摘要
The foraminifera fossils are not only an excellent evidence for determining stratigraphical ages, but also sensitive organisms indicating the environment of ocean and transitional area between marine and continental facies, playing an important role in the reconstruction of ancient environments which existed hundreds of millions of years ago. In recent years, studies of oil and gas fields in the world have proved that neritic facies and transitional environment between shallow sea and continental facies were excellent reservoirs for patroleum and gas formation. Therefore studies on
