乌伦古坳陷深层石炭系火山岩低频地震识别技术应用

The application of low frequency seismic identification technology to deep Carboniferous volcanic rocks in Wulungu depression

乌伦古坳陷石炭系火山岩储层是准噶尔盆地油气勘探的重要目的层系,然而由于埋藏深,岩性复杂,受后期改造作用影响大,依靠以往二维地震勘探技术难以刻画火山岩体展布。文中以低频可控震源采集获得的地震资料为主,对乌伦古坳陷北部区域石炭系火山岩分布特征进行了研究。鉴于低频信息在地震深层成像方面的优势以及叠加剖面对构造趋势的良好反映,笔者利用低频段叠加剖面进行波场识别,指导偏移剖面解释,并将地质、地震、钻井资料相结合开展火山岩识别的研究,总结出了该区火山岩相的地震响应特征,综合利用地震反射特征和地震属性分析等手段,对火山岩体展布进行了识别刻画。本次研究探索了适用于深埋复杂岩性条件的火山岩储层低频地震识别方法,为该区石炭系油气勘探提供了一定的依据。

The Carboniferous volcanic reservoir in Wulungu depression is an important target stratum for hydrocarbon exploration in Junggar Basin.However,due to its deep burial,complex lithology and strong late reformation,it is difficult to depict the distribution of volcanic rock masses by relying on the previous two?dimensional seismic exploration technology.Mainly based on the seismic data col?lected by low frequency vibroseis,the authors studied the distribution characteristics of Carboniferous volcanic rocks in the northern part of Wulungu depression.In view of the advantages of low?frequency information in deep?layer imaging and the good reflection of stacked section to structural trends,low?frequency stack section was used to identify wave field,which can guide migration section interpretation.Then by combining geological,seismic and drilling data,research on volcanic rock identification was carried out.The seismic response characteristics of volcanic facies in this area were summarized.The distribution of volcanic rocks was identified and characterized by means of seismic reflection characteristics and seismic attribute analysis.A low?frequency seismic identification method for volcanic res?ervoirs suitable for deep?buried complex lithologic conditions is explored.It provides a basis for Carboniferous oil and gas exploration in this area.