Shale loss gas calculation method and system

Abstract

The invention discloses a shale loss gas calculation method and system. The method comprises the steps that based on coring and well drilling and completion data, obtaining the core pore structure, the gas reservoir pressure, the core drill lifting time, the desorbed core quality, the shale gas accumulated desorbed gas amount and the accumulated desorption time of a shale gas reservoir; acquiringa shale gas desorption rate based on the shale gas accumulated desorption gas amount and the accumulated desorption time; and based on the gas reservoir pressure, the core pore structure and the shalegas desorption rate, obtaining the content of the shale lost gas under the ground condition. The method has the advantages that the shale lost gas content can be more accurately calculated, and the lost gas content is calculated based on the gas reservoir pressure condition, so that the reliability and accuracy of obtaining the lost gas content are improved, and reliable guarantee is provided forshale gas reservoir reserve calculation and productivity prediction and evaluation.

Description

technical field [0001] The invention relates to the technical field of shale gas exploration and development, and more specifically, to a method and system for calculating shale gas loss. Background technique [0002] Shale gas content is an important parameter for calculating the original gas volume of shale, evaluating regional resource reserves, and selecting favorable mining areas. The measurement and evaluation of this parameter is directly related to the success of mining, and has great significance for the evaluation and development of shale gas resources in my country. significance. Therefore, the determination of shale gas content is an important task in the process of shale gas exploration and evaluation, and it is an important parameter for calculating shale gas reserves and formulating development plans. [0003] According to exploration and development experience, high on-site desorbed gas content generally indicates higher total gas content. The desorbed gas co...

AI Technical Summary

Problems solved by technology

Different mathematical regression methods can calculate different lost gas content, but this regression calculation does not take into account geological conditions such as gas reservoir pressure, reservoir type and characteristics, especially in ultra-high pressure shale gas reservoirs in the basin. At the moment of the gas layer, due to the destruction of the pressure balance, a large amount of natural gas is lost in an instant. This part of the lost gas is difficult to estimate. The later recovery calculation is mainly based on the desorption law and the method of mathematical fitting is not suitable for the calculation of this part of the lost gas.

Therefore, the gas loss calculated by this method cannot be more objective and close to the reality of the actual gas loss in shale.

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