川西坳陷丰谷构造须四段沉积微相及沉积演化
|
摘要
川西坳陷丰谷构造须家河组四段属典型的陆相含煤地层,广泛发育辫状河三角洲沉积。首先根据岩心描述、岩石薄片观察及砂体测井曲线形态分析等,在须四段识别出水下分流河道、分流河道间、河口坝、远砂坝、水下天然堤和前三角洲泥等6种沉积微相;其次针对丰谷构造井资料较少、砂泥岩速度差异不大的特点,采用神经网络的地震多属性反演得到自然伽马数据体;最后,以次为约束,建立泥质质量分数三维模型,预测泥质质量分数的空间变化,分析沉积微相演化规律。研究表明:须四段垂向经历了完整的水进—水退过程;沉积早期和晚期砂体较厚,主要为多期水下分流河道的拼接和叠置;沉积中期砂体相对较薄,发育河口坝与残余水下分流河道,砂体间有厚度稳定的前三角洲泥。
The fourth section of Xujiahe Formation in Fenggu Structure of western Sichuan Depression is typical continental coal-bearing strata and widely develops the braided river delta.According to core description,rock slice observation,analysis of logging curve shape,underwater distributary channel,inter distributary,mouth bar,distal bar,underwater natural levee and prodelta mud are identified in the fourth section of Xujiahe Formation.In view of little well data and small velocity difference between sandstone and mud in Fenggu Stucture,the data volume of natural gamma is inverted by using multiple seismic-attributes inversion based on neural network.Three-dimensional model of shale content is established in order to predict the spatial variation of shale content and to analyze the evolution law of sedimentary microfacies.The results show that the fourth section of Xujiahe Formation experiences the complete process of transgression to regression.At the early stage and late stage of deposition,sand bodies are very thick and are mainly the splice and superimposition of multiphase underwater distributary channel.At the middle stage of deposition,sand bodies are relatively thin and mouth bar and residual underwater distributary channel develop and stably thick prodelta mud distributes among sand bodies.
The fourth section of Xujiahe Formation in Fenggu Structure of western Sichuan Depression is typical continental coal-bearing strata and widely develops the braided river delta.According to core description,rock slice observation,analysis of logging curve shape,underwater distributary channel,inter distributary,mouth bar,distal bar,underwater natural levee and prodelta mud are identified in the fourth section of Xujiahe Formation.In view of little well data and small velocity difference between sandstone and mud in Fenggu Stucture,the data volume of natural gamma is inverted by using multiple seismic-attributes inversion based on neural network.Three-dimensional model of shale content is established in order to predict the spatial variation of shale content and to analyze the evolution law of sedimentary microfacies.The results show that the fourth section of Xujiahe Formation experiences the complete process of transgression to regression.At the early stage and late stage of deposition,sand bodies are very thick and are mainly the splice and superimposition of multiphase underwater distributary channel.At the middle stage of deposition,sand bodies are relatively thin and mouth bar and residual underwater distributary channel develop and stably thick prodelta mud distributes among sand bodies.
引文
[1]林良彪.川西前陆盆地上三叠统须家河组沉积相及岩相古地理演化[D].成都:成都理工大学,2005:48-68.Lin Liangbiao.Sedimentary facies and paleogeographic evolution of theUpper Triassic Xujiahe Formation in West Sichuan Foreland Basin[D].Chengdu:Chengdu University of Technology,2005:48-68.
[2]李在光,杨占龙,刘俊田,等.多属性综合方法预测含油气性及其效果[J].天然气地球科学,2006,17(5):727-730.Li Zaiguang,Yang Zhanlong,Liu Juntian,et al.The prediction of theoil-gas through multi-component comprehensive method and effects[J].Natural Gas Geoscience,2006,17(5):727-730.
[3]赵政璋,赵贤正,王英民,等.储层地震预测理论与实践[M].北京:科学出版社,2004:278-282.Zhao Zhengzhang,Zhao Xianzheng,Wang Yingmin,et al.Theory andpractice of reservior′s seismic prediction[M].Beijing:Science Press,2004:278-282.
[4]Daniel P,Hampson James S,Schuelke John A,et al.Use of multiattribute transforms to predict log properties from seismic data[J].Geophysics,2001,66(1):2035-2041.
[5]Quincy Chen,Steve Sidney.Seismic attribute technology for eservoirforecasting and monitoring[J].The Leading Edge,1997,16(5):445-456.
[2]李在光,杨占龙,刘俊田,等.多属性综合方法预测含油气性及其效果[J].天然气地球科学,2006,17(5):727-730.Li Zaiguang,Yang Zhanlong,Liu Juntian,et al.The prediction of theoil-gas through multi-component comprehensive method and effects[J].Natural Gas Geoscience,2006,17(5):727-730.
[3]赵政璋,赵贤正,王英民,等.储层地震预测理论与实践[M].北京:科学出版社,2004:278-282.Zhao Zhengzhang,Zhao Xianzheng,Wang Yingmin,et al.Theory andpractice of reservior′s seismic prediction[M].Beijing:Science Press,2004:278-282.
[4]Daniel P,Hampson James S,Schuelke John A,et al.Use of multiattribute transforms to predict log properties from seismic data[J].Geophysics,2001,66(1):2035-2041.
[5]Quincy Chen,Steve Sidney.Seismic attribute technology for eservoirforecasting and monitoring[J].The Leading Edge,1997,16(5):445-456.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心