Method and system for evaluating elastic recovery ratio

The invention discloses a method and a system for evaluating an elastic recovery ratio, the method and the system are suitable for a high-saturation-pressure-difference fault control fracture-cavity type oil reservoir, and the method comprises the following steps: collecting geology and production materials about a well to be evaluated; the method comprises the following steps: calculating an accumulated oil production ratio index and a production pressure drop ratio index in real time according to geology and production data, and fitting a preset comprehensive relation equation based on the accumulated oil production ratio index and the production pressure drop ratio index so as to obtain a productivity index according to a fitting coefficient, constructing a comprehensive relation equation containing a cumulative oil production ratio index, a yield pressure drop ratio index and a productivity index, wherein the productivity index is a ratio of fitting coefficients; and determining the ending time of the pur