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Curtin University
Science Seminars

Alex Walker (Curtin University) on “The Heavy Mineral Map of Australia: A Continent-Scale Mineral Dataset”

By Hugo Olierook 5 December 2022 Applied Geology Earth & Planetary Sciences Comments off

Wed 7th December 2022 @ 12:00 nn, 312.222 and online via Webex (meeting #: 2654 563 1797 and password: 6VwJRMFiM95)

Abstract:

Mineral exploration is challenging in much of Australia with mineral resource potential frequently concealed beneath regolith. