Liaohe Oilfield,the largest heavy oil production base in China,features in various reservoir types,deep burial,and wide range of crude oil viscosity.For many years,a series of technologies have been developed for different oil products and reservoir types of the oilfield,of which water flooding,foam slug drive,steam stimulation,steam drive,and SAGD are the main technologies.After continuous improvement,they have been further developed and played an important role in the development of heavy oil in the oilfield.