Method for tracing diagenetic fluid source based on gas composition in fluid inclusion

The invention discloses a method for tracing a diagenetic fluid source based on a gas component in a fluid inclusion, which comprises the following steps: step 100, screening a qualified rock sample for pretreatment to obtain a rock sample with a gas-liquid two-phase fluid inclusion; step 200, placing the rock sample in a vacuum chamber filled with a mass spectrometer for rapid crushing, and carrying out quantitative analysis on released trace gas to obtain a tracing chart; step 300, accurately tracing the source of the diagenetic fluid based on the parameter ratio of the tracing chart; according to the method, the thin sheet and the thick sheet are respectively obtained by adopting a mirror symmetry mode based on the extraction characteristics of the fluid inclusion in the rock sample, and the position of the fluid inclusion in the thick sheet is subjected to mirror positioning based on the observation positioning mark of the thin sheet, so that the fluid inclusion is accurately extracted; trace and even tra