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Statics correction is one of the most important steps in onshore seismic data processing and is generally calculated with thickness and velocity parameters of a near-surface weathering layer. The methods that invert the near surface structures using the first break-time of seismic data include refraction and tomographic methods. The advantage of the refraction method is that it can obtain a relative accurate delay time, but it relies on other near-surface investigations to obtain the velocity of the weathering layer. The advantage of using the tomography method is that it is capable of obtaining the weathering layer velocity, although it still relies on the other near-surface investigations to determine the thickness of the weathering layer. In this paper, the advantages of both are combined, and the relation between the refraction delay-time and the tomography velocity model is established using the equivalence of the near-surface vertical travel times. Consequently, the thickness and the average velocity of the weathering layer can be extracted. This method works out the statics only with the first break time of seismic data without the aid of other near-surface investigation techniques such as up-hole surveys.