摘要
层序界面的形成伴随着剥蚀夷平、水道下切、构造抬升等古地貌改造作用 ;层序的样式、层序 -体系域 -准层序的平面分布及削截、超覆尖灭、前积角度、退积幅度等地震反射特征也受古地貌的直接影响 .因而 ,层序地层提供了可供古地貌分析的信息 .通过对塔河油田石炭系层序地层研究 ,应用初始海泛面、最大海泛面上超尖灭线、坡折线、褶皱形态等标志 ,识别了SQ1、SQ3层序发育时期的隆起、差异压实低凸起、斜坡、缓坡、凹陷等古地貌单元 ,揭示了SQ3层序发育之前的构造挤压活动 ,应用Ⅱ油组的砂体平面分布验证了古地貌分析结果 .综合上述分析 ,SQ1、SQ3层序发育时期 ,斜坡带和凹陷带有助于低位体系域砂体局部聚集 ,是研究区岩性圈闭发育的有利场所 .
The development of sequence boundaries is usually associated with the eroding peneplaining, fluvial downcutting and tectonic uplifting processes which causes a great reforming of paleogeomorphy. By contrast, sequence patterns and the distributions of the sequences, their systems tracts and parasequences are influenced by paleogeomorphy, indicated by reflection characteristics such as truncation, lapout, progradation angle, regression scope on seismic sections. The sequence stratigraphy analysis here, therefore, provides a powerful tool to identify the paleogeomorphies. Based on the research on the sequence stratigraphy of the Carboniferous, Tahe oilfield, the marks of the onlap pinch-out lines of the first flooding surface and the maximum flooding surface, slope-break lines and folding shapes have been applied to identify the different paleogeomorphic units such as the uplifts, warps of differential compaction, moderately angled slopes, gently angled slopes and depressions during SQ1 and SQ3 sequence developments, firstly revealing an uplifting event caused by tectonic compression before SQ3 sequence. Meanwhile, the planar distribution of sand-bodies of the Ⅱ oil-unit has also been used to verify the results of paleogeomorphy. Through the synthetic analysis above, the authors have found that the sand bodies in lower systems tracts of SQ1 and SQ3 sequence are mainly distributed in the slopes and the depressions consist of the favorable sites of the lithologic trapping target.
出处
《地球科学（中国地质大学学报）》
EI
CAS
CSCD
北大核心
2003年第4期425-430,共6页
Earth Science-Journal of China University of Geosciences
关键词
层序地层学
古地貌
塔河油田
sequence stratigraphy
paleogeomorphy
Tahe oilfield.
