The Winter Programme Synopses from 2015-2016
Wednesday October 7th 2015
Prof. Mark Williams, University of Leicester
‘Raiders of the last park’ or how humans came to dominate the biosphere
The modern biosphere possesses attributes that are unique in the evolution of life and include: a globally reset pattern of biogeography with many invasive species – even into remote areas of planet Earth; a single species (Homo sapiens) dominating the marine and terrestrial food chains; the human-directed evolution of ecosystems, plants and animals; and the interaction of the biosphere with the technosphere, the global emergent system that includes humans, technological artefacts, and associated social and technological networks. Humans have significantly modified the landscape, for example building megacities that will preserve a fossil record of their materials from above and below ground, including the complex metro systems that exist beneath them. How have these changes progressed through time? What might be the likely geological signature of humans? And, where might the human experiment with the biosphere be leading?
Wednesday October 21st 2015
Dr Sarah Gabbott, Geology Department, University of Leicester
A geological smorgasbord
Experimental taphonomy is undergoing something of a renaissance with the realisation that rotting animals under laboratory conditions provides crucial data to unlock the anatomical interpretation of soft bodied fossils. Moreover, the sequence in which characters are lost through decay is not random (at least in Chordates) but occurs such that the most phylogenetically informative anatomical features decompose the most quickly. I will explore our latest grisly data and what it means.
Sight and stripes in early vertebrates
Being the most primitive living vertebrates hagfish and lamprey are often used as model animals in attempting to reconstruct the sequence of events that took place in the evolution of the vertebrate camera-style eye. However, so far the fossil record has been mute on this controversial subject because fossil eyes from the relevant taxa have been too poorly preserved. I will show remarkable preservation of ultrastructural details of the eyes of Carboniferous hagfish and lampreys that provides us with a deep time perspective on the evolution of vertebrate vision.
Sediment, algae and wind
Within the fine layers of the 440 million year old Soom Shale of South Africa there are spectacularly-preserved soft-bodied fossils. In addition to preserving an ancient ecosystem the Soom Shale is an important archive of climate change. It formed in the aftermath of the Hirnantian glaciation- one of the most dramatic glacial events in Earth history. The Soom Shale comprises unique layers of clusters of large quartz grains bound entirely within fossilized algae. We believe this formed when glacially-derived debris blew into the sea directly, or was blown first across seasonal sea ice, and fertilized the surface waters stimulating plankton and algal blooms. If read correctly, the unique barcode-like archive of the Soom Shale can provide significant insights into the precise course of climate change as major ice-sheets retreat – and a greatly improved understanding of the climate dynamics of Early Palaeozoic icehouse climates.
Wednesday November 4th 2015
Monica T. Price, Head of Earth Collections Oxford University Museum of Natural History
The Corsi Collection of decorative stones: where geology meets the arts
Faustino Corsi was an early 19th century lawyer in Rome who delighted in collecting samples of the different marbles, granites, serpentines and other polished decorative stones used since ancient times in his native city. He was by no means the first to build a substantial collection or to write about ‘marbles’, but his intellectual approach to the study of decorative stone was more pioneering. He intended that his collection should be used as an identification aid, and significantly, he recognised that an arrangement into a petrological order would be most useful. In his published catalogue, he tried to articulate in his descriptions such subtle details as grain- size, texture, lustre, and significant mineral and fossil constituents, as well as the more obvious properties of colour and pattern. While some parts of his geological commentary are satisfyingly accurate, others reflect contemporary mineralogical misunderstandings or represent a curious discrepancy between theory and observation.
Corsi's work brought a geological perspective to decorative stones – an area that had largely been the preserve of artisan stone workers, archaeologists and antiquarians. He helped to give decorative stone collections a rightful place in scientific institutions worldwide. I will be telling you more about Corsi and his collection, and the website www.oum.ox.ac.uk/corsi which allows anyone worldwide to explore this beautiful collection.
Wednesday November 18th 2015
Dr Simon Drake. Birkbeck College
A re-appraisal of the volcanic evolution of the Isle of Skye, N.W. Scotland: hot stuff, big bangs and meteorites
Recently three new phases of Palaeogene silicic volcanism have been established on the Isle of Skye N.W Scotland. Their existence and nature radically change the accepted evolution of the islands Central Complex. We now know that whilst effusive fissure fed basic lavas volumetrically dominated early events, the entire volcanic episode entailed outpourings of silicic pyroclastic density currents that left some deposits similar in nature to those found in large N.W American province such as Snake River. Idaho. A mantle plume which impinged on pre-existing continental crust is generally accepted as being the ‘initiator’ for volcanism on Skye and other parts of the British Palaeogene Igneous Province. We however suggest that the presence of shocked quartz and zircon at the base of the Skye volcanic pile indicates volcanism could have been initiated by an impactor.
