The School of Geography, Earth and Environmental Sciences organises a regular series of research seminars throughout the academic year to which everyone is welcome to attend. Speakers - both external and internal to the University - will talk on topics related to all aspects of Earth Sciences.
Today's speaker is Professor Steve Rowland from the School of Geography, Earth and Environmental Sciences.
In the 1960s, the Nobel Laureate Melvin Calvin and the late Geoffrey Eglinton FRS, proposed the concept of a ‘chemical fossil’, whereby organic chemicals of biological origin are conceived to be preserved, albeit in an altered state, as recognisable fossil skeletons of the original molecules, even after millions of years. In perhaps its simplest form, this can be considered as ‘A changes to B’. The concept has proved useful in oil prospecting, oil pollution studies and in many other areas of Earth- and even extra-terrestrial sciences.
However, opportunities to really test the simple ‘A to B’ idea remain elusive. Laboratory simulations are necessarily time limited compared with geological events and attempts to replace time with heat (i.e. to speed up the chemical reactions leading from A to B) have often proved problematic: kinetic products often replace thermodynamic ones.
In our studies of modern biological samples we have made an up-to-date description of a natural material which unusually, perhaps uniquely, comprises almost entirely one substance (‘A’). Recently, physical petrified fossils of the same material have been reported in Pleistocene deposits in central Italy (Gelasianto Calabrian, 1.95-1.55 Ma). Identifications of these fossils have partly relied on the principle of Uniformitarianism with morphological comparisons made with modern material.
Using the same principle, we now wish to compare the chemistry of the modern material (principally chemical ‘A) with that of the diagenetically altered, fossilised material from Italy (is chemical fossil ‘B’ really produced?).
The seminar will outline our initial findings and is a ‘work in progress’.