Study on the influence of injection/production type and well pattern and spacing on producing degree of thin and poor layers

• Main Authors: Shuang Liang, Yikun Liu, Ning Zhang, Bo Zeng
• Format: Article
• Language: English
• Published: SpringerOpen 2017-08-01
• Series: Journal of Petroleum Exploration and Production Technology
• Subjects: The thin and poor layers; Injection/production types; Well pattern and spacing
• Online Access: http://link.springer.com/article/10.1007/s13202-017-0379-2
• ISSN: 2190-0558; 2190-0566

Abstract Daqing Oilfield has already entered the period of high water-cut oil production, and currently the target within the oilfield is thin and poor reservoir layers, whose thickness is less than 0.5 m, and it has very low permeability. These layers also have complicated pore structure and poor developmental benefits because of the low permeability, yet several million tons of remaining reserves exist in these low-permeability, poor and thin layers. This paper analyzed the influence of several factors on the degree of production from these thin and poor layers, specifically focusing on the injection/production type and well pattern and spacing, in order to provide guidance for development of thin and poor reservoir. Two producing models were used to analyze the influence of injection and production type on the production degree of these thin and poor layers: water injection into thick layers, and producing from the thin layers, and vice versa. Also, the effects of well spacing and pattern under different pressures were analyzed by calculating the effective producing coefficient and areal sweep efficiency based on the flow tube model and oilfield examples. The results show that the best way to develop a thin and poor reservoir is thin injection and thick production type and that a reasonable well spacing range should be within 200 m. Beyond this 200 m spacing, it is difficult to increase production, even if the reservoir pressure is significantly increased. Graphical Abstract