【摘要】 松辽盆地徐家围子断陷多期次喷发的火山岩在纵向和横向上相互叠置,造成火山岩地震响应特征复杂,影响了对火山岩储层的地震预测精度和地质规律的认识.本文基于钻井和连片三维地震资料,结合区域构造认识,建立了徐家围子断陷营城组火山机构-岩相带的地震响应模式,并利用相干体和地层切片等属性分析技术实现了火山机构岩相带的空间识别.从火山口到远源相带火山岩体非均质性减弱,在三维相干体切片上表现为相干属性变化率的降低.研究区主要发育四种火山机构-岩相带,其地震响应特征分别为,①火山口穹窿多种岩相迭合相带:表现为杂乱反射带、自下而上呈放射状、围绕火山喷口厚度向外减薄、相干性强、剖面和平面形态多变;②近源爆发相与溢流相叠置相带:具有断续层状、中强振幅、低频反射特征,呈环带状围绕火口中心相带分布;③远源爆发相带:火山机构一侧具有上拱的板状外形,表现为楔形层状连续中强振幅反射特征;④远源火山沉积相带:具有板状外形,亚平行反射结构,能量较强和同相轴连续的响应特征.这些反射特征是火山作用喷出物堆积过程中,内部层结构和层形态呈规律性变化的地震表象.更多还原

【Abstract】 The complex seismic response features of volcanic formation,that was caused by multistage volcanic eruption and superimposed in the vertical and horizontal directions,affect the reservoir accuracy of seismic prediction and the cognition of geological laws in Xujiaweizi depression.Based on drilling and 3D seismic data,combined with the regional tectonics,this article establishes the seismic response model and identifies the spatial distribution of the volcanic edifice-facies zone by the technology of coherence and formation slice attribution.From the vents to the distal facies the volcanic body heterogeneity weakens,the rate of change reduces gradually in the coherence cube slices.There are four types of volcanic facies seismic response in the research area.The first type is multi-facies supoimposed zone of dome crater which shows the characteristics of messy reflective band and bottom-up radial shape.It also has the features of thinning out around the volcanic vents,strong coherence,varied forms in profile and plan view. The second type is near-source superimposed eruption and overflow facies that has the reflection characteristics of intermittent layering,moderate-high amplitude,and low frequency.It is distributed in bands around the crater.The third type is distal eruption facies that has the reflection characteristics of continuously layered wedge and strong amplitude.It has the arch plate shape adjacent to the side of the volcanic body.The fourth type is distal volcanic sedimentary facies that has the reflection characteristics of plate shape,sub-parallel reflection configuration,strong energy continuous phase axis.更多还原