Research On Indication Significance Of Production Dynamic Curve Of Fracture Vuggy Carbonate Reservoir

Carbonate reservoirs are one of the most important oil and gas exploration and development fields in the world.With the discovery of large carbonate oil and gas fields in the Tarim Basin and Ordos Basin,the development potential of carbonate reservoirs in China has gradually increased.The development of fracture vuggy carbonate reservoirs is affected by various geological processes such as sedimentation,structure,and karst.There is a large difference between the storage space and sandstone reservoirs.The internal laws of the reservoir reflected are also difficult to identify by conventional reservoir dynamic methods.However,the production dynamics of carbonate reservoirs are intrinsically related to the reservoir type and bottom water characteristics of the reservoirs,and their production performance is also related to the particularity of carbonate reservoirs in the storage space.Therefore,by studying the indication significance of production curve of fracture vuggy carbonate reservoirs,it is of great significance to deeply analyze the development rules of reservoirs and establish development strategies.Because the dynamic production indicator curve is related to the internal production law of the reservoir,this paper takes the fractured vuggy carbonate reservoir in Tahe Oilfield of Tarim Basin as an example,analyzes the particularity and complexity of carbonate reservoir,and establishes five types of energy indicator curve and three types of water injection indicator curve on the basis of fracture cavity combination theory analysis and material balance principle At the same time,in order to further clarify the internal relationship between the energy indicator curve and water injection indicator curve,and verify the applicability of the energy indicator curve and water injection indicator curve in the development process,according to the correlation principle,the high-pressure physical model experiment method and principle of fracture vuggy carbonate reservoir are established Based on the actual situation of fractured vuggy reservoir,the high-pressure physical simulation experiments of different fracture vuggy combination models are carried out.Then,based on the high-pressure physical simulation test,the established interpretation model of production performance curve indication meaning is modified,and the application effect of the two types of indicator curves is compared and evaluated;and then the indicator curve equation after test correction is used The development characteristics of typical fractured vuggy reservoirs are analyzed,and the corresponding development countermeasures are established.The achievements of this paper are as follows: First,the energy indicating curve can be used to analyze the exploitation potential of fractured vuggy reservoir,and can be used to compare the effects of different fractured vuggy bodies and development strategies.The shape of the energy indicator curve can determine the type of fracturecavity body communicated by the oil well.The slope change reflects the volume change of the fracture-cavity body affected by the production process.The parameters of the indicator curve equation can reflect the recoverable reserves and reservoir volume of the oil well at various stages.Second,the water injection indicator curve can effectively evaluate the water injection development effect and guide the improvement of the water injection development effect.The slope of the water injection indicator curve is a function of the volume of crude oil in the formation,and the size of the injection well reservoir can be estimated;whether the water injection indicator curve has an inflection point can be used to determine whether there are fractures and caves in the far end that are connected to the oil well;Third,the highpressure physical model experiment results show that: the strength of the bottom water and whether it is prone to water channeling have a great influence on the development effect.When the reservoir conditions are not easy to water intrusion or the development is not obvious,the presence of bottom water can provide sufficient energy for the development of the reservoir and significantly improves the development effect.When there is no bottom water,the effect of the cave volume and the production rate on the unfilled caves is not obvious;for the filled caves,with the increase of the production rate,the production level drops significantly,and the single cave reservoir is significantly lower than the double cave reservoir;Fourth,through the high-pressure physical model experiment,the energy indicator curve shows that: the larger the volume of the cave,the higher the initial output of elastic energy mining;the recoverable reserves of caves of different volumes and sizes at the same mining rate are relatively close;The relationship indicates that there is an optimal recovery rate;the water injection indicator curve indicates that the recoverable reserves of water injection development under the double-hole model are higher;the larger water injection rate has a significant effect on pressure recovery,but the oil increase is not obvious;reasonable and stable water injection speed can effectively improve the effect of water injection development;Fifth,by analyzing the production process of a typical reservoir,the energy change stage of the oil well can be effectively identified according to the slope change of the energy indicator curve,and then the production countermeasures can be adjusted in time;at the same time,appropriate water injection development parameters can be selected according to the water injection indicator curve to guide the adjustment of the water injection policy.