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中西太平洋海山区是太平洋板块上洋壳年龄最老、磁条带异常最复杂、海山分布最密集、地质构造最独特、构造活动最强烈的一个区域,为探讨区内众多海山的构造成因,以板块构造理论为指导运用弹性板挠曲理论计算了中西太平洋海山区岩石圈的有效弹性厚度.结果显示,研究区的有效弹性厚度总体上表现为北西高南东低的趋势,西边的麦哲伦海山链表现出南北低中间高的趋势,东边的中太平洋海山群呈现出由西往东厚度递减的现象,且这2个典型区域的岩石圈有效弹性厚度与现今法属玻利尼西亚群岛处的比较接近.据此推测它们是在白垩纪期间(约130～90Ma)形成于现今法属玻利尼西亚群岛处的大规模热点群附近,且受到了后期火山岩浆活动的改造作用.
In the western and western Pacific, the seamount area is one of the oldest oceanic crusts on the Pacific plate, with the most complicated magnetic stripe anomalies, the most densely distributed seamounts, the most unique geological structure and the strongest tectonic activity. In order to explore the tectonic causes of numerous seamounts in the area, Plate tectonics theory, the effective elastic thickness of the lithosphere in the central western and western Pacific is calculated by using the flexural plate theory of elastic plate.The results show that the effective elastic thickness of the study area generally shows a trend of low north west and south east, and the Magellan seamounts to the west show The trend of high in the middle and low in the north and south, east of the Central Pacific seamounts show a decreasing thickness from west to east, and the effective elastic thickness of the lithosphere in these two typical areas is similar to that of the French Polynesia at this time. It is speculated that they formed during the Cretaceous (about 130 ~ 90Ma) near the current large-scale hotspot at the French Polynesian archipelago and were remodeled by later volcanic activity.