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This study compares high resolution forward models of natural gamma-ray background with measured by high resolution aerial gamma-ray surveys. The ability to predict variations in background radiation levels should prove useful for those engaged in measuring anthropogenic tributions to background radiation for the purpose of emergency response and homeland security erations. The forward models are based on geologic maps and remote sensing multi-spectral combined with two different sources of data: 1) bedrock geochemical data (uranium, potassium thorium concentrations) collected from national databases, the scientific literature and private panies, and 2) the low spatial resolution NURE (National Uranium Resource Evaluation) aerial gamma survey. The study area near Cameron, Arizona, is located in an arid region with minimal vegetation due to the presence of abandoned uranium mines, was the subject of a previous high resolution gamma ray survey. We found that, in general, geologic map units form a good basis for predicting the distribution of the gamma-ray background. Predictions of background gamma-radiation levels based bedrock geochemical analyses were not as successful as those based on the NURE aerial survey sorted by geologic unit. The less successful result of the bedrock geochemical model is most likely due a number of factors including the need to take into account the evolution of soil geochemistry chemical weathering and the influence of aeolian addition. Refinements to the forward models made using ASTER visualizations to create subunits of similar exposure rate within the Chinle which contains multiple lithologies and by grouping alluvial units by drainage basin rather than age. (C) 2016 The Authors. Published by Elsevier Ltd.