One kind of seam fracturing fluid system

The invention relates to a method for pressing crack a coal bed pressing crack liquid, which sequentially comprises the following steps of: (1) selecting high-viscosity pressing crack liquid types used for the coal bed hydraulic cracking; (2) carrying out glue breaking experiments on pressing crack liquid adopted by chlorine dioxide indoors under the condition of the coal bed temperature and determining the minimum concentration of the chlorine dioxide; (3) determining the total quality of the chlorine dioxide according to the quantity of the pressing crack liquid and the concentration of the chlorine dioxide; (4) carrying out hydraulic pressing crack according to a procedure of prepad liquid, sand containing liquid and replacing liquid, wherein the chlorine dioxide added in the prepad liquid accounts for 70 percent, the chlorine dioxide added in the replacing liquid accounts for 30 percent, and not less than 10m of active water or clean water is pumped and injected among the prepad liquid, the replacing liquid and the sand containing liquid for being used as isolation liquid; (5) starting to do pressing crack liquid backflow after the waiting for 2 to 4 hours from the completion of the hydraulic pressing crack; and (6) checking effects with the main indexes including the pressing crack liquid backflow quantity, the viscosity and the damage degree of the pressing crack liquid on the coal bed. The coal bed pressing crack liquid system has the advantages that the high-viscosity pressing crack liquid can realize fast glue breaking backflow at the coal bed temperature, and the damage to the coal storage layer is reduced.