Fault sealing of south-west gentle slope belt in Huimin depression

Key words:  Huimin depression  gentle slope belt  fault sealing  shale smear  sealed pressure

Abstract:

In order to study the role of fault on hydrocarbon accumulation of south-west gentle slope in Huimin depression，the fault sealing was researched through clay smearing factor and fault plane pressure combined with sand-clay ratio method based on the analysis of development characteristics of oil-controlled fault in gentle slope. The results show that the fault sealing in this area shows a great difference in time and space, and plays different roles in hydrocarbon migration and accumulation. Xiakou fault controls oil migrating to the gentle slope. The poor fault sealing of east section can form hydrocarbon migration channel through connecting source rock and trap，while the fault sealing of west section is good，which can form reservoirs by preventing hydrocarbon from migrating. The third or fourth grade faults within gentle slope control hydrocarbon migration and accumulation layer. Further exploration targets should be focused on the fault-block traps in the Es4 formation in the northern of the study area.