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Wed 19th March 12 – 1 pm Rm 312.222 |
Julien Bourdet CSIRO CESRE Gas detection in fluid inclusions using Raman spectroscopy Abstract Fluids in subsurface can be naturally sampled in rock micro-cavities and preserved for millions of years. Fluid inclusion analysis can provide useful data for geoscientists and Raman micro-spectrometry provide new constrains on their gas content. This presentation show examples of analysis and new developments on samples from oil and gas reservoirs and aquifers. Biographical Details Dr Julien Bourdet is conducting research to better understand hydrocarbon migration and accumulation processes and diagenesis of reservoirs using microscopy and specialised techniques such as fluid inclusions (Raman, FT-IR, UV-Fluorescence spectroscopy, PVTx), isotopy (Carbon and Oxygen) and experimentation (micro-capillary tubes, HPHT vessels). He has conducted numerous research and commercial projects into oil migration and accumulation in sedimentary basins in Australia, South-East Asia and China using CSIRO-patented fluid inclusion technologies. |
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Curtin Applied Geology Seminar, 19th March, Julian Bourdet on Raman Spectroscopy of Fluid Inclusions
Curtin Applied Geology Candidacy Seminar, Weds 12th March, Korien Oostingh on dating the Newer Volcanics of Victoria
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Weds 12th March 12 – 1 pm Rm 312.222 |
Korien Oostingh Curtin Applied Geology PhD Candidate Using ultra-precise 40Ar/39Ar data for development of new geochronology techniques, in order to model the emplacement and land surface evolution of the Cainozoic Newer Volcanic Province, Victoria, Australia. Abstract Young basalts are extremely difficult to date by the K-Ar and U-Th decay series, as they contain low K concentrations and generally lack minerals high in U and Th, such as zircon and titanite. However, our recent installation of a new generation multi-collector mass spectrometer (ARGUSVI) will allow measurement of Ar isotopes with unprecedented levels of precision and vastly improved sensitivity (up to 25 times better analytical precision for young basalts!). The 40Ar/39Ar geochronology technique is already widely used in geology due to its ability to test the reliability of the data via incremental step-heating analysis, but improved analytical precision, along with the recent improvement over the value of the decay constant allow an exceptional step forward in age precision and accuracy. In this PhD-research, new and ultra-precise ARGUSVI 40Ar/39Ar data will be used to build a robust age database for both olivine lamproites from Western Australia and other overseas locations, and young basalts of the Newer Volcanic Province (NVP) in Victoria, Australia. These data will be used for two purposes: (1) To cross-calibrate age results obtained from two new techniques that will be developed as part of this research; olivine U/Th-He geochronology and cosmogenic 38Ar exposure dating. Lamproites comprise an exceptional suite of minerals, which favourably partition K as well as U and Th. This makes them ideal for cross-calibration of olivine U/Th-He ages with 40Ar/39Ar ages derived from multiple minerals in the rock. The young basalts of the NVP will be used as a case study to test the potential of the newly developed olivine U/Th-He technique for dating mafic rocks with much lower U/Th concentrations. The presence of original flow top surfaces on samples as well as the limited land cover and erosion in Victoria, potentiates the calibration of the cosmogenic 38Ar exposure dating technique using the young NVP basalts. Development of the 38Ar cosmogenic exposure dating technique could provide enhanced information on landscape evolution, elucidating a history of land mass cover and surface erosion and could be applied to a myriad of geological problems. (2) A second aspect of this research will combine geochronology with new and existing elemental and isotope geochemistry to develop improved emplacement models for these eruptive features. Current models oppose mantle plume vs. shallow mantle melting scenarios but these are based on very limited datasets. New olivine noble gases (e.g. He, Ne, Ar) and Sr, Nd, Pb and Os isotope analyses will help us decipher between the various available models. |
