陆架边缘三角洲是三角洲动态分类中一种比较重要的三角洲类型，已经成为科学研究和勘探开发的热点。根据驱动因素，可将陆架边缘三角洲分为物源供给驱动型和可容纳空间驱动型两类。珠江口盆地距今21 Ma和13.8 Ma时期具备发育陆架边缘三角洲的地质条件。通过对录井、测井曲线和地震资料的综合分析，从地形、相对海平面变化和沉积物供给三方面对21 Ma和13.8 Ma进行对比，对陆架边缘三角洲形成条件进行了分析，认为21 Ma时期为物源供给驱动型，而13.8 Ma时期为可容纳空间驱动型。虽然层序SQ2和SQ9在地形、相对海平面变化和沉积物供给三方面都存在较大差异，但它们都为典型的Ⅰ型层序，发育低位扇体、陆架边缘三角洲和三角洲前缘的滑塌体，均为稳定的陆架边缘三角洲。%Shelf-margin delta,an important type in the dynamic classification of delta ,has become the focus of science re-searches and hot spot in oil&gas exploration .According to the driving factors ,shelf-margin delta can be categorized into two types,namely sediment supply-driving delta and accommodation-driving delta.The Pearl River Mouth Basin had fa-vorable geological condition for shelf-margin delta development at 21 Ma and 13.8 Ma.Shelf-margin deltas(21 Ma and 13.8 Ma)are analyzed in respects of topography ,relative sea-level change and sediment supply through integration of well log-ging,logging curves and seismic data .The forming condition analysis shows that the delta at 21 Ma is of sediment supply-dri-ving type,while the delta at 13.8 Ma is of accommodation-driving type.Although SQ2 and SQ9 are obviously different in respects of topography,relative sea-level change and sediment supply,they both are type I sequences,and have well-developed lowstand fans,shelf-margin delta and delta-front slumping deposits,which belonging to stable shelf-margin deltas.
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