Extension de la ceinture équatoriale d’eaux littorales chaudes au cours de l’Éocène moyen, fondée sur la distribution latitudinale des grands Foraminifères en Europe occidentale et en Afrique australe
Gérard Bignot, Charles Pomerol, 2010. "Extension de la ceinture équatoriale d’eaux littorales chaudes au cours de l’Éocène moyen, fondée sur la distribution latitudinale des grands Foraminifères en Europe occidentale et en Afrique australe", Micropalaeontology, Sedimentary Environments and Stratigraphy: a Tribute to Dennis Curry (1912–2001), John E. Whittaker, Malcolm B. Hart
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Larger foraminifera occur today in marine infra-littoral environments whose mean annual temperature (TAM) is at least 22-23 °C, and are situated in a circum-equatorial belt between latitudes 30° North and 30° South. Throughout the Middle Eocene (around 40 Ma), the carbonate platform, which lay along the whole length of the Atlantic front of Europe, supported diverse populations of larger foraminifera as far north as the Paris and Hampshire basins, which at that time were situated at latitude 42° North. Larger foraminifera only disappear around 45° North. During the same period, in the carbonate platform which borders the African and Madagascan shores, larger foraminifera were well diversified as far south as palaeolatitude 35° South, before diminishing and finally disappearing near 45° South. Thus in the Middle Eocene, the equatorial belt of near-surface warm waters lay between parallels 45° North and 45° South, and was therefore somewhat extended compared to the present day. In fact, it covered a distance of 1500 km, North to South. The global latitudinal thermal gradient, as a consequence, was very much reduced (in the order of 15-20 °C), and only contained three main climatic zones: an expanded equatorial belt (TAM > +22/23 °C), flanked by two circumpolar caps with a temperate climate.
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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.