Geological Application of Microfossils

Module code: GL3108

Module co-ordinator: Professor Mark Williams

Over billions of years, the tiny microorganisms that are a major component of the Earth's biosphere have left a fossil record of their evolution. These organisms include ostracods, tiny aquatic crustaceans that have withstood the five mass extinction events of the past 500 million years, and which can tolerate waters as acidic as a glass of wine or as warm as a hot bath; single-celled foraminifera, which provide evidence of climate change and the growth of the polar ice sheets in deep time, and which sometimes built 'gigantic' shells over a centimetre in diameter; and microscopic spores and pollen that signal the origins and development of the terrestrial biosphere over 460 million years.

This module covers how these microscopic organisms can be used to signal Earth's changing environment over several millennia, how microfossils are used to reconstruct the path of deep time climate change, and some unique aspects of microfossil analysis (for example, their role in the investigation of archaeological artefacts).

(Image: A tiny arthropod (about 1.3 mm long) from the early Cambrian of southern China, preserved with its body and legs. Microfossils like this one are important for reconstructing animal evolution in deep time.)