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Curtin Applied Geology Special Seminar Tues 11th March 2 – 3 pm Rm 312.222 Boris Kaus Professor, Geophysics and Geodynamics, Johannes-Gutenberg Universität. Mainz Insights in the physics of the Earth by combining models and observations
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Tues 11th March 2 – 3 pm Rm 312.222 |
Boris Kaus Professor, Geophysics and Geodynamics, Johannes-Gutenberg Universität. Mainz Insights in the physics of the Earth by combining models and observations Abstract Better understanding the physics of the Earth is remains one of the goals of the solid Earth sciences. Whereas geophysical methods give a fair idea of the structure of the present-day Earth, geological data indicate that most processes occur over millions of years and thus tell us something on how the Earth behaved on a much longer timescale. If we want to reconcile both types of data, we need models that describe how the lithosphere deforms and results in mountain belts such as the Himalayas. However, most geological tectonic models are just cartoon models drawn in Illustrator. They satisfy the geological (and often geophysical) data, but they do not necessarily tell us all that much about the underlying physics of the lithosphere and the mechanics of deformation. As a result, there are many competing geological models that can explain the same data sets. A different approach is to use thermo-mechanical numerical models to simulate collision scenarios on the computer. Over the last decade, such models have become quite sophisticated and we can now take realistic rock rheologies into account that vary from brittle (or elastoplastic) under low temperatures to ductile (or viscous) at higher temperatures. I will give an overview of recent progress in this field using examples from my research group. Typically, geodynamic models are used in a forward manner, in which various theoretical scenarios are simulated as a function of changing parameters such as plate speed, thermal structure of the crust and lithosphere and rock rheology. The best fitting models are the ones that appear to be most consistent with the data. This does teach us something about how lithospheric collision could have occurred. Yet, since the number of model parameters is large and the models remain computationally intensive even in 2D, we cannot check every parameter combination. The result is that we often cannot isolate the key parameters that control the physics of lithospheric and crustal deformation in each case. Here, I will discuss two examples to illustrate that it is possible to go a step further and to constrain the physics of the Earth on both crustal and lithospheric scale in a more direct manner. The first example is related to crustal scale deformation in the Zagros Mountains, where space- and surface based geophysical and geological datasets put tight constraints on both the present-day structure and the geological evolution of the crust. Numerical models can fit the data, but only under very specific conditions. By analysing the numerical models in a systematic manner we are able to better understand the physics of crustal scale deformation on one hand and to simultaneously constrain the rheology of the crust on geological timescales. The second example concerns the structure and rheology of the present-day lithosphere in active collision belts. Whereas the large-scale structure of the lithosphere is often reasonably well known from mostly seismological and potential field methods, the rheology of the lithosphere remains poorly understood. Yet, it is the rheology that defines to a large extent how the lithosphere deforms and how it is coupled to the underlying mantle. Changing rheological parameters such as the effective viscosity of for example the mantle lithosphere can have a huge effect on the surface velocity or on mantle anisotropy. We have exploited this effect to develop a joint geodynamical-geophysical inversion technique that combines parallel 3D forward models of gravity and lithospheric-scale deformation with a Monte-Carlo inversion method. For a simple setup we can demonstrate mathematically that this joint approach results in a unique solution (as opposed to inverting for gravity alone which is a well-known non-unique problem). More realistic 3D cases are computationally significantly more challenging but they remain doable with today’s computers and results show that the method is capable of successfully determining the ‘best-fit’ parameters with uncertainty bounds. Combining dynamic forward models with geophysical observational constraints and inverse models is thus a very promising future research direction that will likely teach us more about the physics of the Earth. |
