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南沙群岛及其邻近海区近１８．５万年以来气候与环境非线性研究表明曾发生三次明显气候转变，形成四个映射区。其中氧同位素第５期与第４期转变较明显，其次是氧同位素第６期与第５期的转变，最后是第３与第２期之间的变化，这与全球第四纪古气候研究结果是一致的，得到了氧同位素和古生物资料的进一步印证。半深海－深海海底沉积物有机质演化阶段在海进海退过程中表现出垂直分带和非线性变化。上陆坡以氧化堆积带为主，有机质供给多、但消耗迅速且水动力相对强；中陆坡为利于有机质保存的还原带；下陆坡为有机质缩合阶段，陆坡下缘－远洋为有机质沉降氧化带与沉积埋藏阶段的植烷形成带。这几个带在古气候、古海平面非线性变化中是沿海底向上或向下迁移的，其变化是非线性的。
Nansha Islands and its adjacent sea areas Nearly 185,000 years of non-linear climate and environmental studies have shown that there have been three significant changes in climate, the formation of four mapping area. Among them, the fifth and fourth oxygen isotope transitions are more obvious, followed by the sixth and fifth oxygen isotope transitions, and finally the third and the second changes, which are related to the Quaternary Paleoclimatic Research The results are consistent and further evidence of oxygen isotopes and palaeontology has been obtained. Semi-deep sea-deep sea sediment evolution stage of organic matter in the sea into the process of regression showed vertical zoning and nonlinear changes. On the up slope, the oxidation accumulation zone is the main component, and the organic matter is supplied more, but the consumption is rapid and the hydrodynamic force is relatively high. The middle slope is the reduction zone for the preservation of organic matter. The lower slope is the organic matter condensation stage. Sedimentary burial stage of phytane formation zone. In the paleoclimate and paleoclimate, the non-linear changes of the paleo-sea level migrate upward or downward along the sea floor, and the changes are nonlinear.