Conversion condition analysis for vertical migration along faults and lateral migration along sand bodies of oil and gas:Taking the local structure of Bohai Bay basin as an example
FU Guang
ZHAN Mingwang
Abstract：To study the oil and gas distribution of Cenozoic faulted basin,by comparing the displacement pressure of fault filler and both sides of the sand body,as well as the breaking thickness of mudstone cap rock and the minimum fault thickness of oil and gas,a set of discriminant method for the conversion of vertical migration along faults and lateral migration along sand bodies of oil and gas was established.If the displacement pressure of fault filling material is greater than the pressure on both sides of the sand body,vertical migration of oil and gas along faults transforms to lateral migration along sand bodies,otherwise it cannot be transformed.If the thickness of mudstone caprock is less than the minimum breaking thickness,lateral migration of oil and gas along sand bodies transforms to vertical migration,otherwise it cannot be transformed.The discriminant method was applied to Nanpu No.1 and No.2 structure in Bohai Bay basin and in Es1 of Wen'an slope in the middle of Hebei depression to discriminate whether the oil and gas vertical and lateral migration would switch.The results show that oil and gas in Nanpu No.1 and No.2 structure have experienced a conversion from vertical migration along faults to lateral migration along 34 sand bodies of Dongying formation.9 sand bodies didn't have a conversion from vertical migration along faults to lateral migration.Lateral migration of oil and gas in Es1 conversed to vertical migration along faults of Wen'an slope in the eastern and middle part of western area,but did not happen in the rest parts.The discriminant result coincides with the oil and gas distribution found in Dongying formation of Nanpu No.1 and No.2 structure,Es1 and Dongying formation of Wen'an slope,which indicates that the method is feasible.
Keywords：oil and gasvertical migration along faultslateral migration along sand bodyconversion conditiondiscriminant method
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 336-344 )