在前人研究的基础上,以层序地层学基本原理为指导,根据地震、测井和古生物资料,对珠江口盆地番禺低隆起一白云凹陷北坡及其周围地区早中新世-中中新世地层进行了系统的层序地层分析,认为区内层序地层发育受控于特殊的古地理位置--陆架坡折.由于陆架坡折带位置从21 Ma以来基本处在白云凹陷北坡附近,使得该区长期处于陆架坡折以下的斜坡深水环境,在低海平面时期发育了大量低水位体系域沉积体.以SQ21.0层序陆架坡折带为重点,通过多种研究手段,确定出陆架坡折带的分布范围,并识别出陆架坡折带控制的低位体系域主要沉积体,主要有陆架边缘三角洲(或低位楔、低位三角洲)、水道充填和低位扇等3种类型,并对其特征及展布进行了初步研究,提出了2个极具潜力的勘探领域--隐形构造圈闭和岩性圈闭.%On a basis of previous studies and sequence stratigraphy principles, a systematic analysis of sequence stratigraphy was conducted for the early-middle Miocene sediments in Panyu low-uplift, the north slope of Baiyun sag and their surrounding areas according to seismic, log and paleontology data, and it was suggested that the development of sedimentary sequences here was controlled by a speical palaeotopographic feature-the shelf break. Because the shelf break has largely been located near the north slope of Baiyun sag since 21.0 Ma, this studied region was in a deep-water environment beneath the shelf break for a long time, and a lot of sedimentary bodies of lowstand system tracts developed during lower sea level. By focussing on the shelf break zone in SQ21.0 sequence and using multiple tools, the shelf break extension is determined, and the major sedimentary bodies of lowstand system tracts controlled by the shelf break are recognized, mainly including three types such as shelfmargin delta (or lowstand wedge, lowstand delta), incised channel deposits and lowstand fan. Their characteristics and extension are preliminarily studied, suggesting two types of prospects with high exploration potential, i. e. subtle structural trap and lithological trap.
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