鄂尔多斯西缘前陆盆地巨厚黄土地区地震采集技术

鄂尔多斯西缘前陆盆地表层地质地貌极其复杂，有巨厚黄土区、黄土-沙漠区及山前砾石-黄土区，独特的黄土地貌使得地震采集面临着诸多技术难题。根据以往巨厚黄土地区地震采集经验，采用多种方法系统地开展黄土表层结构精细调查，深入研究黄土地球物理特征及激发因素与表层黄土结构之间的关系，优选激发井位和井深，确保了激发效果；采用小道距、三线小线距、高密度空间采样技术，获得了高信噪比、高分辨率地震资料。研究表明，巨厚黄土地区地震采集时应优选激发井位和岩性，合理选择激发井深；坚持多深井组合激发、单井药量不宜过大总药量要大两项基本原则；采用高密度采样技术，提高采集资料的覆盖次数和信噪比。图10表1参15

Seismic acquisition techniques and their application in hill areas with thick loess, western foreland of Ordos Basin

The surface geology and topography of the western foreland of the Ordos Basin are very complicated. There are thick loess, loess-deserts and mountain front hilly gravel-loess. The loess surface structure is systematically investigated using various methods, and the relationships between the loess geophysical characteristics, the shooting factors, and the surface loess structure are studied. Optimum shooting well location and depth are selected to guarantee the shooting results. High resolution and high signal-noise data are gained by using small trace intervals, small line intervals between three lines, and high density space sampling techniques. The following principles should be taken in thick loess areas: optimizing shooting location and lithology, reasonably selecting of shooting well depth; insisting on multiple and deep well combination shooting, with the whole quantity of charge being large while less charge in single wells; improving fold and resolution by high density sampling techniques.