关键词: 低渗透储层, 沉积作用, 成岩作用, 构造作用, 巴什基奇克组, 塔里木盆地

Abstract:

Horizontal wells have advantages to vertical wells in developing low quality petroleum resource. However, the conventional production rate equations of horizontal wells seldom take into account the skin factor of wells, with which production rates of horizontal wells cannot be well predicted. Based on the equivalent flow resistance theory, a new production rate equation of horizontal wells was derived in this paper with the skin factor. Two skin factors are introduced into the new equation, which are formation damage skin factor and formation improvement skin factor. The formation damage skin factor is resulted from mud intrusion in drilling and completion of wells, while the formation improvement skin factor is resulted from stimulations of wells such as acidizing and fracturing. The two factors have different effects on production rates of horizontal wells. The formation damage skin factor affects production rate of horizontal wells to a quite small extent, however the formation improvement skin factor to a quite great extent. So, the formation protection in drilling and completion of horizontal wells are not necessary, while the stimulations are effective methods to enhance the productivity of horizontal wells.

Key words: low permeability reservoir, sedimentation, diagenesis, tectonism, Bashijiqike Formation, Tarim Basin