Fluid inclusion petrography

A procedure of fluid inclusion studies is proposed with emphasis on the cri teria of selecting fluid inclusions for detailed (microthermometry and spec troscopic) analysis. An overview of descriptive and genetic classifications of fluid inclusions in single crystals and in massive rocks is given with the intention of further differentiating the commonly used terms 'primary' and 'secondary' fluid inclusions. Some principles of fluid inclusion modifi cation are explained. Cathodoluminescence (CL) studies of quartz with the o ptical high-power CL-microscope and the electron microprobe provided with a CL detector are an important help in 'fluid petrography'. CL textures are subdivided in primary, growth textures and a wide variety of secondary micr otextures, which are in part induced by fluid inclusions. The latter is gro uped in textures indicative of local lower crystal order (increasing defect structures) and microtextures indicative of local quartz healing (reductio n of the defect structures). Microtextures showing the genetic relationship between fluid inclusions and the host mineral provide information about th e possible post-entrapment changes of fluid inclusions and therewith testif y their geological relevance. (C) 2001 Elsevier Science B.V. All rights res erved.