Abstract
The specific purpose Monte Carlo code McLDL has been developed to simulate gamma-ray lithodensity log responses. It calculates the energy deposition spectrum in the detector which can be used to generate its pulse-height spectrum. It also has the complete density and/or composition correlated sampling feature. The primary variance reduction method used is combined splitting and biasing through two types of pathways to the detector. McLDL has been benchmarked both experimentally and computationally and should prove useful to those interested in the interpretation or design of gamma-ray lithodensity logs.