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Science News

171 Posts authored by: C Lowry
2

LIFE SCIENCES DEPARTMENT SEMINAR

 

British Butterfly.jpg

 

 

 

Using the NHM collections to track the long-term seasonal response of British butterflies to climate change

 

Steve Brooks

Department of Life Sciences, NHM

 

Wednesday 29 January 11:00

Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)

 

 

Changes in the emergence dates of British butterflies have been documented from observational monitoring data which mostly date from the 1970s. Few data, however, are currently available to extend the baseline to the period before the onset of rapid climate change. An important, but neglected, source of information is available in the NHM collections, which can extend this record to the mid-19th century. Our results show that British butterfly collection data reflect phenological responses to temperature. First collection dates of museum specimens advance during warm years and retreat during cold years. Rates of change, however, appear to be slowing in some species, when compared to recent observational data, suggesting some species may be approaching the limits of phenological advancement. Steve Brooks will discuss the potential  of the NHM collections to study the response of animals and plants to recent climate change.

 

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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NEXT EARTH SCIENCES DEPARTMENT SEMINAR

Thermopolis archaeopteryx.jpg

False colour image of the Thermopolis Archaeopteryx.

 

 

Synchrotron-based imaging of zoological and paleontological samples

 

 

Dr Phillip Lars Manning

University of Manchester

 

28th January- 4.00 pm

Earth Sciences Seminar Room
(Basement, WEB 05, the previous Mineralogy Seminar Room)

 

Biomolecules have been identified within living organisms that utilise metals to help mediate or catalyse chemical transformations of organic molecules and/or perform key biological functions e.g., iron in hemoglobin and magnesium in chlorophyll. Trace metals such as copper, zinc and nickel are also essential for routine metabolic functions, performing specific roles dependent on the tissue-type in which they are occur. Therefore, the ability to resolve elemental inventories and their distribution within fossil organisms might provide valuable information pertaining to the biology, function and evolution of a species. However, in order for original biochemistry to be resolved, it must be clearly shown that the observed fossil chemistry has not been derived through geologic/taphonomic processes and that the trace elements are detectable. Commercially available techniques (such as scanning electron microscopy and electron microprobe) lack the ability to chemically image large areas and/or lack the sensitivity required to investigate the trace metal chemistry preserved in fossils. Given the dilute concentrations of such trace-elements in biological tissues, the only reliable way to spatially resolve such inventories is through the application of synchrotron-based elemental imaging techniques. Synchrotron Rapid Scanning X-Ray Fluorescence (SRS-XRF) is a uniquely optimized method that can simultaneously detect elements in trace amounts, accommodate sizeable specimens (up to 1m2) and scan large surface areas in short time periods (~30 s/cm2) at high resolution (~2-100 microns). Complementary X-Ray Absorption spectroscopy (XAS) can also indentify the oxidation state of elements within a fossil and help determine whether they are organically derived. A series of unique fossil samples have already been mapped using SRS-XRF, including a 50 mya reptile (cf.  Bahndwivici ammoskius), 120 mya bird (Confuciusornis sanctus) and a 150 mya bird (Archaeopteryx). Results from both SRS-XRF and XAS clearly show endogenous bioaccumulated trace-metal chemistry can be preserved in fossils after tens of millions of years. The results provide a unique insight into the preserved biochemistry of these extinct organisms.

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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EARTH SCIENCES DEPARTMENT SEMINAR

 

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(Image from Wikipedia)

 

 

The Vredefort impact structure, South Africa: witness of a planetary catastrophe, gold deposit and world heritage

 

 

Uwe Reimold

Natural History Museum, Berlin


Thursday 23rd January - 4.00 pm
EARTH SCIENCES SEMINAR ROOM

 

The Vredefort impact structure in South Africa is, at some 250 km diameter and 2.02 Ga age, the oldest and largest currently known impact structure on Earth. It encompasses the entire Witwatersrand Basin of great economic geological significance. Because of the great geological age of this impact and the complex multi-stage metamorphic history of the target terrane the recognition of evidence for impact has long been controversial. Shock microdeformation and the genesis of massive pseudotachylitic breccias and enigmatic impact melt rock deposits
will be discussed, as well as the more recent history of Vredefort as a World Heritage Area.

