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为了阐明白云凹陷古近系恩平组的物源供给方式及沉积充填演化规律,以古地貌-古生物分析、LA-ICPMS锆石U-Pb定年、地震属性分析及典型地震相识别为主要技术手段,对白云凹陷恩平组不同沉积时期的沉积环境、古地貌特征、锆石形态及年代组成、砂体发育特征等进行分析,认为恩平组沉积时期其物源供给方式及沉积充填特征发生了明显的变化.恩平组SQ1~SQ2时期陆相断陷湖盆特征明显,沉积时期沉积范围较小,以盆内短程物源(中生代火成岩基底母岩)供给为主:南部陡坡带主要发育近源快速堆积而成的扇三角洲;北部缓坡带发育充填结构典型的辫状河三角洲及上倾尖灭明显的滩坝砂体.恩平组SQ3时期主要为半封闭的海湾沉积环境,沉积范围较大,以盆外远程物源(华南褶皱带前寒武纪-古生代变质岩基底母岩)供给为主:南部陡坡带断裂活动减弱,发育规模较小的扇三角洲;北部缓坡带发育沿北西-南东方向展布的三期前积反射并不断向盆地中心进积的典型大型辫状河三角洲.
In order to elucidate the provenance and depositional evolution of the Enping Formation in the Paleogene in the Baiyun Depression, taking the paleogeomorphology-paleontology analysis, LA-ICPMS zircon U-Pb dating, seismic attribute analysis and typical seismic facies identification as the main technical means , Analyzed the sedimentary environment, paleogeomorphology, zircon morphology and sand body development characteristics of Enping Formation at different depositional stages in the Baiyun Sag. It is concluded that the source and depositional characteristics of the Enping Formation during the sedimentary period of Enping Formation occurred Obvious changes in the Enping Formation.The terrestrial faulted lacustrine reservoirs from Enlightenment SQ1 ~ SQ2 are obviously characterized by a relatively small depositional range during the depositional period and are dominated by the supply of short-basin source rocks (Mesozoic igneous base rock): the main development in the southern steep slope Fan delta formed by rapid accumulation of source rocks in the northern ramp zone, typical braided river deltas with filling structure and obvious beach-bar sand body with overturned updip.Eng Ping Formation SQ3 period was mainly a semi-closed Gulf sedimentary environment with a relatively large sedimentary range Large, the source of extra-basin supplies (Precambrian-Paleozoic metamorphic basement rocks in the South China Fold Belt) are dominated by the weakening of the fault activity in the southern steep slope and the development of smaller fan delta ; Development along the northern part of the North West with a gentle slope - product reflection three-southeast trending ago and continue to accumulate into the center of the basin of the typical large braided river delta.