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南沙群岛永暑礁小■湖“南永3井”沉积柱样长5．90m，沉积物为泛灰黄的白色，岩性松散，未胶结，主要为粉砂质砂，少量为砂、砂质粉砂和粉砂－砂，常含小砾石。沉积物由珊瑚类为主的生物碎屑组成，分选性差，负偏态值和双峰态等均表明沉积物搬运距离不远、水动力条件较弱的特点。柱样底部 TIMS U系年龄为 1682±15 a B．P。对照有关文献，发现该井沉积跨越了小冰期D至现代气候最适宜期A等4个小气候期，其沉积物粒度百分含量变化趋势可以作为气候变化的替代性指标。
Nansha Islands Yongshuijiao small ■ Lake “Nanyong 3 well” Sedimentary column length 5.90m, the sediment is a pan-gray yellow, lithology loose, not cementing, mainly silty sand, a small amount of sand, sand Silty sand and silt - sand, often containing small gravel. Sediments are composed of coral-dominated biological clays. Poorly sorted, negatively-biased and bi-modal sediments indicate that the sediment transport distance is not long and the hydrodynamic conditions are weak. The TIMS U-series at the bottom of the column was 1682 ± 15 a B. P. According to the relevant literature, it is found that the well is deposited across four microclimate periods, ie, the small ice age D to the most suitable period A of modern climate. The trend of sediment particle size percentage can be used as an alternative indicator of climate change.