The Fractal Methods of Box-counting and Correlation Dimension Based on Well Log Data

摘要

We use fractal analysis to estimate the dimension of well log curves acquired from Liaohe oil field, China. The box-counting and correlation dimension methods were proposed for predicting the texture of volcanic rocks, which are applied to calculate the fractal dimension of logging curves using neutron logging (CNL), density logging (DEN), acoustic logging (AC), resistivity logging (R_(LLD)) and gamma-ray logging (GR) from 108 wells, 1100 m sections with a total of 8800 logging data. Then we found the corresponding relation between fractal dimension of well logging curves and the texture of volcanic rocks. It was observed that the fractal dimension of CNL, DEN and AC have same value, and the fractal dimension of volcanic lava is lower than the fractal dimension of pyroclastic rock. To validate the accuracy of conclusion, we take X-10 well, 2300-2580 m sections for example, describe the relationship between the fractal dimension and the texture of volcanic rock in certain depth. Compare the predicting result of texture of volcanic rocks with core samples, the accuracy reaches 90%, our studies demonstrated that the fractal dimension of well logging curves will be useful for predicting the texture of volcanic rocks.