煤田反演的声波测井曲线重构

声波测井作为测井和地震相结合的桥梁,作为测井约束反演的基础和核心,越来越得到广泛应用。在声波测井曲线品质不好或没有声波测井的地区,人们应用Gardner或Faust等经验公式构造声波测井曲线。这些经验公式砂、泥岩层比较适用,而对含煤地层则不适用。因此,本文提出声波测井曲线重构的方法,即密度、电阻率转换速度加权法,将密度、视电阻率等曲线转换成速度曲线再加权求和。该方法在煤田地震反演中应用,提高了反演的置信度。

Sonic Log Reconstruction and its Application to Seismic Inversion in Coal Field

Sonic log was used more and more extensively, as the bridge that we combine seismic with logging, and as basis and core of inversion with well log constraint. In the district where the sonic log curve performs insufficiently or totally cannot be found, people apply empirical formula to construct sonic log curves such as Gardner of Faust formula etc. The empirical formula is fairly suitable to the sand or mudstone stratum,but it is inapplicable to the coal stratum. Therefore, in this paper we describe a new method for reconstructing sonic log curve,which is to weigh velocity for density and apparent resistivity curve. We change the curves such as density and apparent resistivity etc into velocity curve, multiply weight, and derive last velocity curve from their summation. This method is applied in seismic inversion of coalfield, and increases the creditability of inversion result.