The shallow and thin layer heavy oil reservoir of Pai-601 block in Xinjiang adopts HDNS (horizontal well+ dissolver + nitrogen gas+ steam injection) to develop the heavy oil reservoir. It has made a significant effect, solving production problems of the block, such as: low natural energy, less thermal loss, and less oil cycle production. In order to improve the next process scheme, we have conducted a thorough study of its mechanism. The best HDNS’s parameters of Pai-601 block were chosen as follows: steam injection is 9.5~10.5 m3/m, nitrogen gas injection is 140~160 Nm3/m and thinning agent’s optimum dosage is 0.10 t/m. Key words: Shallow and thin layer; Super heavy oil; The technology HDNS; Mechanism; Scheme optimization
