Date: Tuesday, January 22, 2008 — Friday, January 25, 2008
Location: Physical Research Laboratory, Ahmedabad, India
The aim of the conference is to provide a forum for discussion on the present status and future perspectives in utilising modern geochemical and isotope techniques to understand the origin and evolution of the solar system, the chronology and causes of major events on Earth, past climate, and dynamics of various reservoirs in Earth. PRL is actively engaged in all these areas of research for the past several decades and the conference is organised as a part of its Diamond Jubilee Celebrations.
The main themes of the conference will be:
The conference format will comprise plenary addresses (covering broad aspects of each theme) and invited talks. A selected number of contributed papers will be scheduled for oral presentations and the other contributions will be put up as posters. The language of the conference shall be English.
Date: Monday, March 24, 2008 — Friday, March 28, 2008
Location: Austria Center Vienna, Vienna, Austria
Includes the following sessions:
Session GMPV27 Large Igneous Provinces and their impact on life and environment
Evidence of synchronism between the formation of many large igneous provinces (LIPs) emplacement and major rapid environmental and biotic crises has led us to consider a causal relationship between these events. The testing of such a hypothesis requires a multidisciplinary approach to studies of the formation of LIPs and the consequences on life and the environment. We invite papers on the topic of the generation and eruptions of LIPs, including both basaltic and silicic examples, as well as studies of the factors that control the accumulation of large, eruptible magma bodies, the evolution and dynamics of such bodies (including magmatic volatile concentrations), the volcanology of large volume eruptions (effusive and explosive). Field-based studies on the climatic and environmental impact of large eruptions and atmospheric model-based assessments of the climatic and environmental impact of large igneous province eruptions are also welcome. Finally, palaeontological studies of the impact of volcanism on flora and fauna and cross-disciplinary studies combining evidence from the ocean sedimentary and land records are encouraged.
Session GMPV30 Geochronology of igneous processes
Single crystal Ar/Ar dating and ion microprobe U-Th/Pb multiple age determination in a single crystal show that magma residence times may vary from a few thousand years to more than several hundred thousands of years. Complementary time information obtained from modelling the re-equilibration of the chemical zoning of crystals shows that magmatic assimilation or magma mixing can be much shorter, a few decades or less. This session wants to expose the recent geochronological findings on magmatic systems and move towards establishing a hierarchy of processes according to their duration and the size of the system. We welcome abstracts that use any geochronological tool to constrain the rates of igneous processes. Topics may range from the time involved for the construction of a large igneous province or plutonic complex, the rates of magmatic differentiation, to the duration of processes necessary for triggering a single eruption.
Session IS20 Plume-like instabilities in the mantle – hotspots, wetspots or displaced material from the transition zone?
This session brings together an interdisciplinary group of researchers interested in the problem of how convective instabilities in the upper mantle originate and what their relationship is to magma generation processes (“hotspots”) and lithosphere geodynamics. In recent years a number of high-resolution integrated seismic projects across regions of Tertiary to recent volcanism in central Europe have, in collaboration with detailed geochemical studies, demonstrated the existence of a number of small-scale, almost cylindrical, upwellings of low-velocity mantle material (~ 100-150 km in diameter). These “diapiric instabilities” have some characteristics in common with those of “classical” mantle plumes (e.g. thermal and geochemical anomalies, associated basement uplift), but a number of distinct differences:
1. They are much smaller in size than classical plumes
2. They do not appear to “have” a plume head
3. They appear to originate in the Transition Zone (410-660 km depth)
The existence of these small-scale plume structures suggests that there might exist a number of different classes of mantle plumes, originating from different depths within the mantle (e.g. the Transition Zone, the lower mantle or the CMB). So far such structures have only been postulated to exist beneath the European continent (e.g. the Massif Central, the Eifel and possibly the Bohemian Massif), but it is highly likely that similar structures exist beneath other continents.
The following observations can be made concerning the origin of these upper mantle plumes:
They are small-scale convective instabilities within the upper mantle beneath Europe which appear to originate in the Transition Zone (410-660km depth)
There is a strong correlation between the location of the “upwellings” and lithospheric architecture – suggesting some form of top-down control.
