Fractal characteristics of fracture in Zhuangxi buried hill reservoir, Jiyang depression

Key words:  fractal theory  reservoir  fracture  Jiyang depression  Zhuangxi buried hill

Abstract:

Based on fractal theory and the relationship between fracture density of core and fault capacity dimension in Zhuangxi buried hill, the fractures in carbonate reservoir were quantitatively analyzed. Combined with the exploitation situation of oil and gas in study area, the limit of fractal dimension in Zhuangxi buried hill was determined. The favorable regions of the fracture and the oil and gas accumulation were predicted in Zhuangxi buried hill reservoir, Jiyang depression. The results show that the fractal dimension of Tg₁ seismic reflection layer is 1.3174 and correlation coefficient reached 0.99. Capacity dimensional linear regression correlation coefficient of the fracture on sixteen cores of Lower Paleozoic is greater than 0.97. Fractal dimension can be used to compare and to evaluate the development degree and the complexity of fracture in Lower Paleozoic fractured reservoirs. The density of fractures was calculated quantitatively in the area under the Paleozoic fractured reservoirs. The region where the fractal dimension is greater than 1.4 is the most favorable area of fracture and favorable area for oil and gas accumulation. The region where the fractal dimension is 0.8-1.4 is more favorable area of fracture. The region where the fractal dimension is less than 0.8 is the negative area of fracture.