小面元三维地震勘探技术在西山屯兰矿南五采区的应用

屯兰矿南五采区地形复杂，最大高差达271m，地表大面积为第四系黄土覆盖，激发困难。为探索研究小面元三维地震勘探技术的应用效果。在常规三维地震勘区域内划出1km^2，采用5m×5m小面元进行采集。在地震数据采集过程中，采取了加大激发井深、提高覆盖次数、减小CMP面元网格和加大接收排列等技术措施，做到“四小三高、二中一深、两个等高面”。通过插值、抽线及扩大面元处理。获得2．5m×2．5m×1ms、5m×5m×1ms、5m×10m×1ms、10m×10m×1ms以及不同叠加次数的三维数据体。资料解释工作主要是在5m×5m×1ms、2．5m×2．5m×1ms两个数据体上进行，解释落差大于或等于5m的断层6条，落差3～5m的断层8条；查明长轴直径20～30m的陷落柱4个。30～100m的陷落柱1个，大于100m的陷落柱3个。与相邻区常规三维地震比较，小面元三维地震勘探有利于对小陷落柱、小断层的控制和解释。

Application of Small Surface Element 3D Seismic Prospecting in S5 Winning District,Tunlan Coalmine,Xishan

The S5 winning district of Tunlan coalmine has complicated surface relief; maximum height difference could be 271m as high. Quaternary loess has covered in a great measure, thus a difficult shot condition. To probe into the applicable effect of small surface element 3D seismic prospecting technology, an 1 km2 area has lined out to carry out 5m×5m small surface element acquisition. Technical measures of to increase shothole depth and fold, reduce CMP surface element grid and increase receiving array have adopted, and lived up to ＂4 smaller 3 higher, 2 medium 1 deep and 2 contour planes＂. After interpolating, line extracting and surface element enlarging, obtained 2.5m×2.5m×1ms, 5m×5m×1ms, 5m×10m×1ms, 10m×10m×1ms and different stacking fold 3D data volumes. Data interpretation is mainly carried on 5m×5m×1ms and 2.5m×2.5m×1ms data volumes, interpreted 6 faults with throw ≥5m, 8 fauhs with throw 3-5m; 4 subsided columns with major axis diameter 20-30m, 1 subsided column with major axis 30-100m and 3 〉100m. Compared with neighboring area conventional 3D seismic, the small surface element 3D seismic is in favor of small sized subsided column and minor fault interpretation.