Isochronal horizons can be obtained through recognizing types of seismic unconformity boundary, the features of seismic facies and the relations of sandbody overlapping.

• 根据地震不整一边界类型、地震相特征、砂体叠置关系变化可以确定小层等时界面，并且等时界面可以从波峰等时渐变到波谷；