· The upwellings appear to be concentrated around the edge of a region of subducted slabs at the base of the upper mantle.
Basaltic magmas derived by decompression partial melting of the upwelling mantle “diapirs” have the distinctive geochemical signature of a common mantle source component – the European Asthenospheric Reservoir (EAR). The EAR could be the product of outflow from one or more lower mantle plumes.
The location of these upper mantle instabilities could be controlled by a number of factors, such as:
In our session, we are particularily interested in presentations which could broaden out PLUME to other areas of the world where the Transition Zone (410-660 km) is seismically fast and might also be a "slab graveyard". We welcome especially presentations of researchers working on the mantle Transition Zone worldwide - particularly if they can see a link between recent surface volcanism and seismically fast materials in the TZ. Another area of particular interest does involve researchers interested in high pressure metamorphism of subducted oceanic crust and sediments - in the context of how much water might be recycled (in hydrous minerals) into the TZ.
Date: Monday, June 16, 2008 — Friday, June 20, 2008
Location: Busan, South Korea
Includes the following session:
Session SE59 Post-collision magmatism: plumes versus top-down plate tectonics?
As subduction gives way to plate collision, magmatic activity tends to progress from HFSE-depleted calc-alkaline to potassic and ultrapotassic types. These are succeeded by voluminous OIB-like basalts, marking post-collision transtensional ‘nodes’ and possibly reflecting perturbations of ductile sublithospheric mantle. These late-stage magmas are mostly non-potassic and rich in HFSE and include both tholeiites and variably SiO2-undersaturated types. Examples – linked in space and time to recent and ongoing Tethyan collisions – include those in western and eastern Europe, eastern and southeastern Asia, and the Levant and northern Africa. Rarely, strongly potassic types HFSE-rich basalts appear, distinct from the shoshonites and lamproites commonly associated with collisions, examples appearing in NE China, Central Spain, and the western Germany. Geochemical and geophysical studies have led to robust debates, for example, as to whether the basalts reflect deep-sourced plumes or the effects of plate-induced upper mantle displacement. This session will be an opportunity to discuss current models pertaining to subcontinental mantle flow fields in relation to intraplate basalt genesis.
Date: Sunday, July 13, 2008 — Friday, July 18, 2008
Location: University of British Columbia, Vancouver, Canada
Provisionally proposed themes include Early Earth, Continental Crustal Evolution, Mantle Dynamics, Mantle Geochemistry and Magmatic Processes.
Conference-related fieldtrips include:
Wrangellia flood basalts on Vancouver Island: an accreted Late Triassic oceanic large igneous province
Leaders: A. Greene (firstname.lastname@example.org), G. Nixon, N. Massey, J. Scoates
Date: Post-conference; July 18-21
Date: Wednesday, August 6, 2008 — Thursday, August 14, 2008
Location: Oslo, Norway
Includes the following sessions:
Session MPI-04 Mafic dyke swarms: a global perspective
Because of great depth and lateral extent, mafic dyke swarms provide the most complete record of short-lived, mantle-generated magmatic events through time and space. Our increasing ability to date mafic dyke rocks precisely has greatly enhanced their importance as high-resolution markers in time. Collectively, the record of mafic dyke swarms provides information on “the pulse of the Earth” - that is, the rhythm of mantle melting events through time, from minor rift-related events, to the largest known igneous events (LIPs) on the planet extruding millions of km3 of basaltic melt over short intervals of time (<1 my). Linked with precise ages, mafic dykes swarms become an unparalleled source of diverse and high-quality information: on tectonics and secular evolution, age and location of igneous centres, palaeostress directions, strain gradients, key palaeomagnetic poles, palaeo-intensities of the core dynamo, plume frequency, mantle sources, and much more. Successive short-lived dyke events define “bar codes” that identify a piece of crust and its original “nearest neighbours”. Thus they are the key to palaeogeographic reconstructions. “Bar coding” the geological record will allow, in principle, a full reconstruction of Earth’s palaeogeography, back to ca. 2.6 Ga. This session will bring together all those interested in these and other aspects of mafic dyke swarms.
