滴西—五彩湾地区石炭系火山岩岩相特征研究

The Lithofacies of Carboniferous Volcanic Rocks in Dixi-Wucaiwan Area

准噶尔盆地滴西—五彩湾地区石炭系火山岩岩相复杂,其分布规律的研究难度较大。在岩芯观察、薄片鉴定、录井、测井资料及扫描电镜分析的基础上,建立了准噶尔盆地滴西—五彩湾地区石炭系火山岩识别图版并对主要火山岩储层的测井响应特征进行了研究;在对滴西地区5口典型探井的单井相详细分析基础上,研究了该区剖面火山岩岩性及岩相分布特征。在此基础上,查明了滴西—五彩湾地区石炭系火山岩岩相特征及其分布规律:研究区北部主要发育凝灰岩及砂泥岩,期间夹有条带状中性火山岩、基性火山岩及少量火山角砾岩;中部主要发育凝灰岩、中性火山岩、凝灰质砂泥岩,夹有团块状酸性侵入岩、酸性火山岩、火山角砾岩;南部主要发育砂泥岩、凝灰岩,夹有条带状凝灰质砂泥岩、基性火山岩、团块状中性火山岩及少量火山角砾岩。由于不同的火山岩岩相具有不同的储集性能,这种平面分布特征的研究对油气勘探具有积极的意义。

The complex volcanic rock types of carboniferous volcanic reservoir in Dixi Wucaiwan area,Junggar Basin have made further research on the volcanic rock lithology and lithofacies distribution characteristics difficult. Based on the core observation,thin section identification,logging,well logging data,and scanning electron microscopy(SEM),the responses of well logging were analyzed. The methods of lithology identification for volcanic rock were established. Furthermore,by analyzing the features of single well facies of 5 typical wells and section phase,the lithology and lithofacies distribution characteristics were studied. The results revealed that the north of study area is mainly tuff and sand-mudstone intermingled with intermediate volcanic rocks,basic volcanic rocks and volcanic breccia. What develops in the central part are tuff,intermediate volcanic rocks,tuffaceous sand,with crumb acidic intrusive rocks,acidic volcanic rocks and volcanic breccia. In the southern part,sand-mudstone and tuff are distributed ,with tuffaceous sand mudstone,basic volcanic rocks,crumby intermediate volcanic rocks and volcanic breccia. Due to the different reservoir performance of different volcanic facies,the research on the plane distribution features is of positive significance to oil and gas exploration.