 

 

    

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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LIFE SCIENCES DEPARTMENT SEMINAR

 

NHM Expedition to Sabah, Borneo: Report from the Freshwater Team

 

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Mary Spencer Jones, David Bass, Hanna Hartikainen, Beth Okamura

Department of Life Sciences, NHM

 

Wednesday 22 of January 11:00

Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)

 

Borneo contains some of the oldest rainforest in the world and is characterised by exceptionally high biodiversity being the centre of evolution and radiation of many species of plants and animals endemic to the region. Endemism in freshwater organisms has been particularly demonstrated for fishes, amphibians and some aquatic invertebrates (especially insects), but the diversity of aquatic taxa is poorly understood relative to that of the terrestrial flora and fauna. An even more incomplete understanding characterises what is known of the diversity of parasitic groups in this region and most particularly of those groups that are poorly known overall. The aim of the NHM Sabah Expedition Freshwater Team was to undertake a combination of environmental and targeted sampling to explore the diversity of parasitic groups across a range of sites and habitats. A key component of our work involved adopting environmental sampling to significantly improve on discovery rates of novel endoparasitic lineages and thereby avoid the necessity of finding parasites within host organisms. A second objective was to gain better understanding of the diversity of freshwater bryozoans (Phylum Bryozoa, Class Phylactolaemata) and their myxozoan parasites. We will provide a summary of our activities and results thereby demonstrating how our programme of work is revealing novel biodiversity of aquatic life.


 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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LIFE SCIENCES DEPARMENT SEMINAR

 

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Unappreciated Invertebrates Causing Engineering Nightmares

 

Timothy Wood

Senior Scientist, Bryo Technologies (USA)

 

 

Friday 17 of January 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)


In the 21st Century it is somewhat astonishing to find that biofouling invertebrates routinely shut down power plants, disrupt water supplies, and create other kinds of expensive havoc. While biofouling is generally well managed on ships at sea, in fresh waters it seems to take everyone by surprise. This is despite the fact that incidents of freshwater biofouling are increasing in frequency and severity, due mostly to eutrophication and misguided infrastructure design. Most people are unaware of these problems, industry is oblivious, and engineers are clueless. The cost of cleaning, repairing, or replacing damaged structures is staggering, not to mention the loss in productivity.  Solutions to these problems are usually not complicated nor very expensive, but implementation faces a wide range of institutional hurdles.

 

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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COLLECTION MANAGEMENT SEMINAR

 

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What?
Microscopy and Imaging at the NHM in the 21st Century – how state of the art instrumentation can be used to image and analyse irreplaceable Natural History and Cultural Heritage specimens.

 

When?
Thursday 23rd January 2014, 2.30pm-4.00pm

 

Where?
Flett Lecture Theatre, NHM, South Kensington

 

Who? Speaker: 
Alex Ball, EM Unit manager, Science Facilities NHM.

 

What’s it about?
Microscopy and Imaging is a rapidly evolving discipline and the Museum’s Imaging and Analysis Centre is very much at the forefront of the practical technology for Natural Sciences and Cultural Heritage research. This talk is an attempt to give you both a roundup of the facilities available at the NHM and also to demonstrate some of the ways they have been used at the Museum and to compare them to either “state of the art” applications, or to some of the more eye-catching, media friendly research that has been performed recently.
As a researcher with a background in microscopy, 3D reconstruction and analysis and now over 20 years’ practical experience in electron microscopy applications, I travel regularly to international microscopy conferences and talk frequently with lab managers from other institutions. Staff at the Museum are in a privileged position; not only do they have access to some of the world’s finest natural history collections and libraries, but this is backed up by Science Facilities that are literally world class and free at the point of use (at least for microscopy and analysis). I would like to use this talk to inspire our users to be inventive, to look beyond what is current in their own fields and try to see what might be applied from other fields to their own research.

