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对南沙群岛海域８７－１１柱样天然剩余磁化强度（ＮＲＭ）及９０－１０３柱样ＮＲＭ、磁化率（ｘ）、剩磁倾角（Ⅰ）等的功率谱分析表明：晚更新世以来该区沉积物的古地磁参数较好地反映了古气候、古环境的变化，响应着古气候变化的米兰科维奇天文学周期；在周期成分中，以地球轨道偏心率周期（ｅ）及岁差周期（ｐ）为主，地轴倾斜度周期（ε）无明显表现，同时获得了与特殊地球位置相关联的岁差半周期成分。研究还表明，古地磁参数存在着明显的对古气候变化的非线性响应，明显不同于开阔大洋；同时，不同的沉积单元，沉积物古地磁参数对古气候变化响应的灵敏度各不相同。
The power spectrum analysis of natural residual magnetization (NRM) of 87-11 column and NR column of 90-103, magnetic susceptibility (x), residual magnetocence (Ⅰ) and so on in the Nansha Islands shows that sediments of this area since the Late Pleistocene The palaeomagnetic parameters reflect the Paleoclimate and Paleoenvironmental changes and the Milankovitch astronomical period in response to paleoclimatic changes. In the periodic composition, the geomagnetic parameters of the Earth’s orbit (e) and precession period (p ), The geosynclinal gradient period (ε) shows no significant effect, and the precession half-period component associated with the special earth position is obtained. The study also shows that paleomagnetic parameters have significant nonlinear response to paleoclimate changes, which is obviously different from open ocean. At the same time, the sensitivity of palaeomagnetic parameters to paleoclimate changes is different for different sedimentary units and sediments.