摘要
古城地区钻井资料欠缺。通过单井相分析、单井相标定地震相、地震相分析,研究了古城台地演化特征。台地的发育经历了缓坡—弱镶边台地—镶边台地的发育过程。从早寒武世到早中奥陶世,斜坡带的宽度依次变窄,台地边缘带的宽度呈变宽的趋势,并在地震反射外形上从初期的无明显外形特征演变到早中奥陶世的丘状外形。到中奥陶世末期,台地边缘演化到较高能型的台地边缘,但未到高能型的台地边缘。平面地震相分析表明,台地在演化过程中各相带的展布具有不规则性。研究区台地的演化属渐变过程,与塔中台地的类型形成鲜明对比。台地的沉积类型早期以相对静水沉积为主,逐渐发展到相对高能沉积。台地边缘碳酸盐岩建隆以灰泥丘为主,颗粒灰岩胶结良好,骨架礁体不发育。
For lack of drilling data in Gucheng area,study of carbonate platform has been carried out based on seismic facies assemblage analysis method,combined with sedimentary facies analysis of single drill and geological data.Platform has experienced three evolution stages,including slope,feeble edging carbonate platform and edging carbonate platform.From early Cambrian to early-middle Ordovician,the width of slope becomes narrower gradually,while platform edge becomes wider,with dome shape external edge.By the end of middle Ordovician,platform has been evolved with relative high energy.Analysis of planar seismic facies indicates that each facies is not distributed regularly in evolution process.The Gucheng carbonate platform evolves gradually,which was completely different from Tazhong carbonate platform.Carbonate builtup in platform edge is mainly composed of mud mound.The grains are well cemented and framework reef is not developed.
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2011年第1期115-121,共7页
Natural Gas Geoscience
