Because of the disadvantages of low accuracy

high cost and inconvenience for field application of current fracture monitoring methods

it is necessary to develop a new approach to monitor the parameters of hydraulic fractures in reservoirs.Based on the theory of tri-linear fluid flow in porous media

a novel seepage model was developed for multistage-fractured horizontal wells in reservoirs with micro-fracture.Laplace transform was performed to derive well production rate formulas for different typical flowing periods.The field daily production data were used to analyze the typical characteristics of diffe-rent segments of the production curve and to solve the model for fracture parameters including hydraulic fracture length

hydraulic fracture flow conductivity and permeability of natural fracture in the reservoir.The model was validated with the microseismic monitoring data of 3 horizontal wells in the field.The results show that the relative error of the hydraulic fracture flow conductivity between the prediction result and the real value is 1.9%

and the hydraulic fractures lengths from model calculation are in good agreement with the micro seismic monitoring results.With the advantages of conve-nience

rapid interpretation

high accuracy and good adaptability

this method proposed in the paper is helpful to the evalu-ation and design of horizontal well multistage-fracturing stimulation in reservoirs with well developed micro-fractures.