Research and Application of Water Flooding Timing and Method for Blocky Bottom Water Fractured Buried Hill Reservoir

Abstract

Oilfield A is a fractured buried hill reservoir in Bohai bay of China. In order to solve the difficult problem of water flooding timing and method in oilfield. Considering the characteristics of the buried hill fractures with stress sensitivity and strong heterogeneity, the ECLIPSE software was used in the research, and a three-dimensional injection-production numerical model for horizontal wells in buried hill reservoirs is established. According to the main research factors in water flooding, a series of water flooding schemes are designed, and the optimization of water flooding timing, oil recovery rate and water flooding mode in buried hill reservoirs were carried out. The results show that the optimum pressure level of fractured reservoir is about 70% of the original reservoir pressure. The optimal water flooding method is the conventional water flooding in the initial stage, when the water cut reaches 80%, it is converted into periodic water flooding. The oil recovery is the highest when the water injection period is 4 months. Field tests show that conventional water flooding is carried out in the initial stage of the oilfield A when the pressure is reduced to 70% of the original. Periodic water flooding is carried out when water cut is 80%. Good development results had been achieved in the 10 years since oilfield A was put into production. The average productivity of single well reached 300 m 3 /d in the initial stage, at present, the water cut is 60%, and the recovery degree is 18.5%, which is better than that of similar oilfields. This technology improves the water flooding effect of blocky bottom water fractured dual media reservoirs in metamorphic buried hills, and provides a reference for the development of similar reservoirs.

Prediction Technology of a Reservoir Development Model While Drilling Based on Machine Learning and Its Application

“…Currently, the exploration and development of buried mountain oil and gas fields have emerged as a crucial area for augmenting offshore oil and gas storage and production [1,2]. Diverging from conventional reservoirs, burial hill reservoirs exhibit high heterogeneity with complex and diverse spatial characteristics, posing significant challenges in their evaluation and development.…”

“…Furthermore, numerous scholars have conducted a comprehensive evaluation of the buried hill development model using geological data such as core samples, thin sections, and well logging data [8,9]. Wang Deying et al extensively employed various experimental methods, including core analysis, X-ray diffraction, scanning electron microscopy, conventional physical properties testing, zircon dating, mineral dissolution simulation, statistical analysis methods to investigate the geological characteristics, genetic mechanisms, and a development model of gneiss weathering crust reservoirs in the Bohai Sea [2,10,11]. Shenwei et al successfully achieved qualitative and quantitative characterization of each phase zone by integrating core samples, rock flakes, conventional logging data, imaging logging data, and array acoustic logging data [12][13][14].…”

3D Physical Simulation of Water Flooding Characteristics of Buried Hill Reservoir with Different Fracture Systems

“…Among them, the metamorphic buried hill reservoir as an important part of the fractured reservoir, plays an important role in the stable production of oil industry [1]- [6]. Compared with conventional sandstone reservoirs, fractured reservoirs have the characteristics of complex geological structure, strong heterogeneity, complex oil and water seepage law, and difficult to control the rising rate of water cut after water breakthrough in oil wells, which make the development of this kind of reservoirs have great difficulties [7]- [12].…”