江苏高邮凹陷深凹带古近系戴南组地震沉积学

Seismic Sedimentology of the Palaeogene Dainan Formation in the Deep Sag Zone of Gaoyou Depression, Jiangsu Province

江苏高邮凹陷石油地质条件优越,但构造复杂,沉积类型多样,砂体沉积厚度薄,横向变化快。根据地震沉积学基本原理与方法,在等时层序地层格架内,运用90°相位转化、分频处理、属性优选及地层切片等关键技术,对高邮凹陷深凹带戴南组储集砂体进行了识别与描述。通过对典型地层切片进行精细地质解释与标定,明确各沉积体系发育特征及其演化规律,并最终建立了适用于断陷湖盆沉积充填的沉积模式。

Seismic sedimentology is a newly emerged interdisciplinary subject, which uses seismic data to gain insights into the rocksand their forming processes. It is regarded as an effective tool for mapping high-frequency sequence and depositional systems, andplays an important role in the exploration and production of thin sandstone reservoirs. Because of the scarcity of well data in the deepsag zone, the distribution and the scale of the sandstone reservoir in the deep sag zone are very difficult to determine by using theconventional exploration method. Guided by the third-order sequence-stratigraphic correlations from seismic and wire-line log data, inthis study, stratum slices were prepared from a three-dimensional seismic volume to reveal sand-body distribution in the deep sag zoneand to map the associated depositional systems distributions in slopes of the depression. With the assistance of the comprehensiveanalysis of core, lithology and well-logging data, the slump turbidite sandstone reservoirs of different sequences in the deep sag zonewere effectively predicted.