Method for correcting movable hydrocarbon content of high gas-oil ratio shale oil based on phase behavior and rock pyrolysis

A method for correcting a movable hydrocarbon content of shale oil based on phase behavior and rock pyrolysis, comprising following steps:

• S1, simulating and preparing a fluid under original formation conditions based on formation fluid properties of a target block;
• S2, performing a pressure-volume-temperature (PVT) experiment and a fluid property test on the fluid prepared in the step S1 to obtain a composition of well fluid and a deviation factor;
• S3, establishing a theoretical shale movable hydrocarbon content prediction model to calculate a shale theoretical movable hydrocarbon content and a light hydrocarbon correction factor;
• wherein the theoretical shale movable hydrocarbon content prediction model is as follows:
• S
• KD
• =
• P
• p
• ⁢
• V
• b
• ⁢
• ϕ
• ⁢
• S
• 0
• ⁢
• M
• ×
• 10
• 6
• ZRT
• p
• ⁢
• m
• b
• (
• 1
• )
• where SKD represents the shale theoretical movable hydrocarbon content, in a unit of milligram per gram (mg/g);
• Pp represents a formation pressure, in a unit of megapascal (MPa);
• Vb represents a volume of a core sample, in a unit of cubic meter (m3);
• ϕ represents a porosity of the core sample, in percentage (%);
• S0 represents an oil saturation of the core sample, in percentage (%);
• M represents a relative molecular weight of the fluid as simulated, dimensionless;
• Z represents the deviation factor, dimensionless;
• R represents a molar gas constant 0.008314;
• Tp represents a formation temperature, in a unit of Kelvin (K);
• and mb represents a weight of the core sample, in a unit of gram (g);
• wherein the light hydrocarbon correction factor is calculated as per the following formula:
• K
• =
• S
• KD
• -
• S
• 1
• ⁢
• total
• S
• 1
• ⁢
• total
• (
• 2
• )
• where K represents the light hydrocarbon correction factor, dimensionless;
• SKD represents the shale theoretical movable hydrocarbon content, in the unit of mg/g;
• and S1total=S1-1+S1-2, where S1-1 represents a content of light oil, S1-2 represents a content of light-medium oil, and S1total represents a total light hydrocarbon content;
• S4, determining, based on the light hydrocarbon correction factor obtained in the step S3, a restored light hydrocarbon content of shale oil and a restored original total oil content;
• and
• S5, determining, based on the restored light hydrocarbon content of shale oil and the restored original total oil content, the target block whether as a to-be-exploited region;
• and in response to the target block is determined as the to-be-exploited region, exploiting shale oil from the to-be-exploited region.