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Wed 5th March 12 – 1 pm Rm 312.222 |
Kliti Grice WA-OIGC, Curtin University Mass Extinctions and Environmental Implications Abstract Kliti will present research findings from her team using a multidisciplinary approach (ranging from biomarkers, stable carbon and hydrogen isotopes of molecules, palynology, paleontology, petroleum systems and sedimentary geochemistry). She will provide a summary of their findings published in Science (Grice et al., ), Nature Scientific Reports (Melendez et al., ), Geology (Jaraula et al.,), Geochimica et Cosmochimica Acta (Williford et al.,) and Earth and Planetary Science Letters (Tulpani et al.; Grice et al., Nabbefeld et al.,). 2. How similar were three of the five mass Extinctions on Earth? (end- Permian, end-Triassic and Late Givetian – Early Frasnian 3. How did exceptional preservation of biological material occur? (The most extensive diagenetic continuum of 380 million years old (including intact geomolecules-sterols). Biographical Details Kliti Grice is the John Curtin Distinguished Professor Kliti Grice, holds an ARC Professorial DORA and is Director of the WA-Organic and Isotope Geochemistry program. |
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Curtin Applied Geology Seminar: Wednesday 26th Feb, Professor Peng on mafic dyke swarms in the North China Craton
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12 – 1 pm Rm 312.222 |
Peng Peng Institute of Geology and Geophysics, Chinese Academy of Sciences A tale of the North China Craton by Proterozoic mafic dyke swarms Abstract The major Proterozoic mafic dyke swarms, as well as rift systems in the North China Craton and their implications for palaeogeography reconstruction and lithospheric evolution will be reviewed based on our systematic investigation. These dyke swarms could be grouped as three: the Middle Paleoproterozoic group (2150 Ma, 2050 Ma, 1970 Ma and 1890 Ma dyke/sill swarms) could implicate for the tectonic subdivision and the forming of the craton; whereas the Late Paleoproterozoic (1780 Ma, 1730 Ma, 1680 Ma and 1620 Ma) and the Early Neoproterozoic (925-890 Ma) groups are potentially important in reconstructing the rifting events and the configuration of the North China Craton in Proterozoic supercontinents. These dyke swarms are also important in understanding the evolution of the sub-continental lithospheric mantle. Our studies tell another story for this 3.8 Ga-old-craton. Biographical Details Peng is a professor of petrology and Precambrian geology at Institute of Geology and Geophysics, Chinese Academy of Sciences (Beijing). He is interested in using mafic dyke swarms to reveal the Precambrian lithospheric evolution as well as palaeogeography of particularly the North China Craton. |
Curtin Applied Geology Seminar: Wednesday 12th Feb, Holly Stein on the Re-Os library in Earth’s crust
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Wed 12th February 12 – 1 pm Rm 312.222 |
Holly Stein Director, AIRIE Program, Colorado State University, USA, and Professor, CEED-University of Oslo, Norway The Re-Os library in earth’s crust Abstract Re-Os has irreversibly changed our geochemical understanding of earth’s crust. What was first a gateway to directly dating sulfides in ore deposits is now a tool for gaining understanding in how petroleum systems work. As an outgrowth of these resource-based applications, Re-Os also yields information on fundamental geologic processes. Re-Os isotope geochemistry can tell us about paleoenvironmental changes that produced global mass extinctions of life. Re-Os isotope geochemistry can tell us about fluid-enhanced metamorphic-magmatic activity in the deep crust. This talk is for both beginners and more advanced students, with either little or large knowledge of isotopic geology. Biographical Details After obtaining her Ph.D. at University of North Carolina at Chapel Hill and a Gilbert Fellowship at the U.S. Geological Survey in Denver and Reston, Dr. Stein set out to work with the mineral industry. Her laser focus was the how and why of sulfide formation in economic quantities. During this time she developed a keen interest in geochronology as a