Pre-drilling and post-drilling analysis method for key geologic risk factors of drilling target

Abstract

The invention discloses a pre-drilling and post-drilling analysis method for key geologic risk factors of a drilling target. The method comprises the steps of predicting pre-drilling risk factors, determining key pre-drilling risk factors, and performing statistics on the occurrence frequency of the key pre-drilling risk factors; obtaining post-drilling failure factors, determining key post-drilling failure factors, and performing statistics on the occurrence frequency of the key post-drilling failure factors; determining pre-drilling and post-drilling consistency risk factors according to the key pre-drilling risk factors and the key post-drilling failure factors, and performing statistics to obtain the occurrence frequency of the consistency risk factors; and based on the occurrence frequencies of the key pre-drilling risk factors, the key post-drilling failure factors and the consistency risk factors, obtaining a pre-drilling prediction coincidence rate and a post-drilling actual coincidence rate to assess the key geologic risk factors. According to the method, the problem that the key geologic risk factors of the drilling target can be qualitatively analyzed only in the prior art is solved, so that the evaluation level can be improved and the exploration risk can be lowered.

Description

technical field [0001] The invention relates to the technical field of oil and gas exploration, in particular to a pre-drilling and post-drilling analysis method for key geological risk factors of drilling targets. Background technique [0002] Drilling targets are usually the basic geological unit for drilling tasks in the process of oil and natural gas pre-exploration. The post-drilling evaluation of key geological risk factors is aimed at the pre-drilling geological risk evaluation. Compare with the geological risk factors predicted during the pre-drilling decision-making, find out the differences and changes, analyze the reasons for the differences, and summarize the experience and lessons, further improve the geological risk analysis model and exploration technology, and guide the next geological risk analysis work . [0003] In the prior art, the analysis of the target post-drilling geological risk is basically a simple qualitative analysis. According to the post-dri...

AI Technical Summary

Problems solved by technology

According to the post-drilling data, the failure factors that lead to the failure to obtain industrial oil and flow are pointed out and the proportion of each failure is counted. There is a lack of pre-drilling prediction and post-drilling quantitative results for the key geological risk factors that cause the target drilling to fail to obtain industrial oil and flow. Comparative analysis is not conducive to improving the level of target evaluation, and cannot effectively guide the next step of exploration to meet the needs of production

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