苏丹Fula坳陷同裂谷期构造格局和沉积体系分布

Muglad盆地Fula坳陷是一个发育于晚侏罗世—早白垩世的裂谷盆地,发育着3条较大的同沉积断裂和东、西两侧的控盆边界断层,这些断裂将盆地分割成"两凹一隆两斜坡"的构造格局.Fu-la坳陷内部次级构造单元包括南部断阶带、南部凹陷、中部构造带、北部凹陷和北部断阶带"三正两负"5个二级构造带.盆地断裂的差异活动控制着沉积地层厚度、水体深浅和沉积格局的变化.同裂谷早中期,Fula坳陷发育河流、三角洲和近岸水下扇沉积,主要物源来自盆地北部;同裂谷中晚期,Fula坳陷发育扇三角洲、三角洲和近岸水下扇沉积,但主要物源来自盆地南部.最后,明确了生储盖组合特征,预测了有利储层分布地区.

Tectonic framework and depositional system distribution of syn-rift in Fula Depression,Muglad Basin,Sudan

Fula Depression in Muglad is a rift basin developed in late Jurassic and early Cretaceous.There are three major contemporaneous sedimentary faults and two boundary faults in the eastern and western sides of the basin,and these faults make the depression form the tectonic framework of two sub-depression,one uplift and two slopes.Fula Depression consists of south faulted belt,south sag,central tectonic belt,north sag and north faulted belt.The different activity of the faults controls the thickness of Cretaceous,water depth and sedimentary setting.In the early stage of the syn-rift,the fluvial,delta and nearshore subaquceous fan are developed in Fula Depression,the main material source is in the north of the basin;in the middle--late stage of the syn-rift,fan delta,delta and nearshore subaquceous fan are developed,but the main material source is in the south of the basin.Lastly,the association of source rock,reservoir and cap is determined and the favorable reservoir is predicted.