Alteration form

Compilation of terms that described geometry (i.e. the shape, distribution and configuration) of alteration in rocks and minerals as observed at the macro-, meso- and microscopic scale, and applying to the specific area of observation. Alteration in this context is defined as a modification of the original lithology caused by meteoric, connate, metamorphic, or magmatic-derived fluids, excluding the weathering environment, mineralization and direct magmatic or metamorphic processes. Definitions are largely taken from Pirajno (2009) and the Glossary of geology (Neuendorf et al., 2011).