Research On Alluvial Fan Reservoir Architecture Of Well Logging And Seismic Data Combination In Guantao Formation Of Binxian Uplift And Its Surrounding

The alluvial fan-fluvial facies strata of the Neogene Guantao Formation in the Binxian uplift and its surrounding areas of Jiyang depression are characterized by strong heterogeneity。The lateral correlation has strong multiplicity of solutions,and the fine stratigraphic framework division and alluvial fan architecture distribution are not clear.In addition,the uplift topography and stratigraphic unconformity contact relationship lead to the development of strong reflection shielding layer on the seismic profile,which restricts the fine exploration and development.The effect of sand body prediction in the target layer is affected,which makes it difficult to carry out the alluvial fan architecture work.In view of the above problems,this study is based on comprehensive analysis of seismic,core,logging and regional background data,under the guidance of sequence stratigraphy,sedimentology and architecture model,combined with seismic methods.The precise isochronous stratigraphic framework of Guantao Formation is established by combining well and seismic,and the stratigraphic structure style is defined.The strong reflection shielding layer at the bottom of Guantao Formation is suppressed by matching and tracing strong reflection stripping technology.Compared multiple reservoir prediction methods,and the frequency division inversion is selected to characterize the distribution of the target sand body.On the basis of sand body prediction results,the paper analyzes the alluvial fan architecture elements of the target layer Guantao Formation with the idea of "model guidance and multi-dimensional.At the same time,the influence factors of alluvial fan reservoir architecture distribution in Binxian area are analyzed,and the multi-level architecture dissection is completed.The research shows that:(1)The strata of Guantao Formation of the target layer in Binxian area are developed relatively uneven,the thickness of the strata near the uplift is relatively thin,and the thickness of the formation at the periphery away from the uplift is relatively thick,and the overall trend of thinning towards the center is shown;(2)The strong reflection shielding layer caused by granitic gneiss basement at the bottom of Guantao Formation has a great impact on the accuracy of reservoir prediction,by using the method of matching and tracing strong reflection separation,the strong reflection event is effectively weakened,highlight the effective reflection;(3)After suppressing the strong reflection shielding layer,the effect of frequency division inversion is improved;(4)The sand bodies in the study area are distributed in patches along the edge of Binxian uplift,intersected with each other,and the overall shape is skirt belt.Among them,Ng4-3 small layer sand body is the most developed;(5)The Ng4 layer in the study area can identify three alluvial fan facies type.Among them,the braid-flow facies zone is the most developed,and the runoff-flood facies zone is the least developed;The structural elements of Ng4 in the Guantao Formation of the target layer develop four overlapping styles vertically,and developed four splicing relationships laterally;(6)Three factors affecting the architecture distribution in Binxian County were analyzed,they are the environmental and climatic factors surrounding the fan body,the controlling factors of sequence stratigraphy,and the activity of the Binnan fault.The research results have certain reference significance for the construction of fine stratigraphic framework and alluvial fan architecture model of highly heterogeneous areas under strong reflection.It provides reference for subsequent sand body prediction and fine exploration and development of Guantao Formation.