Abstract
At present, the main energy resources used are oil, natural gas, and coal, which are commonly referred to as conventional energy resources. In addition, there are large amounts of so-called unconventional energy resources. Since 2000, the development of technology has advanced and the movement toward the commercialization of unconventional oil and natural gas has increased. Unconventional energy is divided into unconventional oil and unconventional natural gas. Unconventional oil includes tight oil, shale oil, oil shale, and oil sand. Unconventional natural gas includes coalbed methane, tight gas, shale gas, natural gas hydrate, and water-soluble gas. Although the exploration and development of unconventional oil and gas have attracted wide attention, there are still some differences in the understanding of its concept. This paper mainly introduces the classification and geological characteristics of unconventional oil and gas resources.
