Abstract:

By establishing functional relation between shale gouge ratio (SGR) value of fault zone and the height of oil column laterally sealed by fault, the discussion on quantitative evaluation method of fault lateral seal ability is carried out and the lateral seal ability of faults in Beier depression is studied quantitatively. The results show that SGR value of fault zone has exponential relation with oil column height which is sealed by it, and fault lateral seal ability depends on 3-dimension distribution of SGR value of fault plane. By using the function formula of lateral seal-failure envelopes of faults established by data of reservoir in Bei 301 block, it is predicted that oil-water contact (OWC) of Huhe 16 trap is -1 025 m, which has been confirmed by drilling. Generally, the lateral seal abilities of faults in Beier depression show that seal ability above Nantun Formation is stronger vertically, and that in the southwest Beier depression is stronger in plane.

Key words: fault, lateral sealing ability, SGR, quantitative evaluation method, Beier depression, petroleum gas