摘要
以高分辨率层序地层学理论为指导,以野外地质露头剖面精细观察研究结合钻井、测井资料的综合研究为基础,详细研究了四川龙门山前陆盆地上三叠统小塘子组、须家河组的高分辨率层序地层学特征及其与沉积体系时空展布和演化规律的关系。从中识别出37个短期、12个中期、5个长期和1个超长期基准面旋回层序。将短期、中期基准面旋回层序细分为向上“变深”的非对称型、向上变浅的非对称型和对称型三种基本层序类型。论述了各级次基准面旋回层序的垂向序列、岩性岩相组合、结构类型和叠加样式等特征。在此基础上,对龙门山前陆盆地上三叠统小塘子组、须家河组地层进行高分辨率层序地层等时对比,建立了等时地层格架。详细讨论了层序地层格架中的生储盖组合特征。认为上三叠统小塘子组、须家河组地层具有良好的生储盖层组合和形成大、中型次生油气藏的条件。为确定龙门山前陆盆地上三叠统地层深层区的生储盖组合特征和开展储层预测与评价提供了重要依据。
On the basis of a comprehensive study of outcrops, core, log well and seismic data, taking the highresolution sequence stratigraphic theory as a direction, the authors analyse the high-resolution sequence stratigraphic characteristics of the Xiaotangzi Formation and Xujiahe Formation in Upper Triassic of Longmenshan foreland basin, western Sichuan.Three order base-level cycles are recognized from Xiaotangzi Formation and Xujiahe Formation, which consist of 37 short term, 12 mid-term, 5 long-term base-level cycles and 1 superlong term cycle sequences. According to the analysis of sequence boundary and microfaeies sequence, the short-term and mid-term stratigraphic base-level cycles can be divided into three types of structure, which is deepening upward nonsymmetric, shallowing upward nonsymmetric and symmetric stratigraphic base-level cycles sequences. Based on these studies, the vertical sequence, facies association, lithologic composition, structure type and stacking pattern are discussed in this paper, which lay an important foundation for defining the quality of the source-reservior-cap rock assemblies and forecasting petroleum and gas accumulation.
出处
《资源与产业》
2006年第2期119-124,共6页
Resources & Industries
基金
国家自然科学基金资助项目(40272012)
关键词
高分辨率层序地层学
基准面旋回层序
层序结构样式
沉积体系
上三叠统
四川龙门山前陆盆地
high-resolution sequence stratigraphy
base-level cycles sequences
cycle structure type
depositional sequence
Upper Triassic Longrnenshan foreland basin
western Sichuan