 

Who should come?
The seminar is open to all interested members of the museum, particularly

 

Science Group: All senior departmental managers & collection management staff.
Public Engagement Group:  Any staff who work with and use collections or manage staff who work with collections.

 

We also welcome colleagues from other institutions who would find the seminar of interest. There is no booking fee and only large parties need to notify the organiser for catering purposes.


Tea and coffee will be available in the lobby area after the talk.

 

Suggestions for seminar speakers are always most welcome. Please contact the organiser Clare Valentine (c.valentine@nhm.ac.uk)

 

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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EARTH SCIENCES DEPARTMENT SEMINAR

Norilsk.jpg

(Image from Wikipedia)

 

 

Unique PGE-Cu-Ni Noril’sk deposits: geology and origin

 

Nadezhda Krivolutskaya

Vernadsky Institute of Geochemistry and Analytical Chemistry RAS, Moscow, Russia

 

 

Tuesday 14th January - 4.00 pm

EARTH SCIENCES SEMINAR ROOM

 

Thanks to their uniqueness in the extensive class of magmatic Pt-Cu-Ni deposits (their setting in the flood-basalt province, young age, and the vast thickness of the ores related to the relatively thin intrusive bodies), the Norilsk ore-bearing massifs continue to attract keen interest of researchers during more than five decades. The paramount impact of the discovery of the Talnakh deposits on the world's economy still puts forth the problems of the genesis of such ores. Solving these problems will facilitate in optimizing exploration for such unique ores.

Although the Norilsk deposits have been studied for a long time, several issues of their genesis remain obscure until nowadays. A principally important problem is the mechanisms that concentrated metals in the uniquely large deposits. Several hypotheses were suggested to explain this phenomenon. Some researchers explained the unusual structure of the deposits by their origin from unusual ore-bearing magmas, others argued that the deposits were produced by tholeiitic melts during their long-lasting ascent to the surface. Practically all of the genetic models attach much importance to the assimilation of rocks, first of all, anhydrite, which provided sulfur for the system.

Our study of geological relations between basalts and intrusions in the Norilsk Complex and on their major- and trace-element compositions (6 - 7 wt % MgO in the volcanic rocks and 10 - 12 in the intrusions, relatively low Ti concentrations and La/Yb ratios in rocks of the Norilsk Complex) and isotopic composition (first of all, sulfur isotopic composition δ34S from +1 - +5 to +18‰ for the basalts and intrusions, respectively), the conclusion was drawn that the ore-bearing intrusions have no comagmatic volcanic rocks and were produced by a separate magmatic pulse in post-Nadezhdinsky time. There is much less evidence that the magmas of the Norilsk Complex were emplaced in post-Morongovskoe time and, perhaps, even after the whole volcanic pile was formed (Malich et al., 2010; Ivanov, 2011).

We were the first to widely apply a new approach to estimating the composition of the parental melt of a given rock based on data on melt inclusions in the early liquidus phases (olivine and pyroxene). In particular, we have demonstrated that the ore-bearing massifs were produced by highly magnesian (up to 8 wt % MgO) melts that contained olivine and plagioclase phenocrysts and had crustal characteristics: negative Ta-Nb and positive Pb anomalies and did not contain elevated concentrations of base metals. The melt contained 0.5-0.7 wt % H2O with low concentrations of Cl (0.2 wt %) and CO2 and its characteristics were close to those of lower crustal rocks (εNd = 0 ± 1.5; 87Sr/86Sr = 0.706 ± 0.1) that are are reasonable suitable candidates for the source of the Norilsk parental magmas. The possibility of melting is uncertain.

The two-stage scenario for the genesis of the sulfides seems to offer a more efficient mechanism for metal concentrating than a single-stage process.

