The Glutenite Sedimentary Facies and Hydrocarbon Distribution in the Upper Fourth Member of Shahejie Formation in Shengtuo Area

Key words: 
• Key words Shengtuo area /
• glutenite /
• prograded-type fan delta /
• depositional model /
• hydrocarbon accumulation

Abstract: Abstract Glutenite fans are the major sedimentary systems in the upper fourth member of Shahejie formation in Shengtuo area, and different turbiditic glutenites develop in the deep lacustrine environment. On the base of cores observation and description, combined with the numerous data of well logging, sedimentary characteristics are studied in the upper fourth member of Shahejie formation in Shengtuo area, and the hydrocarbon distribution is analysed. The results show that the prograded-type fan delta is the major sedimentary system in the downdropped block of contemporaneous fault in Shengtuo area. The gravity channel and slump develop simultaneously. The glutenite reservoirs successively distribute lithologic hydrocarbon reservoir,structural hydrocarbon reservoir,stratigraphic hydrocarbon reservoir from the central subsag to the marginal facies belt. The hydrocarbon distribution is controlled by sedimentary facies apparently. The variance of reservoir quality is obviously in different facies belt. The reservoir quality is the best in middle fans, and they are the favorable places for hydrocarbon accumulation. The slumps and gravity channels take second place. The oiliness quality of inner fans and outer fans are bad because of bad reservoir quality. In addition, the inherited deep subsag and the partition of lithology have effects on hydrocarbon distribution.