D. Zhou 1985 <p>Conventional analyses of exploration geochemical data assume that the background is a constant or slowly changing value, equivalent to a plane or a smoothly curved surface. However, it is better to regard the geochemical background as a rugged surface, varying with changes in geology and environment. This rugged surface can be estimated from observed geological, geochemical and environmental properties by using multivariate statistics.</p> application/pdf 10.1016/0375-6742(85)90046-9 en Elsevier Adjustment of geochemical background by robust multivariate statistics article