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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Not so boring Urticaceae? A framework for the study of over 2,000 species of tiny flowered weeds

 

Alex Monro

Department of Life Sciences, Natural History Museum and Royal Botanic Gardens, Kew

 

Wednesday 11 December 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)


The Urticaceae comprise ca 2,500 species in ca 50 genera. The family was last monographed by Hugh Algernon Weddell in 1856 whose beautifully detailed illustrations still provide the most informative images for this families tiny flowers. I have been studying the family for ca 15 years and in collaboration with Zeng-Yuan Wu we have generated a phylogenetic tree that once will  provide a context for exploring the evolution of these uncharismatic but fascinating plants. I will provide a summary of some of the most promising lines of research as they appear to me.

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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“Across the disciplines” - a student’s perspective on the Marie Curie Initial Training network INTERCROSSING: Introduction to a natural hybrid zone between bluebells species in northern Spain


Jeannine Marquardt

Department of Life Sciences, NHM

 

Wednesday 4 of December 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)

 

This presentation will be split in two parts: (1) I will introduce the Marie Curie ITN INTERCROSSING. The principal strategic objective of INTERCROSSING is the cultivation of a new type of early stage researcher (ESR) to deal with challenges of exploiting the latest Next Generation Sequencing (NGS) technologies. The consortium behind INTERCROSSING are all using NGS technologies, but have found the recruitment of appropriate Early Stage Researchers (ESRs) a major obstacle to build on their innovations. A combination of industrial and academic partners deliver training courses equipping the ESRs to traverse the barriers between these disciplines. Taught courses will provide practical experience of NGS data acquisition, computational methods, model-based statistical inference and population genetics. The NHM - the only charity partner - will deliver training in citizen science and public communication. My PhD project within the ITN (2), one of the few actually using data of non-model organisms, is about studying introgression between Hyacinthoides non-scripta (the British bluebell) and H. hispanica in the natural environment in northern Spain. The analysis of hybrid zones provides a window into speciation from which we can learn about processes that drive species divergence. Especially using genome wide markers generated with NGS technology we have the potential to gain lots of information about the species’ evolutionary history.  I will focus on early results from fieldwork and preliminary analyses of the transcriptome.

 

 

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(Image from Perm State University Web pages)

 

 

Botanical Garden of the Perm State University, Russia: its history, living collections and research

 

Sergei Shumikhin

Perm State University, Russia

 

Wednesday 4 of December 11:30
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)


The oldest in the Urals botanical garden of the Perm University (Perm Botanical Garden) was founded in 1922 by Professor Alexander Genkel, a prominent Russian algologist famous for his work in the Arctic Ocean. In the past, several renowned Russian scientists, including physiologist Dmitry Sabinin and geobotanist Vladimir Baranov were among the Directors of the Perm Botanical Garden. Now it is a large scientific, educational and cultural centre of the Western Ural with the ex situ collections totalling over 6,500 taxa.  One of the main activities of the Botanical Garden is studying and preservation of biodiversity of the local flora. This talk presents the history of the Perm Botanical Garden, its living collections and main research activities, including introduction and re-introduction of Red List species.

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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LIFE SCIENCES DEPARTMENT SEMINAR

 

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Bone-eating worms and wood-eating bivalves: characterising the ecology of deep-sea organic falls from multiple ocean basins

 

Diva Amon

Department of Life Sciences, NHM and University of Southampton

 

 

Wednesday 27 of November 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)


