FINE STRUCTURE INTERPRETATION OF 3-D SEISMIC EXPLORATION IN CHANGPING MINE FIELD

The Qinshui Basin of Shanxi province, a residual coal-rich basin, is the largest coal-bed gas fields in China. The Changping Mine, located in the southern part of the Basin, is a favorable area for coal-bed gas accumulation due to structural causes. A structural map of the area is compiled by calibration of wave speed and fine interpretation of horizons, faults, collapse columns and folds on the basis of a 3-D offset data volume. Comparison suggests that the strike and the buried depth of coal measure strata of the 3-D structural description are basically consistent with the 2-D description. In addition, some small folds along the strike are observed in 3-D structural description, and 19 new faults and 24 new collapse columns are discovered. A fault in the northeastern part of the 2-D structural description and a collapse column at the northeast border are found inconsistent with the 3-D structural description. Through the performance mentioned above, a more accurate interpretation of the coal seams is proposed. The accuracy of the 3-D fine structure interpretation is further verified by logging data. and the 3-D structural description fits better the actual situation.