Lithologic Identification And Reservoir Evaluation Of Carboniferous Volcanic Rocks

With the constantly increasing oil and gas demand in the world, volcanic rocks buried hill reservoir as a special type of reservoir is causing widespread concern in the oil exploration workers. Volcanic rocks buried hill reservoir has a typical "low, hidden, difficult" feature, The traditional theory of clastic and carbonate rocks as the main exploration targets is gradually being broken, Its reservoir characterization study at the exploratory stage.In this thesis, the Carboniferous volcanic rocks in the reservoir of ZhongGuai in Northwestern Margin Area as the study, on the basis of existing research results and previous studies in combination, Make full use of existing seismic, drilling and logging data of the area and a variety of analysis and test data, Use the theories and methods of the volcanic rocks, reservoir geology, for the deep research of the characters of volcanic rocks reservoir in lithologic facies, lithology distribution, The main controlling factors of reservoir development, system analysis, The eventual establishment of the volcanic reservoir in the evaluation criteria, a comprehensive evaluation of the work area of volcanic reservoirs.The results achieved through the study are the following:(1) ZhongGuaiTuQi volcanic reservoir develops rocks include andesite, volcanic breccias, tuff, basalt and granite, andesites and tuff is the most widely development class and granite is the local development class. Andesites mainly located in ZhongGuaiTuQi and east ramp region, tuff distributed in rolling topography of ZhongGuaiTuQi outskirt andesites, Volcanic breccia and basalt are mainly located near the fault zone of KeLaMaYi and HongChe, Granite distribution limitations, mainly located in the JinLong5and Guai26wells, the facies of volcanic rocks include the eruption phase, outbreak phase and volcanic-sedimentary。(2) Reservoir space is mainly secondary porosity and cracks, secondary porosity including phenocryst dissolution pores, matrix dissolution pores, grain mold hole amygdala dissolution pores, cracks including structural erosion and weathering cracks, structural fractures is the mainly cracks in the area, which developed high angle and upright cracks, followed by oblique-crossing and low-angle cracks, Fracture strike is North East, North West and the Near east-west; Cracks filled with a higher degree, calcite is the main types of filler, the better effectiveness of cracks is the high-angle unfilled seam.(3) Physical properties of the rservoir are relatively poor, mainly low porosity-low permeability reservoirs, porosity and permeability correlation is poor, The types of reservoir are mainly fractured reservoirs and pore-fracture reservoir.(4) The main impact of factors of volcanic include:reservoir lithology, fractures, weathering crust karstification and fault structure(5) By the weight method to determine the weight coefficients of the lithology, cracks, weathering crust, fracture, Comprehensively evaluate the favorable reservoir distribution.Through the suudy of Lithology and characteristics in Carboniferous volcanic rocks reservoir of ZhongGuai in Northwestern Margin Area, The lithology, distributin of cracks and the influencing factors of Reservoir development, which can be as the reference value for the deep exploration and development study in the later period.