Research On The Main Controlling Factors Of Hydrocarbon Accumulation In Local Tectonic Belt Of Liaoxi Bulge, Liaodong Bay Area

The tectonic zone of Liaodong Bay depression oil and gas enrichment zone is an important position in Bohai oilfield exploration.However,there is a great difference in the degree of oil and gas accumulation in different parts of the same structure or in the same structure,so it is necessary to systematically analyze the main controlling factors of hydrocarbon accumulation and reveal the law of oil and gas accumulation.In this paper,based on the core,logging and seismic data to conduct a comprehensive research on JZ20-2/2N?JZ25-1/1S and other typical oil-bearing structure,based on the distribution characteristics of clear oil and gas,a comprehensive analysis of the basic conditions and factors of oil and gas reservoir,reveals the main controlling factors of reservoir of oil and gas,clear the strike slip control system under the background of aggregation of fracture migration of oil and gas migration,and establish the research area accumulation model.The results show that the study area has a good oil source condition,reservoir cap combination and preservation conditions,and the location of the hydrocarbon accumulation and the possibility of hydrocarbon accumulation can be determined by the transport conditions dominated by faults.Based on this understanding,the first to focus on fracture,and based on the nature of the fracture tectonic belt,the fault is divided into source control faults,reservoir controlling faults and fault sealing of regulation;and then control the source fault to open and reservoir fault respectively for quantitative evaluation,through the research angle,active fault zone and the fault sealing index on the relationship between oil and gas accumulation in the study area between the structure,clear the fault transporting control effect on hydrocarbon gas.Research shows that oil and gas in the tectonic belt are mostly greater than 34 degrees and the faults in the fault dip termination?Ng?Nm?the position of the fault opening is conducive to the vertical migration of oil and gas;near the study area oil and gas bearing structure of fault sealing index,minimum at around 9,the fault enclosed is conducive to the preservation of oil and gas,the result shows that the fracture in the migration and preservation of oil and gas transporting aggregation plays a major role.There are 2 types of oil and gas accumulation models in the study area,which are the single source hydrocarbon migration and accumulation pattern,and the dual source hydrocarbon fault sand complex reservoir formation model.The former is mainly from the oil and gas in the north and middle of Liaoxi sub sag Es₃ section in Dongying at the end of the formation,the main fault group migrated to Es₂ section or three sections of sand traps,and rely on traps controlling reservoir fault block reservoir;the latter is the source of oil and gas from Liaoxi and Liaozhong two depressions in Dongying group or at the end of Ng formation and Nm period,consists of two main faults and Liaozhong sag sand bodies are configured to form complex transport system,two sections of the Ed₂ or Shahejie Formation Group trap in the accumulation of oil and gas migration to the.