分析广海湾海域实测潮位资料，发现在该海域的潮位在低高潮期间存在多个峰值。通过不同分潮组合进行水位重构，并基于其他学者的类似研究和数学解析成果，认为造成这种现象的主要原因是该海域的M4等四分之一日分潮的比重较大，全日分潮、半日分潮和四分之一日分潮共同作用的结果。通过改变潮汐边界、近岸水深、地形等影响因素，构建不同的数值模型，探讨M4分潮大振幅的原因。结果表明，广海湾内M4分潮振幅较大的主要原因是该海域的M4分潮整体较大，M4与M2分潮的振幅比已经接近多峰现象的临界条件。而广海湾独特的岛屿和近岸浅水地形，使浅海分潮的振幅进一步增大，形成低高潮的多峰现象。

Upon analyzing the measured tidal data from the Guanghai Bay, it was observed that there are multiple peaks during the low-high tide periods. Through water level reconstruction analysis using various tidal components, combined with other similar studies and mathematical results, it was found that a significant contributing factor to this phenomenon is the relatively large proportion of quarter-diurnal tidal components, such as M4, in the bay. The interaction among diurnal, semi-diurnal, and quarter-diurnal tidal components leads to this occurrence. By modifying factors such as tidal boundaries, nearshore water depth, and topography, numerical models are constructed to explore the reasons for the large amplitude of M4 tidal component. Results indicate that the primary reason for the large amplitude of M4 tidal component is its overall larger value in this region, the amplitude ratio of M4/M2 approaching the critical condition for multi-peak phenomena. Furthermore, the unique islands and nearshore shallow topography of Guanghai Bay amplify the shallow water tidal components amplitude, resulting in a multi-peak phenomenon at the low-high tide.