Large organic inputs to the deep seafloor such as the remains of whales or pieces of wood are termed ‘organic-falls’ and are important sources of food, shelter and hard substrate in the deep sea. Despite over 30 years of research on these habitats, we still have only a basic understanding of their taxonomic composition and for some ocean basins, no natural or experimental studies have ever been conducted. The degree of connectivity between these isolated habitats, as well as how quickly organic matter is remineralised by specialist organic-fall fauna, such as bone-eating Osedax worms and wood-eating Xylophaga molluscs, are poorly known. My PhD research has tried to shed light on these topics resulting in the last three years spent undertaking some extraordinary tasks in a variety of locations: collecting whale bones and bone-eating worms from the Antarctic deep seafloor, cutting bones out of beached whales in Kent, sinking wood and whale bones on the Southwest Indian Ridge, diving to 2500 metres in a Japanese submersible, observing what happens when tiger sharks and whale bones meet in the Bahamas, and haggling over pig carcasses with a Jamaican butcher. All in the name of science! Today I will reminisce on a few of these adventures, as well as present results from the penultimate chapter of my thesis: Ecosystem function of the wood-boring genus, Xylophaga (Pholadidae, Bivalvia) revealed by X-ray micro-computed tomography. Wood deployments from two seamounts on the Southwest Indian Ridge were investigated in detail to examine the nature of intact Xylophaga borings, the comparative abundances and population size structures of the species, their rates of growth and their consumption rates of wood. Two more sets of samples from the Mid-Cayman Spreading Centre and the Tongue of the Ocean, Bahamas were also scanned. The wood at each deployment site was colonised by a different species of Xylophaga. This novel analysis has shown that an individual Xylophaga can bore between 0.235 and 0.606 cm3 of wood per year depending on the species, emphasising the importance of the genus Xylophaga with regard to wood remineralisation in the deep sea and its role as an ecosystem engineer.

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

 

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Presentation of PhD results: impact on visitors of meeting scientists in Nature Live

 

Amy Seakins

Collaborative PhD between the Natural History Museum and King’s College London

Thursday 5 December
DC Seminar Room (underneath the Attenborough Studio) 10.00-11.00

 

This thesis explores the impacts of meeting research scientists on visitors to the Natural History Museum, London, from the visitors’ perspective. Firstly, the study aims to investigate whether meeting a scientist changes visitors’ identification of scientists, their perceptions of ‘who scientists are’ and what scientists are like, perhaps challenging previously encountered stereotypes of scientists. Secondly, the study looks at visitors’ identification with scientists, whether visitors become more interested in the life and work of the scientist, seeing science as personally relevant, and whether visitors make connections to the scientist. Through researching the impacts of interactions between visitors and scientists, this thesis adds to the literature aiming to increase science literacy and engagement, contributing to knowledge of how individuals can become more active, confident and interested in science as a part of their everyday lives.

 

Amy is about to submit her thesis so come and discuss her findings with her. They are of value to those who plan public engagement activities as well as those from Science who take part in education programmes and interact with visitors.

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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How to make a tapeworm

 

Pete Olson

The Natural History Museum, Dept. of Life Sciences, Div. of Parasites & Vectors

 

Wednesday 20 November 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)


The evolution of parasitic flatworms represented a major departure from the free-living platyhelminth form, with each group evolving fundamentally different key adaptations toward increased fecundity (i.e. extreme r-selection). Such radical departures in morphology make homology assessment difficult if not impossible and hence we are working to elucidate the molecular signals that underpin their morphological evolution.

 

Using the beetle/rodent tapeworm Hymenolepis microstoma as a laboratory model of a strobilate (i.e. segmented) tapeworm, we now have not only a full catalog of its genes, but also transcriptome (i.e. expressed gene) samples from different regions of the body and ontogenetic stages. These genome-wide transcriptome profiles provide both qualitative and quantitative data on gene expression within a given sample, and through comparison we can thus identify which genes are up- or down-regulated throughout their complex life cycle. Among these we have selected the comparatively small number (~50) of 'developmental genes' (i.e. signalling and transcription factors) and have begun to survey their spatial expression patterns through whole-mount in situ hybridisation.

 

Results show both stereotyped and novel spatial patterns and allow us to associate the genes with organs, such as the ovaries, which prove to be an important source of developmental signals in tapeworms, just as they are in other animals including ourselves. These data provide a comprehensive picture of the factors governing tapeworm development and offer an effective means of identifying the 'hidden synapomophies' that underpin key innovations in form.

