A Method for Predicting Technically Recoverable Reserves of Oil and Gas Wells

Abstract

The invention provides an oil and gas well technical recoverable reserves prediction method. The method comprises: collecting daily output and accumulated output data; according to the daily output and accumulated output data, drawing a daily output and material balance time relation curve, the material balance time being ratio of accumulated output and daily output in corresponding time, then, through taking a derivative of the daily output and material balance time relation curve, drawing a feature segment, the feature segment being a segment whose slope is a special value; according to the distribution condition of the feature segment in the daily output and material balance time relation curve, determining a flow filed type, and then according to the flow filed type, establishing a corresponding production decline analysis model; finally, under a set constraint condition, according to the production decline analysis model, predicting technical recoverable reserves. In the method, the production decline analysis model is unified in the same decision rule, and analysis and selection of adaptability of the production decline analysis model are performed through flow field identification, so as to predict technical recoverable reserves. The method can solve technical problems in the prior art that a prediction result is not determined caused by blindly choosing a model, and the method improves prediction precision of the technical recoverable reserves.

Description

technical field [0001] The invention relates to oil and gas exploration prediction technology, in particular to a method for predicting technical recoverable reserves of oil and gas wells applicable to dynamic evaluation of shale gas wells and other types of oil and gas wells. Background technique [0002] Recoverable oil and natural gas reserves refer to the amount of oil (gas) that can be recovered from an oil (gas) well (field) (reservoir) under the current industrial technical conditions. Recoverable reserves are not only related to natural conditions such as oil (gas) reservoir type, reservoir physical properties, fluid properties, driving type, etc., but also to man-made factors such as well layout, injection mode, oil recovery technology, oil (gas) field management level, and economic conditions. factors. Technically recoverable reserves refer to the recoverable reserves that may be recovered based on the current industrial technical conditions, but have not undergon...

AI Technical Summary

Problems solved by technology

The above three models are all empirical or semi-empirical models. Under the current conditions, when applied to field wells, the effect is good and bad, and it is difficult to obtain definite prediction results.

Based on the different models formed by conventional oil and gas wells and shale gas wells and other unconventional oil and gas wells, there is no unified analysis method, and it is difficult to carry out effective model selection. The blindness of model application affects the application effect

Images