Hydrocarbon Reservoir Prediction Of Huang Long Formation Of Carboniferous In Wan Zhou-BaShanSi Syncline Of East Sichuan Basin

Sichuan Basin is the main production area of large oil and gas fields in southwestern China,and the Upper Carboniferous Huanglong Formation is one of the main oil and gas production zones.In the past,the Carboniferous oil and gas exploration in the Sichuan basin was mainly concentrated in the structural high position,but the Carboniferous in the structural low syncline area was not paid effective attention.In this paper,the Carboniferous Huanglong Formation in Wanzhou-Bashansi Syncline area of Eastern Sichuan is taken as the research object,and the comprehensive prediction of the Carboniferous Huanglong Formation reservoirs in the study area is carried out by using high-resolution seismic processing technology,seismic forward modeling technology,seismic inversion technology and seismic geology technology.The seismic data collected in the study area are of different years,different quality and unclear seismic imaging.High resolution processing technologies such as filtering,frequency raising and denoising are used to process the random noise effectively,overlapping wave groups are separated from each other,the contact relationship between strata is clearer,and the seismic resolution is improved.The Carboniferous strata are affected by denudation.and the lateral variation of strata is fast,the reflection structure is changeable and the characteristics are not obvious.By using forward numerical simulation,the seismic reflection characteristics of Carboniferous strata under different thickness conditions are discussed and summarized by changing the thickness of Carboniferous strata.Based on this,Carboniferous strata are interpreted carefully,and time-depth conversion is carried out with drilling data to form Carboniferous strata thickness distribution map.Seismic inversion technology is the core technology of reservoir prediction.Simulated annealing method can avoid local extremum problem and has high resolution.A global optimization simulated annealing algorithm is used to solve the broadband constrained inversion optimization problem.Based on the simulated annealing inversion method,the wave impedance data volume is calculated.On this basis,the lithology sensitive curve gamma logging curve of the study target area is selected for lithology inversion,and the main development areas of reservoir dolomite are divided.The porosity is inverted by using the wave impedance data volume,combined with the thickness interpretation,lithology inversion and porosity inversion results of the Carboniferous Huanglong Formation.The relative reservoir development areas in the study area are divided.Reservoir prediction and evaluation are carried out by synthesizing seismic forward modeling results,inversion results,reservoir characteristics,reservoir-forming conditions(generation,reservoir,capping,etc.)and main controlling factors of reservoir formation,and favorable target areas are selected.