摘要
松辽盆地南部深层发育2套火山岩,分布在下白垩统营城组下部和上侏罗统火石岭组中上部。东岭地区营城组为酸性岩,岩相以爆发相为主,占73%;火石岭组为中基性岩,可分为上下两段,岩相以喷溢相为主(上段占67%,下段占59%)。酸性岩在地震剖面上主要表现为透镜状、丘状反射特征,顶面为中强反射,内部为中强或弱反射,低频、杂乱、断续分布,具有明显的穿时现象。中基性岩在地震剖面表现为眼球状、丘状反射特征,顶部为强反射,与围岩呈超覆关系,内部为弱反射、蠕虫状、杂乱、低频、断续反射。利用拟声波曲线反演方法识别火山岩,其结果表明东岭地区火石岭组火山岩厚度受断层F1控制,在F1东侧薄,西侧厚,在SN109井区域最厚。利用构造趋势面分析和三维体切片技术可识别火山机构的火山锥。在东岭地区火石岭组发现2个火山锥发育区(以中部区域为主),该区火山锥面积为56 km2,最大幅度为547 m。利用倾角属性方法结合火山机构物理模型可识别出火山通道相和侵出相,波形分类方法可识别爆发相和喷溢相,结合两种方法可以准确地识别出火山岩相;其结果表明东岭地区火石岭组在中部区域喷溢相上部亚相和火山通道相发育。火山锥发育的区域是火山岩储层厚度发育的区域,同时岩相预测结果表明该区也是储层物性好的区域,所以东岭地区中部火山岩是勘探的有利目标区。
Both lower Cretaceous Yingcheng Formation and upper Jurassic Huoshiling Formation are partially composed of volcanic rocks in southern Songliao Basin. In Dongling area, most volcanic rocks of Yingcheng Formation are acidic and 73% of them belong to explosive facies while most volcanic rocks of Huoshiling Formation are basic. The volcanic rocks in Huoshiling Formation were divided into upper and lower series. 67% volcanic rocks of upper series are explosive facies and 59% volcanic rocks of lower series are explosive facies. Lenticular and mound shape, mid-strong or weak amplitude, low frequency,chaotic-bad continuity and diachronous phenomenon are the characteristics of seismic reflection for acidic rocks. The top boundary of acidic rocks shows a strong reflection. Eyeball and mound shape, weak reflection, worm like, low frequency, chaotic and bad continuity are characteristics of seismic reflection of basic rocks. Volcanic rocks were reeognised by using inversion of simulated AC curve. The results showed that fault F1 controlled the thickness of volcanic rocks and thicker in the west and thinner in the east. The thickest was around well SN109. Cones of volcanic edifices were reeognised by using trend surface of structure and 3D slice methods. Two cone-developed areas have been found in Huoshiling Formation. The cones distributed in 56 km^2 with structural amplitude of 547 m. Volcanic vent facies and extrusive facies were recognised with dip angle method based on the geophysical model of volcanic edifices. Explosive facies and effusive facies were recognised with waveform classification method. Integration of the dip angle method and waveform classification method recognises volcanic facies. The upper subfacies of effusive facies and volcanic vent facies well developed in the middle area of Huoshiling Formation. The cone-developed area is the first-rank target of volcanic prospect because of the thickest volcanic reservoirs and perfect permeability and porosity.
出处
《吉林大学学报(地球科学版)》
EI
CAS
CSCD
北大核心
2007年第6期1083-1090,共8页
Journal of Jilin University:Earth Science Edition
基金
国家"973"项目(2006CB701403)
关键词
松辽盆地南部
火石岭组
营城组
火山岩储层
拟声波曲线反演
Southern Songliao Basin
Huoshiling Formation
Yingcheng Formation
volcanic reservoirs
inversion of simulated AC curve