Prediction Method For Biantai Buried Hill Reservoir Fractures

The lack of future substitute reserves for Liaohe Oilfield has pushed the search for buried hill reservoir potentials to the forefront,and this is accompanied by the global advance of the technology on recognition and development of fractured metamorphic rocks.Biantai buried hill,as an important target,is composed of Anshan Group metamorphic rocks, its fractures being both traps and flow pathways for hydrocarbons.The accurate definition of the fractures is key to the successful exploitation of the area.At the moment,there are varieties of approaches around the world to investigate the fractures,which provide favorable provisions for recognizing and mastering the nature of the fractures and to further improve the development benefit of the fractured reservoirs. However,these approaches have certain application conditions. For different types of fractured reservoir,the theoretical models,technical solutions and calculation parameters are differentiated. The paper mainly studies the prediction of stress and the distribution of structural fractures by way of finite element. Upon the geological features of Biantai buried hill reservoir,theoretical model for prediction of stress and structural fractures by finite element numerical simulation is established and proper calculation methods are found. After detailed study,reasonable calculation parameters are chosen. With the above mentioned foundation.Actual calculating simulation is conducted for Biantai buried hill reservoir. According to the study result of stress and fracture,analysis of the oilfield development scenarios is done and optimization principles and methods are given.The simulation involved great number of data with complicated backgrounds. The design and analysis are difficult to make.However,compared with the actual situation,it is proved that the study result of this paper is in accordance with the oilfield performance and the theoretical methods are accurate and feasible. The work that has done is of great value to the study of stress study of fractured reservoir and the development of this kind of reservoirs.Several breakthroughs were achieved during the research:1.Elastic mechanics and finite element methods are employed to form a sound and ractical systematic framework to predict structural stress and fractures.2.3D finite element numerical simulation can present the actual distribution of formations and structures.After some processing for the thin beds and faults,without further constraints, the calculation can produce the trustworthy spatial distribution of stress and fractures.3.The research results achieved on stress and structural fractures has been employed as guidelines for the well planning for Biantai Buried hill reservoirs,and having been proved effective in the field practices.