【摘要】 利用二维地震和钻井、测井资料探讨了北波拿巴盆地东北部侏罗纪各时期的古地貌和沉积相特征。整个侏罗纪时期,研究区整体处于裂陷作用的构造环境,发育由陆相至海相的5个三级层序。早侏罗世早期的古地貌主要受控于北西向构造格局,沉积中心主要是北西走向的凹陷和向斜。早侏罗世晚期开始,北东向构造开始发育,同时盆地整体剧烈沉降,北西和北东走向的构造单元发生切割和冲突,导致其内部的构造分区十分零碎。中侏罗世末期盆地北部发生大面积抬升形成Callovian不整合,之后的构造活动比较稳定,同时北东向构造基本形成,研究区进入缓慢拗陷时期。在此构造演化背景下,北波拿巴盆地东北部在早—中侏罗世主要是陆相的河流相和冲积扇沉积,中侏罗世主要是海陆过渡相的扇三角洲和三角洲沉积,而晚侏罗世则主要是浅海和滨岸沉积。更多还原

【Abstract】 Based on the analysis of 2-D seismic,drilling and logging data,the tectonic environment was in rifting during the Jurassic period in the whole northeastern part of North Bonaparte Basin,Australia.Five 3rd-graded sequences have been identified from continental to marine environments in Jurassic sedimentary rocks.During the early stage of Early Jurassic epoch,the sedimentary center was mainly in the NW-trending sag and syncline under the control of NW-trending structures.During the late stage of Early Jurassic epoch,NE-trending structures began to develop and the whole basin was subsided rapidly,which resulted in the internal structures cut into fragmented areas since NW-trending units were collided with NE trending units.At the end of Middle Jurassic,the Callovian Unconformity developed and NW-trending structures formed as wide uplifting in the northern part of the basin,after which this region turned to be stable and entered into the phase of slow depression.Under this background of tectonic evolution,fluvial and alluvial fan facies mainly deposited during Early to Middle Jurassic epoch,transitional fan-delta and delta facies deposited during Middle Jurassic epoch,and neritic and littoral facies did during Late Jurassic epoch.更多还原