In order to reveal the complex subsidence history in northern Huizhou sag of Pearl River Mouth Basin,Cenozoic subsidence history in northern Huizhou sag was analyzed based on EBM basin modeling system and 30 seismic profiles controlled by well,the temporal-spatial differences of subsidence between syn- and post-rift stages and their main control factors were discussed,macroscopic effects of regional lithosphere mantle on subsidence were studied,and the constraint of local complex tectonic framework,migration and evolution of tectonic on subsidence were explored.The results show that at syn-rift stage,the subsidence rates are large,there are lots of subsidence centers which isolate from each other,and subsidence characteristics and rates vary temporally and spatially in northern Huizhou sag of Pearl River Mouth Basin; from Wenchang to Enping periods at syn-rift stage,subsidence becomes stronger and more homogeneous, subsidence centers decrease and migrate westwards and southwards;the activities of different fault segments together with the low uplift control the development of subsidence centers;the changes of tectonic intensity and direction together with the heterogeneity of basement property are the dynamic background which cause the migration and evolution of subsidence centers and the change of subsidence intensity; at post-rift stage, the subsidence is regional slow and homogeneous,subsidence rates of all structural units are similar, and HZ14 sub-sag is a sustained subsidence center;the observed tectonic subsidence is considerably greater than the theoretical value at post-rift stage,post-rift anomalous subsidence develops,and there is a short-lived rapid subsidence in 1 6.5-18.5 Ma;thermal subsidence is basic driving mechanism at post-rift stage,and post-rift anomalous subsidence caused by dynamic topography and rapid subsidence caused by late tectonic movement event are overlaid.%为了揭示珠江口盆地惠州凹陷北部复杂沉降区的沉降历史，运用井控30条骨架剖面和EBM 盆地模拟系统，分析惠州凹陷北部新生代沉降史，探讨裂陷期与拗陷期沉降作用时空差异及其主控因素，研究了区域性岩石圈地幔对沉降作用的宏观影响，并探索了局域性复杂构造格架及构造的迁移演化对沉降作用的制约.结果表明：珠江口盆地惠州凹陷北部裂陷期强烈的沉降作用表现为沉降速率大、沉降中心多且分散以及时空差异大；从裂陷期的文昌期到恩平期，沉降作用增强且趋于统一，沉降中心减少并发生由东向西和由北向南的双向迁移；断层的分段差异性活动以及低凸起的分割作用控制了沉降中心的发育；构造作用强度、方向的转变以及基底属性差异是控制沉降作用强度变化和沉降中心迁移演化的区域动力学背景；拗陷期沉降作用以区域性缓慢均匀沉降为特征，各构造单元沉降速率相近，其中 HZ14洼是持续发育的沉降中心；拗陷期构造沉降量观测值远大于理论值，发育裂后异常沉降，且16．5~18．5 Ma 期间发生了加速沉降；拗陷期以热沉降为基本驱动机制，叠加了动力地形造成的裂后异常沉降和晚期构造运动事件导致的加速沉降.
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