and quantitative, the combination with micro and macro, and the fundamental characteristics of reservoir lithology, physical, rock characteristics, micro pore, the detailed analysis of the sensitivity characteristics and the distribution of reservoir heterogeneity and interlayer, which is to propose the main factors causing the reservoir sensitivity by the high content of clay minerals. Though the analysis of the effect in different degree of heterogeneity for residual oil, consider one of the important factors causing residual oil is the serious heterogeneity. The interlayer standard for sedimentary model of the slope apron is established and the distribution of interlayer in the blocks is also studied.(2) The established standard of fluid identification with partition block and lithology in the study area and the certain distribution of the oil-water provide the geological basis for the distribution of reserves evaluation.For the sedimentary system of the slope apron and the characteristics of the reservoir with oil-water distribution of complex and oil-water layer identification, firstly using the basic of lithology and fault sealing to divide block, then under the guidance of logging theory, combined with conventional method of the fluid identification, response characteristics of the respectively optimized fluid logging curves in each block, for the difficult to distinguish fluid in the study area, put forward the method of coordinate rotation and build recognition method and criterion suitable for the fluid in the study area. On the basis of knowing reservoir and delineation containing area, evaluate the distribution of reserves.(3) To establish three-dimensional geological model of repeated reverse fault strata in the study area.For complex structure under the background of reverse fault in Moliqing area, with the base of early sequence, structure, deposition phase and reservoir fine description, using fine 3D geological modeling method established tectonic model of repeated formation reverse faults, using thoughts of facies controlled modeling, establish the sedimentary facies model and phase control attribute model of complex gravel rock reservoir controlled by depositional system of slope apron, provides a reliable basis for the evaluation of reserves distribution.