tool to track the movement of metals, and ultimately hydrocarbons in the earth’s crust. Dr. Stein is a Fulbright Scholar, and received the SEG Silver Medal in 2005 and the Helmholtz-Humboldt research prize in 2008. She founded the AIRIE Program at Colorado State University in 1995, and is a professor at a newly announced Norwegian Centre of Excellence (CEED, Center for Earth Evolution and Dynamics) at the University of Oslo. She and her team pioneered Re-Os dating of sulfides. They are particularly noted for establishing Re-Os dating of molybdenite as a highly respected chronometer in the geochronology community. More recently the AIRIE group has worked innovatively to bring Re-Os to the petroleum industry in a creative geologic context. The AIRIE Program routinely dates organic material extracted from source rocks for precise depositional ages, time-scale refinement and global correlations. Most importantly, they use Re-Os data from source rocks to characterize paleo-environment and connect to the timing of hydrocarbon maturation and migration through direct dating of oils. The success of the AIRIE Program in bringing forefront research to real-world application is measured in its unwavering support from industry, as the entire workings of the Program are based on externally-derived funding. |
Chemistry Seminar – Prof. Bart Kahr (NYU) – Friday 21st February @ 2PM – Bld 500 Exhibition space
Hückel Theory and Optical Activity
Prof. Bart Kahr
Department of Chemistry, New York University, NY
Hückel theory is an approximate molecular orbital theory for planar, conjugated hydrocarbons whereas optical activity is typically associated with molecular chirality, a geometrical property of three-dimensional structures. Hückel theory and optical activity are subjects that at first blush brook no intersection. Why the conjunction “and” in the title? Some achiral compounds can indeed be optically active, but these have been traditionally excluded from considerations of optical activity because the spatial average of the optical activity of such compounds is zero. Thus, nothing can be measured in solution. On the other hand, these are perfectly appropriate targets for measurement on crystals. Optical rotations and rotatory strengths are here calculated for planar, conjugated hydrocarbons with the aim of determining to what extent the sum-over-π→π* rotatory strengths are sufficient to account for non-resonant optical activity, as well as to what extent qualitative molecular orbital theory can be used to interpret chiroptical structure-property relations. It is shown that by restricting our analyses to planar π-systems, an intuitive understanding of the vexing property of optical activity is forthcoming for the following reasons: Wave functions under the Hückel approximations are simply determined and graphically computed to yield transition dipole and quadrupole moments; the forms of the gyration tensors are given by symmetry with simple representation surfaces whose orientations are completely (C2v) or partly (Cs) determined by symmetry; transition electric dipole and magnetic dipole moments have fixed, orthogonal dispositions relative to one another, and the most optically active directions are found at their bisectors. Throughout, the emphasis is on reckoning long wavelength optical rotation using simple models that are part of organic chemistry pedagogy. Attempts to measure the optical activity of oriented, isolated achiral molecules is also discussed.
Curtin Applied Geology Seminar: 4th December, Oliver Nebel on Isotopic Mantle Reservoirs in Space and Time
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Wed 4th December
12 – 1 pm
Rm 312.222
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Oliver Nebel
Research School of Earth Sciences, Australian National University
Isotopic mantle reservoirs in space and time
Abstract It is complicated. In the early- to mid-1980’s, geochemists noticed that intra-plate oceanic island basalts (OIB) are isotopically distinct from their mantle-derived cousins born at divergent plate margins, the mid-ocean ridge basalts (MORB). The range of proxies employed to study the origin and nature of this oddity includes radiogenic Sr-Nd-Pb-Hf-Os-He isotopes and an ever-growing number of stable and short-lived isotope systems. From these studies, a picture has emerged within the geochemical community that most (but not all!) researchers nowadays adopt and further develop.
