Method of Fluid Identification Based on Crossplot and Total Probability Formula
Guan Ye-qin · Journal of Oil and Gas Technology · 2013
It was usually to take the result of one or few number of crossplots as the final conclusion,however,there possibly existed some other results which were not consistent with them.Therefore,according to the technique of crossplot,the total probability formula was first used for qualitative identification of fluids.The corresponding probability to each fluid property was calculated by the unit of crossplot,and the biggest one was taken as final judging result.In order to get a accurate result,by making full use of well logging and gas logging data during the process of crossplot optimization,the reliability for sources of data and the identification probability in each crossplot was considered simultaneously.The method was applied to fluid identification of complex reservoirs in the western South China Sea,and the coincidence rate reached 90.3%.It indicates that it has the ability of quick and correct decision for formation evaluation and supporting analysis while drilling in exploration and development of oil and gas.