We have provided in this paper an attempt to study the deformation of oil wellbore using modeling because of its capability to analyze the different hypotheses which give us a vision of what is happening or could happen . We have built a model of the phenomenon being studied are expressed in a horizontal section of the oil well on the geological layer , after loading forces and stresses, we analyzed the results ( deformations ) for the sandstone ( elastic rock ) and clay (plastic rock ), where it is shown- by making a hypothesis fit with abnormalities in the state of the stresses in the oil fields - that the anomalies in the state of stresses of principles geological stresses plays an important role in the deformation of oil wellbore.