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南海北部MD05-2904孔末次冰盛期以来黏土矿物学的高分辨率分析表明,伊利石(29%～48%)、蒙脱石(14%～45%)、绿泥石(17%～28%)和少量高岭石(6%～14%)构成了该孔的黏土矿物组合,其时间序列变化不具冰期-间冰期的旋回特征.物源区分析显示,MD05-2904孔的蒙脱石几乎全部都是源自吕宋岛,全部高岭石都是源自珠江,而伊利石和绿泥石分别由珠江和台湾岛提供.根据同这3个主要物源区和南海表层现代沉积物中黏土矿物成分的对比,采用伊利石结晶度的线性剥离方法,建立了各主要物源区对南海北部陆坡黏土矿物相对贡献量的时间序列变化.研究结果发现,吕宋岛和台湾岛的贡献在24.1～17.5kaBP都维持在30%～40%,而珠江的贡献平均仅有25%;在进入17.5～14.0kaBP后,吕宋岛的贡献快速降为20%～25%,台湾岛的贡献从18kaBP的平均25%上升至平均35%,而珠江的贡献上升为平均40%;在进入全新世后,这3个主要物源区的贡献显著差异化,吕宋岛的贡献小幅上升并维持在27%～35%,台湾岛的贡献快速上升并维持在55%～60%,而珠江的贡献逐渐回落至全新世中晚期的平均15%.各物源区的黏土矿物贡献可能受黏土矿物形成、季风降雨剥蚀、洋流搬运能力、以及海平面变化等多种因素影响.
High resolution analysis of clay mineralogy since the last ice age of MD05-2904 borehole in the northern South China Sea shows that illite (29% -48%), smectite (14% -45%), chlorite (17% -28% %) And a small amount of kaolinite (6% -14%) constitute the clay mineral assemblage of the pore, and its time series variation is not characterized by the glacial-interglacial cycle characteristics. Analysis of provenance shows that the MM05-2904 montmorillonite Almost all of them originate from Luzon, all kaolinite originated from the Pearl River, and illite and chlorite from the Pearl River and Taiwan Island, respectively.According to these three major provenances and modern sediments in the surface of the South China Sea By comparing the compositions of clay minerals with linear delamination methods of illite crystallinity, the time series changes of the relative contributions of clay minerals to the continental slope in the northern South China Sea have been established. The results show that the contribution of Luzon Island and Taiwan Island is 24.1 ~ 17.5kaBP are maintained at 30% ~ 40%, while the contribution of the Pearl River averages only 25%; After entering the 17.5 ~ 14.0kaBP, the contribution of Luzon quickly reduced to 20% ~ 25%, Taiwan Island’s contribution from The average 25% of 18kaBP rose to an average of 35%, while the contribution of the Pearl River rose to an average of 40%. After entering the Holocene, these 3 The contribution of the major source areas significantly differentiated. The contribution of Luzon Island rose slightly and remained at 27% -35%. The contribution of Taiwan Island rose rapidly and remained at 55% -60%, while the contribution of the Pearl River gradually dropped back to the Holocene The average 15% of the middle and late period.The contribution of clay minerals in each provenance area may be affected by many factors, such as clay mineral formation, monsoon rainfall erosion, ocean current carrying capacity and sea level change.