东海西湖凹陷平湖组沉积环境演化

东海西湖凹陷ＴＷＴ井位于盆地南部，ＰＨＡ井位于盆地西部斜坡，是目前西湖凹陷揭露平湖组最多的两口钻井，以ＰＨＡ，ＴＷＴ井平滑组沉积特征及古生物资料为依据，以海平面升降控相原理为指导，通过旋回地层学分析，建立了Ａ，Ｂ，Ｃ，Ｄ四个等时沉积旋回，而而旋回间两井对比受相应的地震波组控制。通过对比，建立了Ｄｔ－Ａｐ的具最大地史跨度的平湖组沉积序列；而Ｂｔ，Ｃｔ与Ｂｐ，Ｃｐ之间的沉积旋回对比，揭示了同沉积期空间

DEPOSITIONAL ENVIRONMENT EVOLUTION OF PINGHU FORMATION IN XIHU DEPRESSION, THE EAST CHINA SEA

TWT well,located in the southern Xihu depression and PHA well in the west slope of Xihu depression have the thickest Pinghu Fm.up to now.Based on sediment characteristics and biologic data of Pinghu Fm.in TWT and PHA,this paper gives a cyclic stratigraphic analysis(guided by facies controlling principle of sea level changes),and establishes four syndepositional cycles marked with A,B,C and D.Interwell comparison of deposit cycles are controlled by seismic data.The author also sets up a depositional sequence which stands for a longer depositional evolution,compares depositional differences of syndepositional cycles between Bt and Ct and between Bp and Cp and goes into details by a series of subcycles.At last,this paper interprets the depositional history of time space evolution of Pinghu Formation and various depositional types that developed in shore zone under regressive background,and puts forward new interpretations of facies of Pinghu Formation in TWT.