A Case of Multi-Stage Fracturing Horizontal Well Used in BZ Oilfield in Bohai Bay Low-Permeability Oilfield Development

摘要

BZ oilfield in Bohai Bay of China was a typical offshore low permeability oilfield, which was restricted by many factors such as environment and economy. In this paper, the development characteristics of BZ oilfield were summarized in depth, and the new development mode of offshore low-permeability oilfield was explored from reservoir prediction, well spacing and fracturing technology. Taking BZ oilfield as an example, a set of technical system for the effective development of offshore low permeability oilfield had been formed through research, which mainly includes reservoir prediction and evaluation of offshore middle and deep low permeability oilfield, optimization of horizontal well pattern, multi-stage fracturing design of horizontal well and other technologies. The results show that improving the resolution of seismic data, strengthening the analysis of seismic reflection characteristics and carrying out the comprehensive study of seismic geology were the keys to solve the reservoir prediction of offshore low-permeability oil fields. Multi-stage fracturing horizontal well pattern is the main pattern of offshore low-permeability oilfield development. The parameters of multi-stage fracturing horizontal well together affect the development effect. Selecting the optimal fractured horizontal well pattern can greatly improve the development effect. The successful combination and application of new technology system was the foundation and core of conquering offshore low-permeability oil fields. On the basis of understanding the geological characteristics of oil reservoirs, it is an effective means of developing offshore low-permeability oil fields by selecting reasonable production methods, well types and well patterns. Using efficient perforation and fracturing technology to successfully control fracture parameters and form optimal injection and production well pattern was the key to improve low permeability offshore oil fields.