Abstract:

Muglad Basin of Sudan is an important hydrocarbon accumulation zones，and influenced by the regional structure，the Early Cretaceous sedimentary reservoir developed evolution is closely related with tectonic evolution. On a basis of the comprehensive study of the seismic，well logging and core data，the characteristics of sedimentary sequence of the Early Cretaceous of the western trend of block 4 in Muglad Basin and its controlling factors are studied. The main results and achievement are as follows：(1) The basin has experienced three large rift movements and three thermal subsidence depression movements of postrift stage，and formed 6 secondary-order sequences. In those secondary-order sequence stratigraphic frameworks，the target formations from Cretaceous Abu Gabra to Paleogene Adok are divided into 13 third-order sequences; (2) Lacustrine and braided delta sedimentary systems mainly developed at rift stages, and braided river and delta sedimentary systems mainly developed at sag stages; (3) The study shows that the sedimentary systems development of different sequence are mainly controlled by the synsedimentary fault and tectonic evolution of rift and sag stages.

Key words: Muglad Basin, the western trend of block 4, Early Cretaceous, sedimentary sequence, controlling factor