Tag: oligocene

england geology

Erratic rocks in fields and beaches of the Isle of Wight

 Stephen K Donovan (The Netherlands) The Isle of Wight is a marvellous place for the geologist on holiday, but there must be a suspicion that it has all been done before. When I first visited the island in 1999, my late wife Trina said that, of course, I would want to geologise at some point. She was surprised at my immediate and emphatic reply of ‘no’, until I explained that every square inch of the island was already ‘claimed’ by so many geologists and groups of geologists that I could not possibly get involved without starting a priority war. I was there to relax, not fight. Fig. 1. Outline map of the Isle of Wight, showing the positions of the principal settlements and villages mentioned in the text, and Sites 1-3. Key: CP = Chessell Pottery; EC = East Cowes; OH = Osborne House; 1-3 = collecting sites mentioned in the text. Today, I have a different approach. The family Donovan goes to the Isle for their summer holidays most years and I still go to the island to relax, not fight. But I am now working on a range of projects on the Island that are unlikely to impinge on other peoples’ research, while informing my own interests. These have included identifying borings in fossil wood from the Cretaceous greensands that have been misnamed since the nineteenth century (Donovan and Isted, 2014) and exploring closed railway lines using a geological field guide published a hundred years ago (Donovan, 2015). … Read More

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climate geology URBAN AND HUMAN

Alternative view on climate change

Joe Shimmin (UK) Before you start shouting at your magazine, don’t worry, you’re not going to read that I think climate change isn’t happening or that human beings aren’t contributing to it. However, I am going to try to show that the version of climate change that we are always being shown may not be all that we should be thinking about. If you look at the timescale over which human-influenced climate change has been happening – and compare it with geological time – it is such a tiny period. However, people do not live over geological time periods, so it is natural that we concentrate on the present, with little regard for the past. In fact, with today’s human influenced climate change taking up all of the limelight, anyone would think that climate change was solely a human invention and that before the industrial revolution, the climate had been stable. But this is not the case. Fig. 1. A Map of Europe during the last glacial maximum. Blue areas are covered by ice. Green areas are land. White shows oceans and seas. In the event of a glaciation, could the influx of people migrating from the north be mitigated by the growth of the land masses due to a drop in sea level? Picture credit: Kentynet. A quick glance at Figs. 2 and 3 shows massive changes in average global temperature across the millions of years of geological time. The y axis of the graph shows change in average … Read More

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europe fossils geology palaeontology

Palaeocene lagerstätte in France

Dean Lomax (UK) A Lagerstätte is a sedimentary deposit that exhibits exquisite fossil richness, detail and/or completeness, often preserving fine details, including soft parts, which wouldn’t normally be found as fossils. There are two main types of fossil Lagerstätten: concentration Lagerstätten, which simply consists of large concentrations of fossils found together in deposits such as bone beds; and conservation Lagerstätten, where the defining feature is the preservation of quality rather than the quantity of fossils. A few examples of famous Lagerstätten include the Eocene Green River Formation, which is primarily known from Wyoming, but can also be found in Colorado and Utah. Famous European Lagerstätten include the Solnhofen Formation of Bavaria, Germany. This has produced some spectacularly preserved fossils, including Archaeopteryx, which is considered to be a transitional fossil between dinosaur and bird evolution. Another famous Lagerstätte, situated in central Germany, is the Messel Pit (Grube Messel). This quarry contains Eocene-aged strata and has produced specimens such as Darwinius masillae, identified as a basal primate and described in 2009. Fig. 1. A group searches for fossils in one of the privately owned quarries. (Photo by Dean Lomax.) Geological setting and location Menat is a small village located within the department of Puy-de-Dôme, Auvergne in central France, near the town of Gannat, a town famous for Oligocene and Miocene-aged fossil deposits. The geology of Menat consists of sedimentary rock that includes soft shale layers (including bituminous, pyritious and oil shales) and hard layers consisting of diatomite. The preservation of the fossils … Read More

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