Identification Methods Study On Fluid Property Of Complex Reservoirs

Because of geological conditions and complex relationshio of oil pools, fluid identification and evaluation of complex reserviors are very difficult. However, oil and gas reserves of complex reservoirs take a significant porortation of discovered reserves. With the exploration technology of oil and gas progress, people pay attention to technology advance of fluid type recognized of complex reservoirs.This paper takes low porosity, low permeability reservoir on deep glutinite and low resistivity reservoir on some oilfield as the main research region. Taking the record of rock core, data of physical property and testing for oil, as well as data of well logging and the geologic control information as the foundation, more than 30 wells mainly aimed in the research area are studied on some methods of fluid property identification. There are three kinds of methods including the conventional oil well logging information fluid recognition methods, the nuclear magnetic logging fluid recognition methods separately, as well as the integrated recognition fluid method using oil well logging and the geological log information. These three methods contain 8 kinds of methods of fluid property identification. In view of the formation geology characteristics of different research area, we contrastively analyse the superiority, serviceability and applicability of each kind of method.In the methods of conventional oil well logging fluid property identification, it proposes electronic resistivity-porosity cross plot version law as well as the total differential recognition fluid method to the Archie's formula, which are established in view of the granulated substance conglomerate reservoir. The method of correlation between constructive electronic resistivity and actual electronic resistivity is proposed aimed at low resistivity reservoir. Moreover, in the practical application, this kind of method obtains the expectation effect on glutinite reservoir.In the method of nuclear magnetic logging fluid recognition which mainly uses the parameter extracted by nuclear magnetic spectrum recognize different fluid. First in view of the reservoir of low porosity and low permeability, I have studied a kind of sole parameter recognition fluid method by the computation geometry mean value making use of T2 nuclear magnetic spectrum. Next I have studied the method to recognize fluid property by the intersection between T2 geometry mean value and the right boundary of nuclear magnetism. At the same time I also have manufactured the cross plot version. The two fluid identification's method of nuclear magnetic logging will have better effect in the conventional reservoir. Hereafter aimed at some wells which have array sonic information, I have developed a new method to implement fluid property identification, which makes use of the identify divisor constructed by array sonic wave. This method which gains particular effect in the glutinite reservoir and low resistivity reservoir has certain application promotion significance.Gas logging which is a kind of direct-viewing information has been introduced in the synthesis method of fluid property identification. The method takes conventional fluid recognition method's achievement of above and data of gas logging as the input parameter. It could carry on the independent fluid property identification's forecast by making use of the method of BP network forecast, which has become a set of synthesis technical measure to implement fluid property identification. Various fluids recognition methods have made certain accomplishment in the suitable wellfiled. Among these methods, perfect differentialed Archie formula in glutinite reservoir, structured resistivity contrasting to deep resistivity reservoir and comprehensive measures are most effective,which have achieved to enhance accuracy degree of fluid indentification.The research conten of this paper are used in actual well site, which prove the serviceability of these methods. These methods have provided the standard of oil and gas interpretation, which has achieved the anticipated target.