The Shunan Region Maliuchang Jialingjiang Formation Reservoir Logging Evaluation Methods Research

Nowadays, the log evaluation for carbonate rock reservoir is still one of the worldwide difficult problems, which it appears to be the followings aspects: it can not identify accurately the reservoir, can not ascertain if the reservoir is available or not, and as well as the acknowledgement for the fluid property often tend to be mistakes. Meanwhile, the evaluation for carbonate fractured reservoir will be different from the sandstone due to its special void space structure which it has low porosity, nonisotropy and heterogeneity. In this paper, the research area lies in the Maliuchang area of Southern Sichuan province.In this area, its local geology tends to be the following problems, they are-firstly, the lithology is complicated and their vertical distributions appear to the multi-layers; secondly, the reservoir property is not obvious; thirdly, there are big different between the computation results for reservoir parameters of logging and core analysis; lastly, the logging response of gas and water layer are not obvious.The Jialing River formation is commonly divided into 4 sub-facies, among which the micro-facies such as tidal edge strands are the beneficial sedimentary facices for the Jialing River formation reservoir.Furthermore, the rock mineral for the jailing river formation of maliuchang structure are very complicated, which compose of the calcites, limestones, hydrosialites, anhydrites, pyrites, asphalts and so on. Among them, the main clay mineral is illite and the clay distribute in the intercrystal pores.Based on this, the application of overlay technique and crossplot technique is used to build its identification mode of lithology and reservoir logging of this area.Applied the natural gamma curves without containing uranium to calculate shale contents, and computation mode for permeability is K=0.00157 xΦ^2.095, the formation water resistivity(Rw) is treated as around 0.03, cementation exponent m and saturation exponent n are figure out from the experiment for lithologic and electrical property, and then the value of m is 1.67, and n is 1.95.The water formation and gas reservoir are not the same pressure system, and the local high area within the trap scope product waters and appear to be the property of local water-sailing.The research result demonstrated that the valid identification method for the fluid property of the 4^th member of Jialing River formation is the CNL-Rt crossplot technique, while for the fluid property of second member of jailing river formation is AC-CNL crossplot technique.