Elevation and subsidence of base level,accompanying change of accommodation space,leading to denuda- tion,transportation,passing by,sedimentation or undercompensation of sediments in various facies tracts,would re- sult in cyclic sequences.

• 基准面升降伴随着可容纳空间的变化,导致沉积物在不同相域发生剥蚀、搬运、过路、沉积或欠补偿作用而形成旋回性沉积地层。