Session MPI-05 Large Igneous Provinces: initiation, evolution and origin
The events during initiation of some mafic Large Igneous Provinces (North Atlantic, Ferrar, and Karoo Igneous Province) were studied recently, with spectacular results and new (?) concepts. In all cases we see that early emplacement occurred as sills in a shallow crustal environment with abundant magma-wet sediment interaction and diatreme formation. However, this initial character may be due to the local geology of young unconsolidated sediments overlying crystalline basement. We can neither identify an initial phase of small volume magma emplacement, nor a regular early involvement of molten continental crust. In the Ferrar Province, we recognize that the magmas belong to the tholeiitic differentiation series with the early intrusive andesitic magmas being more evolved than the later plateau forming basaltic andesitic lavas. Which of these observations are of general relevance for LIP formation and are crucial pieces in the big puzzle? How are Silicic Large Igneous Provinces initiated, do they start with a mafic initial phase? We invite any geoscientist working on the topic of initiation of mafic or silicic LIP to present his/her new data from other LIPs on earth in order to gain a more precise understanding of the early processes during production, evolution and emplacement of such catastrophic volumes of magma.
Session MPE-02 Experimental petrology and the generation of plume magmas
Mantle plumes are believed to be the underlying cause of hotspot volcanism. Wherever plumes originate, there is broad agreement that they sample a volume of the mantle that is distinct from the shallow source region of passively spreading mid-ocean ridges. The aim of petrology research of plume melting is to constrain the pressure and temperature conditions of melting and the source composition in order to improve our understanding of plumes and the evolution and dynamics of the mantle. The mantle is made up of various components, including remnant primordial mantle, depleted mantle formed as the residue of continental differentiation, subducted oceanic crust and lithosphere, and smaller volumes of sediments and continental lithosphere. Which of these reservoirs are present in the plumes, and to what degree are they represented in the melts? Do different plumes sample different reservoirs, or do the varying chemical signatures of plumes derive from differences in the melting dynamics? Are heterogeneities spread out randomly as blobs or filaments, are they stretched out as strings along the conduit, or are plumes radially or laterally zoned? Can the spatial and secular variability of plume lavas help determine the pattern of plume heterogeneity? We invite all contributions that apply petrology to melting at hotspots, but encourage a focus on the global perspective. We also welcome petrological evaluations of alternatives to the plume hypothesis.
Session MPV-03 Flood basalt volcanism and stratigraphy
Over the last two decades stratigraphic and volcanological research has revolutionised our views of LIP construction and the mechanisms of the eruption that are responsible for their formation. The purpose of this symposium is to bring together research that sheds light on shallow subsurface and surface processes involved in construction of flood basalt provinces of all ages as well as their potential climatic and environmental impacts. The symposium will focus on the following areas of research: upper crustal plumbing systems of LIPs; geochronology of flood basalt successions; volcanic, petrochemical and palaeomagnetic stratigraphy of LIPs; eruption styles, mechanisms and lava emplacement modes at LIPs; gas fluxes from flood basalt eruptions; potential climatic and environmental impacts of flood basalt eruptions and the link to mass extinctions.
Session EUR-08 North Atlantic Igneous Province stripped: origin, magmatic activity, crustal processes and plate kinematics
The North Atlantic Igneous Province (NAIP) which includes the UK, Ireland, the Faeroes, Greenland and the West Greenland-Baffin corridor is one of several well-known Large Igneous Provinces (LIP) temporally correlated with continental break-up. The NAIP likely owes its origin to the Iceland plume and broadly corresponds in time to the initiation of seafloor spreading in the NE Atlantic. It is also believed to have triggered global climate changes, with knock-on effects for the biosphere and sedimentary facies. In the last few decades, the Atlantic-Arctic margin has received much attention, partly as a result of hydrocarbon exploration, leading to a rapidly expanding, onshore and offshore geological and geophysical data set. This provides a unique setting to derive new insights into causal links between timing and style of magma emplacement, crustal processes, plume arrival, plate kinematics, uplift, subsidence and the evolution of sedimentary basins. In this session we aim to paint a more comprehensive picture of the NAIP, the complex thermal history of the North Atlantic region and its role in shaping the North Atlantic geology. We welcome contributions from all disciplines that will further and challenge our knowledge of the Mid-Cretaceous to present North Atlantic magmatism, its causes before, during and after continental break-up.