The similarity of some OIB with the chemistry of the crust has led to the idea that once surface-exposed crustal rocks were subducted to the mantle where they subsequently heated to become buoyant and return to the surface in mantle plumes. These then burn through the oceanic plates where they erupt as OIB. However, the range in OIB isotope composition requires multiple, isotopically distinct components, commonly referred to as mantle endmembers, namely enriched mantle 1 (EM1-lithospheric mantle?), enriched mantle 2 (EM2-subducted sediment?), high-µ (HIMU-oceanic crust?), the focal zone component (FOZO, subdivided into FOZO-A (australis) and FOZO-B (borealis)), or the primitive He-mantle (PRHEMA) or the SCHEM mantle (sub-chondritic Earth model mantle) or simply the primitive mantle (PM). Modes, loci and timescales of mantle storage remain unknown. In addition, the mantle reservoirs seem to be present to various proportions in different OIB locations around the globe, yet only some of them mix with the depleted MORB mantle (DMM) sourcing mid-ocean ridges. The latter is also isotopically heterogeneous, with MORB from the Indian Ocean (Indian-type mantle, ITM) being distinct from Atlantic or Pacific MORB (ATM, PTM), all of which depict a spectrum of compositions rather than being sourced from one homogeneous DMM. Illuminating the true nature of these mantle reservoirs is further complicated by the unknown age of the subducted endmembers and the time at which they experienced additional parent-daughter fractionation, either during subduction or within the mantle. I will give an overview on the status-quo of mantle heterogeneity from a geochemical perspective with a focus on HIMU OIB. |
Chemistry@Curtin Seminar: Dr Ben Fraser – Thursday 28th November – 4PM Exhibition space – Bld 500
Dr Ben Fraser
Organic Chemistry Task Leader, ANSTO Lifesciences
Positron emission tomography (PET) is a molecular imaging technique that gives detailed three- dimensional information on functional processes in the body. PET has established diagnostic applications in oncology, neurology and cardiology but is also proving extremely useful in drug discovery and for understanding disease pathology. [18F]Sulfonyl fluorides are a relatively unknown functional group for [18F]radiolabelling. We have systematically explored the effects of temperature, precursor amount, reaction time, precursor sterics, precursor electronics, presence of water and other nucleophiles upon the radiochemical yield and subsequent stability of various substituted [18F]arylsulfonyl fluorides. The findings from this study increases the very limited fundamental knowledge of [18F]sulfonyl fluoride radiochemistry and provides insight for the future design of [18F]sulfonyl fluoride based radiotracers.!
Chemistry@Curtin seminar – Friday 22nd November @ 4PM – Dr Boris Mizaikoff – Exhibition space Bld 500
Miniaturized Mid-Infrared Sensor Technology: Potential and Applications
Dr. Boris Mizaikoff
University of Ulm, Institute of Analytical and Bioanalytical Chemistry, 89081 Ulm, Germany | uni-ulm.de/iabc — boris.mizaikoff@uni-ulm.de
State-of-the-art sensing platforms ideally benefit from miniaturized and integrated optical technologies providing direct access to molecule-specific information. With point-of-care and personalized medicine becoming more prevalent, detection schemes eliminating reagents or labeled constituents facilitate localized on-site analysis close to real-time.”
However, decreasing the analytically probed volume may adversely affect the associated analytical figures of merit such as the signal-to-noise-ratio, the representativeness of the sample, or the fidelity of the obtained analytical signal. Consequently, the guiding paradigm for the miniaturization of optical diagnostic devices should be creating chem/bio sensing platforms that are as small as still useful, rather than as small as possible, and that smartly capitalize on integrated photonics.”
Mid-infrared (MIR; 3-20 μm) sensor technology is increasingly adopted in environmental analysis, process monitoring and biodiagnostics due to the inherent molecular specificity enabling the discrimination of molecular constituents at ppm-ppb concentration levels in condensed and vapor phase media. Recently emerging strategies taking advantage of innovative substrate-integrated waveguide technologies such as mid-infrared transparent fiberoptics, hollow waveguides and planar semiconductor waveguides (e.g., MIR Mach-Zehnder interferometers) in combination with highly efficient light sources such as miniaturized IR spectrometers and broadly tunable quantum cascade lasers facilitate compact yet robust MIR diagnostic platforms for label-free chem/bio sensing and diagnostics that may readily combine with complementary analytical tools.”
