摘要
近年来,在四川盆地环"开江—梁平海槽"两侧礁、滩进行的油气勘探不断获得突破,发现了一批大型气藏,地震相与沉积相综合解释技术对上二叠统生物礁和下三叠统鲕滩的勘探突破发挥了重要作用,但针对下二叠统的滩相勘探一直没有新的突破。之前,对川西九龙山地区下二叠统栖霞组和茅口组的高能滩预测主要注重地质、测井研究,或利用地震反演方法开展储层预测,从未对茅口组、栖霞组进行地震相研究。为此,针对该区栖霞组和茅口组均为典型的碳酸盐缓坡沉积环境且不同的沉积环境具有不同的地震相特征,可利用地震相、沉积相综合解释技术,来预测有利的古地貌和沉积相带,进而预测高能滩的发育有利区。通过地震相特征分析,下二叠统具有3大地震相特征:①地震反射时间厚度异常增加;②下二叠统内部反射同相轴增多;③下二叠统底界明显超覆于志留系之上。利用这3种不同的地震相特征预测了有利于高能滩发育的古地貌区域。经实钻证实,采用该预测方法能够提高下二叠统高能滩储层的钻探成功率。
In recent years,the hydrocarbon exploration of reef and beach reservoirs is very successful on both sides of the 'Kaijiang-Liangping' trough in the Sichuan Basin,with the discovery of many large gas reservoirs.Integrated interpretation of seismic facies and sedimentary facies plays a key role in the breakthrough of exploration of the Upper Permian bioherm and the Lower Triassic oolitic beach reservoirs.However,the exploration of the Lower Permian reservoirs of beach facies is still unsuccessful.Previous prediction of high-energy beach facies in the Lower Permian Qixia and Maokou formations was mainly based on geologic and logging data or through seismic inversion,and no research was performed on their seismic facies.Both the Qixia and Maokou formations are typical deposits formed on carbonate ramp which shows unique characteristics of seismic facies,thus integrated interpretation technique of seismic facies and sedimentary facies can be used to predict favorable paleogeography and sedimentary facies belts,and further to recognize zones with well-developed reservoirs of high-energy beach facies.The Lower Permian shows 3 major features of seismic facies,including the increase of reflection time-thickness;the increase of reflection events within the Lower Permian;and the obvious overlapping of the lower boundary of the Lower Permian on the Silurian.These three features of seismic facies are used to predict favorable areas for the development of high-energy beach reservoirs.The drilling results verify the accuracy of the prediction.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2011年第6期42-45,124-125,共4页
Natural Gas Industry
关键词
四川盆地
西北
早二叠世
地震勘探
储集层
鲕滩
预测
Sichuan Basin,west,north,Early Permian,seismic exploration,reservoir,oolitic beach,prediction