Abstract：The propagation velocity of seismic wave is dependent on the property of formations，such as formation component，elasticity，density，depth，geologic age，porosity and tectonic activity. The distribution of interval velocity is rich in the information of the formations through which the seismic wave transmits，and can reflect the mechanic property of the formations. According to the interval velocity of the well，the adjacent structure of maximum correlativity is determined by correlation analysis. The interval velocity error compensation function is acquired by Fourier trend surface analysis according to the logged data of the wells in the adjacent structure. Based on the result of borehole stability for the adjacent structure，the prediction models of borehole stability before drilling are established according to trend surface analysis theory，then the safe mud weight range for TalimuYN4 well is determined accordingly before drilling. The field application testifies that the model is feasible.
