Foraminifera from flint meals and ‘rotten’ flints: the choice of an eclectic
H. W. Bailey, C. J. Clayton, 2010. "Foraminifera from flint meals and ‘rotten’ flints: the choice of an eclectic", Micropalaeontology, Sedimentary Environments and Stratigraphy: a Tribute to Dennis Curry (1912–2001), John E. Whittaker, Malcolm B. Hart
Download citation file:
The recovery of well-preserved microfossil remains, both as flint meal faunas and from ‘rotten flints’, intrigued Dennis Curry to such a degree that he set about thoroughly investigating their occurrences, which were otherwise largely overlooked by other micropalaeontologists. His analyses were quantitative and from geographically widespread locations, lending them a significance that is still valid. His results proved that a greater abundance of planktonic foraminif-eral taxa is seen in flint meals when compared with ‘normal’ chalk samples from the same strati-graphic levels and that higher abundances are recorded from the Yorkshire samples when compared with those from southern England. He speculated on the factors causing differential preservation between chalk and flint meal microfaunas, the origins of flint and also on the strati-graphic and palaeogeographic distribution of planktonic foraminifera. Similarly, analysis of Upper Cretaceous foraminiferal associations derived from ‘rotten flints’ obtained from Palaeogene sediments helped him to formulate his ideas on the post-Cretaceous erosion of Upper Cretaceous Chalks around southern England. Curry's 1982 hypothesis that the greater abundance of micro-fauna in flint meals results from selective preservation has proved to be correct. The selective replacement of microfossils, and particularly foraminifera, is the earliest stage of flint formation and predates a phase of large-scale carbonate dissolution and opal-CT lepisphere precipitation and subsequent cementation with interstitial chalcedony. Hence, variably silicified microfossils are preserved in the poorly silicified chalks associated with flint meals and particularly in carious flints, where the preserved fauna is protected from any subsequent dissolution that affected the host sediment.
Figures & Tables
Micropalaeontology, Sedimentary Environments and Stratigraphy: a Tribute to Dennis Curry (1912–2001)
Dennis Curry was a remarkable polymath and philanthropist, leading a double-life as one of the UK's most gifted amateur geologists, whilst at the same time being an extremely successful businessman (as Managing Director of Currys Ltd). This Festschrift, authored by friends and specialists from Britain and France, pays tribute to his often seminal research as well as exhibiting the wide range of his geological interest. It contains 12 chapters and covers several differing aspects of micropalaeontology (pteropods, diatoms and especially foraminifera), Strontium Isotope Stratigraphy, Hampshire Basin stratigraphy and palaeogeography, as well as major contributions on English Channel sedimentology and the great faunal turnover affecting mammals at the Eocene-Oligocene boundary. A scientific appreciation of Dennis Curry, ‘the professional amateur’, with recollections of former colleagues at University College, London (where he was Visiting Professor), together with an assessment of the valuable collections he established and donated to The Natural History Museum, are also included. Copiously illustrated, this book is a must for all geologists.