Charcoal recognition, taphonomy and uses in palaeoenvironmental analysis

Abstract

Charcoal, predominantly the product of wildfires, is abundant in many sedimentary rocks deposited in a wide range of environments, from terrestrial to marine. It also occurs in some volcanic rocks. This paper outlines aspects of charcoal formation (both natural and experimental) and briefly considers the taphonomic processes leading to a final assemblage. This is done using examples from recent fires and through experimentation. The ways in which charcoal assemblages are recognized in the field and extraction in the laboratory are also considered. Methods of charcoal identification are presented. The range of charcoalified plant organs that can be found is discussed and a wide range of study methods outlined (including light microscopy, dark field light microscopy, reflectance microscopy, scanning electron microscopy and synchrotron radiation X-ray tomographic microscopy). Emphasis in this paper is on the study of macro- and meso-charcoal (above180 µm). Finally there is a consideration of the broad use of charcoal from plant evolution studies, fire history studies, vegetation studies, anatomical studies, climate and atmospheric studies and the wider importance of charcoal for the Earth and Biological Sciences. Charcoal is information rich but yet is an under-utilized resource.