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浙江三门湾为典型半封闭强潮港湾，淤泥质潮滩十分发育，存在沉积地貌相带分异。潮滩发育过程中，冲刷和淤积状态交替，形成涨落潮周期、大小潮周期、年周期、多年周期和风暴的“潮滩循环”，与动力环境因素的周期变化相关；台风引起剧烈滩槽交换，是其重要的非潮汐因素。由于毗邻潮汐汊道，湾内宽广蓄潮区导致强劲落潮优势流，自然状态下潮滩及潮下带淤积缓慢．据２１０Ｐｂ和１３７Ｃｓ分析，近百年来长期平均沉积速率为０．５６～０．８１ｃｍ／ａ。但自６０年代以来，湾内大量围涂堵港，导致潮下带浅滩与深槽淤积加快。
Sanmen Bay, Zhejiang Province is a typical semi-closed strong tidal harbor. Mud tidal flat is well developed and there are differentiation of sedimentary facies facies belt. During the development of the tidal flat, the alternating erosion and siltation states formed the “tidal flat cycle” of the ebb tide, the tidal cycle, the annual cycle, the multi-year cycle and the storm, which were related to the periodic changes of the dynamic environmental factors. The typhoon caused violent tidal flat Exchange is its important non-tidal factor. Due to the adjacent tidal channel, the broad tidal flat in the Bay leads to a strong ebb flow, and the natural deposition of tidal flat and subtidal zone is slow. According to the analyzes of 210Pb and 137Cs, the long-term average deposition rate in the past 100 years was 0.56-0.81 cm / a. However, since the 1960s, a large number of ports have been encircled and blocked in the bay, resulting in a faster deposition of silt and deep grooves in the subtidal zone.