The Effect of Seasonal Factors on Geological Interpretation of MSS Data

Temporal variations are considered to be important factors in their effects on remotely sensed image data and discrimination analysis of the images as a basis for geologic interpretation. Some systematic temporal factors may be corrected by instrument adjustment but random and stochastic factors are not necessarily systematic. However, statistical methods can be used to determine the effect of the stochastic temporal factors. In this study, 29 MSS subscenes from northern Lincoln County, Nevada images were obtained and nine different lithologies were sampled. Two linear statistical models related to the stable background and seasonal factors were constructed and tested. The results suggest that (1) the band brightness values resulting from different lithologies are statistically different; (2) the seasonal effects do exist in a statistical sense; (3) the seasonal factors are such that the bands show higher values in summer and fall, but lower in winter and spring; (4) the seasonal effects are consistent within the four MSS bands for any given lithology area; and (5) the seasonal factors are consistent for different types of lithology within any given MSS band. These results provide statistical support for lithological classification using remotely sensed data.