Method for identifying the fluid properties of a hydrocarbon reservoir by using gas logging data

Abstract

The invention discloses a method for identifying fluid properties of oil and gas layers by using gas logging data, comprising the following steps: 1. Sampling downhole fluid: obtaining fluid sample data by using exploratory well oil and gas layer testing, sampling and production well commissioning; 2, determining the type of the fluid sample: on the basis of the high-pressure physical property experimental analysis, the fluid reservoir types are divided into condensate gas, volatile oil and light oil according to the parameters such as the gas-oil ratio, the crude oil density, the heavy component content and the like; 3, obtain gas logging identification parameter of a fluid sample: obtaining gas logging identification parameters Bh*10+sz of a hydrocarbon lay by utilizing gas logging dataof a corresponding depth of that fluid sample; Wh, c1 / (c2+c3+c4+c5); 4, construct a gas logging identification plate: c1 / (c2+c3+c4+c5) is selecte as an abscissa, and Bh*10+sz Wh is the ordinate and is plotted on the graph. The method of the invention can quickly identify oil and gas layers without downhole fluid sampling and reduce the exploration and development cost.

Description

technical field [0001] The invention belongs to the field of oil and gas exploration and development, in particular to a method for determining fluid types in oil and gas layers based on gas logging data. Background technique [0002] The fluid properties of oil and gas fields in the western South China Sea are relatively complex, with condensate gas, volatile oil and light oil distributed vertically. Especially when the formation depth is large, the temperature and pressure are high (150°C, 38Mpa), the physical properties of the reservoir are poor, and the fluid signal in the pores is weak in the logging response, resulting in no obvious difference in the neutron density response of oil and gas layers , it is difficult to identify condensate gas layer, volatile oil layer and light oil only by well logging curves. [0003] At present, the identification of oil and gas layer types is mainly determined by gas triangular charts and Pixler charts, but these methods have strong ...

AI Technical Summary

Problems solved by technology

Especially when the formation depth is large, the temperature and pressure are high (150°C, 38Mpa), the physical properties of the reservoir are poor, and the fluid signal in the pores is weak in the logging response, resulting in no obvious difference in the neutron density response of oil and gas layers , it is difficult to identify gas condensate layers, volatile oil layers and light oil layers only by well logging curves

[0003] At present, the identification of oil and gas layer types is mainly determined by gas triangular charts and Pixler charts, but these methods have strong regional characteristics and limitations, and the discrimination errors are relatively large, so they cannot effectively guide the exploration and development of oil and gas fields. These problems need to improve the traditional technology, so how to invent a method to identify the fluid properties of oil and gas layers using gas logging data has become a problem we need to solve

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