Conventional Logging Evaluation Integrated Study On Fluid Property Of The Carbonate

Compared with clastic rock oil and rock exploration, exploration in the carbonate rock is more difficult and challenging. That is largely because the porosity and permeability heterpgeneity features of the space reservoir of carbonate reservoir rocks are very obvious. This is mainly caused by the following factors:(1) Complex types of native pore. Carbonate sediment are largely for biological reasons. There are large numbers of native pores inside and between biological particles as well as among reef body biological skeletons. Development degree, of different biological types in different historical and biological, is of great difference, which is much complex than the clastic difference.(2) Complex type of secondary porosity. Due to the strong chemical activity of carbonate minerals, and the brittle character of carbonate rocks they will form a large number of complex secondary porosity after the carbonate rocks are generally deposition, diagenetic stage, epigenetic or supergene of the transformation process. And they distribute with a lot of randomness.(3) Different types of carbonate reservoir made from complex primary porosity and secondary porosity combination.Difficulties to identify Carbonate reservoir fluid type:carbonate reservoir porosity, reservoir space structural complexity and heterogeneity of different reservoir space fluid in a different state. Different genetic types of reservoir characteristics are quite different karst development reservoir drilled both oil and gas layer or water layer has a certain air of measured display. At present, the carbonate reservoir fluid properties to evaluate the main basis for reservoir resistivity. According to the study, the different pore structure of rock formation factor F, that is the value of m in Archie’s equation. For example, the general solution and pass the reservoir m value is approximately equal to2; local layer cracks, the value of m is less than2; if there is a cave, m values greater than2. Therefore, the different pore structure of oil and gas reservoir, the differences in resistivity will have a significant, if only depending on the size of the resistivity regardless of the pore structure differences appears incorrect interpretation of results.Therefore, the comprehensive utilization of electrical measuring gas log cross plots under different reservoir types to identify the fluid properties.By conventional logging intersection of plates and gas logging data to the stratum containing the fluid nature of the discrimination results of the various fluid nature of the identification method are its adaptation side, but also has some limitations.Conventional logging rendezvous Plate Effect of Method Used by the third chapter, the following understanding(1) Saturated double degree difference between the deep resistivity or water saturation have a good ability to distinguish between gas and water layer.(2) Deep and shallow resistivity (Rt/Rxo) and deep resistivity intersection of plates and deep resistivity and porosity crossplot plates, we can clearly distinguish the hydrocarbon layer and water layer, with good results;(3) Neutron and compressional wave slowness, density intersection of plates, four porosity difference and effective porosity crossplot can not distinguish between the reservoir and the water layer in the carbonate reservoir within the study area does not have the feasibility of application(4) Space modulus difference between the ratio of effective porosity intersection plate method in the study area effect is poor;(5) Longitudinal wave velocity and porosity crossplot plates can not be clearly hydrocarbon layer and water layer, the application of in the work area to be further validation.Reservoir hydrocarbons and component values in the gas logging map there will be the exception, according to the total hydrocarbon content of the gas measured curve, the peak shape characteristics and composition identify the reservoir and gas reservoir, combined gaslogging technology inwellhead stratigraphic hydrocarbon continuous monitoring, logging data with continuous detection, real-time characteristics of the fractured layer, the light oil layer, oil and gas condensate layer fluid nature of the identification with other technologies that are not continuous, sensitivity advantage. Through the analysis of the fourth chapter of this thesis, the following understanding:(1) PIXLER method is simple in calculation, to evaluate the advantages of fast, according to different types of fluids with different characteristics from the C1/C2, C1/C3ratio, draw the cross plot can be a good area to separate the oil layer and gas reservoir.(2) The biggest feature of the light hydrocarbon ratio method is the density of the crude oil, gas humidity and gradual process to make clear, intuitive description, and the distinction between oil and residual oil, light oil, condensate and gas oil ratio is also veryobvious. Establishment of WH and BH crossplot more pronounced regional separation of gas and oil reservoir, and also display pure gas reservoir of gas oil(3) According to the M position determined by the hydrocarbon triangle and triangle positive and negative Q value in the study area, carbonate reservoir to better distinguish between oil, gas reservoir.(4) Hydrocarbon gas measurements the absolute value of the total hydrocarbon, the relative value of high resistivity; the absolute value of the water layer of gas measured total hydrocarbon low resistivity is relatively low value, the establishment of the work area by RT, any two of the cross plot of the TG and Cl, you can also achieve a more good recognition results.In practical applications, the fluid nature of the target layer recognition, it is recommended that the testing data, choose a variety of comprehensive fluid nature of discrimination, in order to achieve the most accurate and reliable identification.