Monday November 30th 2015
Parent Body, Leicester Literary & Philosophical Society
Tom Sharpe University of Cardiff, and Lyme Regis Museum
Mr Smith’s remarkable maps
The production of William Smith’s famous 1815 geological map, A Delineation of the Strata of England and Wales, with part of Scotland …, was far from straightforward. Encouraged by his friends in Bath, Benjamin Richardson (1758-1832) and Joseph Townsend (1739-1816), to publish his discoveries on the sequence of strata and their contained fossils, Smith issued a prospectus for a work on the strata of England and Wales in 1801. But John Debrett (1753-1822), who had agreed to publish it, was declared bankrupt and it was over ten years before the cartographer John Cary (1755-1835) offered to publish Smith’s map. The map and its accompanying Memoir were eventually published in early September 1815, and its distribution began to the 410 subscribers listed in the Memoir. However, few had paid in advance, some refused to take their copies, and at least ten had died during the map’s ten-year long gestation. Those who did purchase a copy were not all sold the same map; in addition to complaining to Cary about the variable quality of some of the colouring, Smith continually revised and altered the map, which must have been a source of irritation to Cary. Despite this, Cary continued to support Smith’s publishing of his cross sections, reduced map of England and Wales, and county maps into the 1820s.
Although publication of the Geological Society’s map in 1820 must have impacted upon the sales of Smith’s map, sheets of the map were still being printed in the 1820s and several maps were produced in the late 1830s, just a few years before Smith’s death in 1839.
Wednesday December 2nd 2015
Dr Michael Simms National Museums Northern Ireland
From Here to Eternity: The extraordinary 4.5 Billion year story of the Barwell meteorite
Wednesday January 13th 2016
Dr Albert Benghiat National Stone Centre, and ViceChair Section C - Geology LLPS
Doctors and Geology
This talk will start by examining the geological contributions made by eminent physicians and surgeons of the past and go on to explore the possible similarities between medicine and geology.
Wednesday January 13th 2016
Dr Marc K. Reichow Dept Geology University of Leicester
Explosive super-eruptions: The story of the Yellowstone volcanic track
Super-eruptions are, after meteorite impacts, the most catastrophic events on Earth and are defined as massive, caldera-forming explosive eruptions with volumes exceeding 450 km3. Whilst it is well-known that Yellowstone has erupted catastrophically it is less widely appreciated that this was the last, and probably the smallest, of a series of very large explosive eruptions. The Yellowstone – Snake River Plain volcanic province in the western United States has produced some of the most voluminous eruptions on Earth (~2000 km3) over 16 million years (Miocene – present). Volcanism along the hotspot track is exceptionally hot (~1000°C) and distinctive in style, which produced giant, searing-hot density currents that deposited extensive rheomorphic glassy ignimbrites. However, our knowledge about these older eruptions, such as how frequently they appeared and how the magmatic system evolved, is unfortunately limited as the volcanic rocks often closely resemble one another in the field and have similar chemistries.
This presentation focuses on the determination of the size and frequency of the older, Mid-Miocene volcanic record. The identification and correlation of individual layers can be achieved by combining tools including: field logging and sampling coupled with characterization of the whole-rock and mineral chemistries, high-precision 40Ar/39Ar dating and detailed palaeomagnetic characterisation of polarities and secular variations. This multidisciplinary approach provides robust ‘fingerprints’ that enable individual eruptions to be distinguished, and facilitates robust correlations between sites spaced >100 km apart. These provide a much-needed foundation, not least in quantifying the likely eruptive volumes of an individual event, to start to assess the environmental impact of these remarkable events.
Wednesday February 24th 2016
Dr Marcello Ruta School of Life Sciences, University of Lincoln
Models of morphological evolution during vertebrate terrestrialisation
This talk summarises current research developments in the field of early limbed vertebrate evolution. The last three decades have witnessed an astounding proliferation of early tetrapod studies, spurred by novel fossil finds, reinterpretation of existing data, and the widespread use of comparative methods in macroevolutionary analysis. In the first part of the talk, we shall review existing debates, particularly conflict in early tetrapod phylogenies and possible solutions. In the second part, we shall focus on models of skeletal changes in the appendicular skeleton across the fish-tetrapod transition. In the final part, we will look in detail at the evolution of the humerus, as this bone underwent some of the most profound re-patterning of any skeletal element. The final part of the talk will serve to illustrate the potential of comparative methods in the study of evolutionary patterns and processes, particularly analyses of evolutionary rates, models of diversification, and morphological disparity.
Wednesday March 9th 2016
Prof John Bridges Department of Physics and Astronomy, University of Leicester
The Curiosity Rover has revealed an ancient lake on Mars and changed our view of how that planet may have been habitable 4 billion years ago. Our view of Mars as having a purely basaltic igneous crust has also changed as we find evidence for more silica-rich igneous rocks. We are following up our discoveries on MSL (Mars Science Laboratory) by planning a European Rover – ExoMars. The University of Leicester is heavily involved in this Mars exploration.
Saturday March 12th 2016
Planet of the Apes
Wednesday March 23rd 2016
Dr Mark Evans New Walk Museum, Leicester
The Mesozoic Marine Reptile Renaissance: Part 2