Evaluation method for residual hydrocarbon content of marine high and over-mature source rocks

Abstract

The invention belongs to the technical field of oil and gas exploration, and aims to solve the problems of poor accuracy and dependence on low-mature samples of the existing methods for evaluating the residual hydrocarbon content of high and over-mature source rocks, and particularly relates to a marine high-over-mature source rock residual hydrocarbon content. The evaluation method includes establishing the evolution profile of hydrocarbon generation potential of high and over-mature source rocks and the evolution profile of hydrogen index of source rocks; Hydrocarbon potential; invert critical conditions for hydrocarbon generation of high and over-mature source rocks; establish a model for residual hydrocarbon generation and expulsion of high and over-mature source rocks; determine hydrocarbon generation, expulsion and residual hydrocarbon rates of high and over-mature source rocks; calculate high and over-mature hydrocarbons Source rock residual hydrocarbon intensity and residual hydrocarbon amount. The evaluation method disclosed in the invention can establish a model that does not depend on low-mature samples and is suitable for evaluating the residual hydrocarbons of high and over-mature source rocks, provides a scientific basis for the evaluation of shale oil and gas resources, and provides a powerful theory for the evaluation of shale oil and gas exploration target selection areas Guidance and technical support.

Description

technical field [0001] The invention belongs to the technical field of oil and gas exploitation, and in particular relates to a method for evaluating the amount of residual hydrocarbons in marine highly over-mature source rocks. Background technique [0002] There are huge shale oil and gas resources in source rock formations, and the residual amount determines the potential of shale oil and gas resources. The evaluation of residual amount is of great significance for the evaluation of shale oil and gas resources and the selection of favorable exploration targets. How to establish an evaluation model for the residual amount of highly over-mature marine source rocks and calculate the amount of residual hydrocarbons has been an unresolved problem in the geochemical community for a long time. The immature and low-maturity source rocks cannot reconstruct the complete evolution process of hydrocarbon generation, retention and expulsion of source rocks. [0003] In the process of...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the above-mentioned problems in the prior art, that is, in order to solve the problems of poor accuracy and dependence on immature and low-mature samples in the existing methods for evaluating residual hydrocarbons of highly over-mature source rocks, the present invention provides a marine high-over-mature hydrocarbon A method for evaluating the amount of residual hydrocarbons in source rocks, the method comprising the following steps: step S100, establishing a hydrocarbon generation potential evolution profile of highly over-mature source rocks and a hydrogen index evolution profile of source rocks; step S200, determining The critical condition of hydrocarbons is to invert the original hydrocarbon generation potential of source rocks; step S300 is to invert the critical conditions for hydrocarbon generation of over-mature source rocks; step S400 is to establish a residual hydrocarbon model for over-mature source rocks; Hydrocarbon generation rate, hydrocarbon expulsion rate and residual hydrocarbon rate of mature source rocks; step S600, calculating residual hydrocarbon strength and residual hydrocarbon amount of over-mature source rocks

Images