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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The boredom of belemnites: endoliths in belemnite guards from the Cretaceous Speeton Clay

 

 

Paul D. Taylor

Earth Sciences Department, Natural History Museum.

 

Tuesday 12 November- 4pm

Earth Sciences Seminar Room  (Basement, WEB 05, the previous Mineralogy Seminar Room)

 

 

The Early Cretaceous Speeton Clay Formation is renowned for its rich and diverse belemnite fauna. During October 2009 and March 2011 NHM field parties collected numerous examples of Speeton belemnites from the coastal exposures of the Speeton Clay south of Filey in East Yorkshire. These collections have been used in a research project, undertaken jointly with Consuelo Sendino and Museum volunteer Jane Barnbrook, on the previously unstudied biota of boring organisms that infested dead belemnite guards lying on the Cretaceous sea floor.

 

At least 15 ichnotaxa of borings can be recognized, ranging from brachiopod pedicle attachment traces (Podichnus), to rosette-like traces believed to have been made by foraminifera (Semidendrina), and putative fungal microborings (Orthogonum and Saccomorpha). The study of these endoliths can provide evidence for palaeoenvironmental conditions on the sea floor during deposition of the Speeton Clay.

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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Phylogenetics and evolution of some early and oddball plants

 

Sean Graham

University of British Columbia

 

Friday 8 November 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)


My research group works on multiple problematic nodes in the plant Tree of Life. Here I focus on two major subjects from phylogenetic and evolutionary perspectives: (1) The 'early' aquatic flowering-plant family Hydatellaceae; (2) the mycoheterotophic plants, which are diverse lineages of non-photosynthetic plants that rely on fungi for their carbon budget.

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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EARTH SCIENCES DEPARTMENT SEMINAR

 

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Mixing, mingling and enclave crumbling in the post-Minoan dacitic magmas of Santorini volcano, Greece

 

Chiara Maria Petrone,

Earth Sciences - Natural History Museum

 

Tuesday 29th October - 4.00 pm

Earth Sciences seminar room

(Basement, WEB 05, the previous Mineralogy Seminar Room)

 

 

The post-caldera islets of Palea- and Nea-Kameni formed as a result of nine eruptive events from A.D. 46-47 to 1950 in the center of the Santorini Minoan caldera. The erupted products are represented by dacitic lava flows and domes hosting basaltic to andesitic mafic enclaves. Dacitic rocks have low porphyritic index that increases with time, whereas their degree of evolution decreases pointing to the composition of the mafic enclaves. Enstatite contents of pyroxene and anorthite contents of plagioclase decrease from mafic enclaves to host lavas. Sr isotopes systematically increase with time and toward the less evolved composition of lavas and mafic enclaves, whereas Nd isotopes decrease. Whole rocks and mineral separates of mafic enclaves from the younger events are more Sr-radiogenic than their host lavas, the opposite occurs in the A.D. 46-47 lavas and enclaves.

 

Mixing and mingling processes between dacitic and mafic magmas, along with crumbling of the mafic enclaves in the host lavas are responsible for the observed textural and geochemical characteristics of the dacitic host lavas. The variations of Sr-Nd isotopes with time in the enclave magmas seem to indicate assimilation of limestone from the basement by the most mafic magmas; this process is associated to new mafic magma inputs and femic phase crystallization. A shallow layered reservoir with dacitic magmas overlaying lower mafic magmas is supported by our data. Crystal fractionation and cumulitic processes affect the lower part of the plumbing system allowing further layering of the mafic magmas, generating the variable and complex textures shown by the mafic enclaves. Different portions of the layered reservoir were frequently and variably sampled during time, as testified by variable types, compositions and distributions of mafic enclaves in the different eruptions. All this allows us to suggest periodic arrivals of mafic magmas in the post-Minoan plumbing system of Santorini, also implying for a still active magmatic system whose behaviour needs to be fully evaluated, also in the light of the 2011-2012 unrest.  

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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