Date: Sunday, August 17, 2008 — Friday, August 22, 2008
Location: University of Iceland, Reykjavik, Iceland
Includes the following sessions:
Mantle plumes and plume-ridge interactions
This session is dedicated to geodynamic issues, including mantle convection, the origin and evolution of plumes, mantle melting, melt transport and along-axis melt variability. We seek contributions from all areas of research on mantle plumes, plate-spreading, V-shaped ridges, seamounts, large igneous provinces and orogenic episodes.
This session will focus on:
Intraplate volcanism – continents and oceans, from scoria cones to large igneous provinces
Intraplate volcanism provides key insights into magma sources and magmatic processes. This volcanism encompasses a wide array of eruptive styles and products, and, on the continents, is an important component of volcanic risk in some areas. This session will combine both the continental and ocean floor perspectives on the nature of ancient and modern intraplate volcanic activity, from source through eruption, on a wide range of scales from small localised eruptions to large igneous provinces.
This session will focus on:
Frontiers in large igneous provinces research
Over the last fifteen years it has become widely accepted that Large Igneous Provinces (LIPs) are produced by melting mantle plumes. However the link between LIPs and mantle plumes has recently been challenged. How confident are we that LIPs are produced by mantle plumes? Are there any aspects of LIPs that cannot be explained by the plume theory? Are there viable alternative hypotheses? Are there some LIPs that are better explained by alternative models?
This session will focus on:
Construction of large igneous provinces and mass extinctions
Mass extinctions are global phenomena that represent some of the most dramatic events in the geological history and arguably no events have had more influence on evolution of life on Earth. They are generally thought to have lasted for <1 Myrs and the fact that they define all of our key geological boundaries is the best testimony of their significance. Despite ample research cause of mass extinctions is still one of the great outstanding questions in Geosciences. The synchronicity of mass extinctions and LIP volcanism in the Mesozoic and the Cenozoic has led many to postulate a causal link between the two events. However, the mechanism by which LIP volcanism may have induced mass extinctions is still unclear and strongly debated. In this session we like to focus on the questions:
Did LIP emplacement lead to dramatic environmental change?
Can LIP volcanism trigger mass extinctions and, if so, how?
The aim is to bring together research that sheds light on the potential climatic and environmental impacts of flood basalt volcanism and their link to mass extinctions via studies of LIP-related stratigraphy as well as shallow subsurface and surface processes involved in construction of LIPs.
The session will focus on:
Date: Friday, September 5, 2008 — Wednesday, September 10, 2008
A field meeting of the Volcanic and Magmatic Studies Group
Location: Ardnamurchan, Scotland
Leaders: D. Brown (email@example.com), B. O’Driscoll
Includes the famous ring complexes, layered intrusions, cone sheets, magma mixing, mass flow deposits, megablocks, flood basalts, and a distillery visit!
Date: Sunday, September 14, 2008 — Monday, September 22, 2008
Location: Dali, Yunnan Province, China
Includes the following session:
Roles of mantle plumes/superplumes in supercontinent evolution
This session will focus on mantle plumes and large mantle upwellings and their role in the supercontinent cycle. Topics will include, but are not restricted to, 1) the role of descending slabs in generating mantle plumes in the D” layer; 2) geophysical models of mantle plume events through time and their relation to supercontinent formation and breakup; 3) the geologic record of mantle plume activity through time; 4) comparison of LIP and continental crust age spectra through time; 5) LIPs (including LIP-type greenstones) and their relation to mantle plumes through time; and 6) weak plumes and strong plumes: origin, source and possible role in supercontinent breakups. We encourage presentation of controversial papers that will generate lively discussion.