Research and application of large-scale fracturing imitating horizontal well technology in vertical well

Abstract

Hailaer Basin is rich in geological reserves, but the proportion of undeveloped reserves is high, accounting for 30% of the proved reserves. In order to improve the production degree of reserves and single well production, and realize the purpose of high and stable production of the oilfield. Taking the ultra-low permeability reservoir of oilfield B in Hailaer Basin as an example, this paper puts forward the large-scale fracturing of vertical wells and water injection development technology of imitating horizontal wells. By forming directional ultra long fracturing fractures in the oil layer, this technology can effectively increase the reservoir conductivity, increase the oil well drainage area and water well control area, reduce the well pattern density and improve the production of single well. The research shows that the undeveloped reserves in Hailaer oilfield have the characteristics of low thickness, low permeability and low reservoir quality index. There are 55 large-scale mold fracturing wells in Hailaer oilfield, with an initial oil increase of 2.2 times. The sand amount of large-scale fracturing is 2.5 times that of ordinary fracturing, and the fluid amount and sand intensity are 4.5 times that of conventional fracturing. The vertical well large-scale fracturing imitating horizontal well technology is adopted in Oilfield B. The designed vertical well fracturing fracture is 600m long and 120m wide, and the production effect is good after fracturing. The research results are of great significance to the high and stable production of undeveloped reserves block in Hailaer oilfield and other similar oilfields.

Keywords

• ultra-low permeable reservoir
• starting pressure gradient
• large-scale fracturing
• imitation horizontal well