论文部分内容阅读
因为克里金插值方法考虑了样本的空间统计特征而被广泛应用于地层建模。但对于地层尖灭、缺失等不连续地层情况,常用的克里金方法(如普通克里金方法)通常给出较为平滑的地层厚度估计结果,在地层分布边缘的局部范围内与实际情况相差较大。针对不连续地层,提出一种采用指示克里金和普通克里金相结合的地层厚度估计方法。该方法首先采用指示克里金方法估计地层分布范围,然后采用普通克里金方法估计分布范围内的地层厚度,并根据估计标准差来评价地层厚度的不确定性。将提出的方法应用于上海长江隧道的地层建模,通过交叉验证,证明了该方法在地层分布边缘的局部范围内能明显改善地厚度估计结果,标准差降低了15%~18%,得到了比普通克里金和线性插值方法更接近真实情况的地层厚度估计值。
Because Kriging interpolation method takes into account the spatial statistical characteristics of the sample has been widely used in formation modeling. However, for discontinuous strata such as pinch-out and absence of stratigraphy, the commonly used Kriging method (such as ordinary Kriging method) usually gives a smoother estimation result of stratigraphic thickness, which is different from the actual situation in the local scope of stratigraphic distribution margin Larger. Aiming at discontinuous formation, a method of estimating formation thickness using a combination of indicator kriging and ordinary kriging is proposed. In this method, the kriging method is used to estimate the distribution range of stratigraphy. Then, the kriging method is used to estimate the stratigraphic thickness in the distribution range and the stratum thickness uncertainty is evaluated based on the estimated standard deviation. The proposed method is applied to the formation modeling of the Shanghai Yangtze River Tunnel. Cross validation shows that this method can significantly improve the estimation of the thickness of the ground within the local boundary of the stratigraphic distribution, with a standard deviation of 15% ~ 18% Stratigraphic thickness estimates closer to the real than ordinary kriging and linear interpolation methods.