自然伽马拟声波曲线构建技术探讨

Latest Discussion on Natural Gamma-ray Pseudo-acoustic Curve Construction Technology

声波测井曲线在地震反演中起着约束和控制模型反演的作用,当其不能反映地层岩性变化时,通常会将现有的非声波测井曲线按照一定的经验公式或统计方法来重构新的声波曲线。但是,这些拟声波曲线构建技术并没有考虑到地层岩石孔隙及孔隙中流体的影响。在考虑到岩石孔隙和孔隙中流体的情况下,拟声波曲线构建技术可以先利用岩石基质的声波速度与自然伽马之间的关系来重构具有声波量纲的新曲线,然后结合原声波曲线中能够反映背景速度的低频信息,构建出新的声波曲线。该方法在鄂尔多斯盆地镇泾地区取得了不错的应用效果。

The acoustic logging curve plays a role of constraint and control model in seismic inversion, when it can not reflect strata lith-ological changes, commonly will reconstruct new acoustic curves through existed non acoustic logging curve with certain empirical for-mulae or statistical approaches. But these pseudo-acoustic curve construction technologies have not considering the impacts from rock pores and pore fluid. Thus the authors have reconstructed new pseudo-acoustic curves with acoustic dimension using relations between acoustic wave velocity in rock mass and natural gamma-ray considering the impacts. Then combined with the low frequency informa-tion in original acoustic curves reflecting the strata background velocity to reconstruct new acoustic curves. Good results have been made in Zhenjing area, Ordos Basin through the method.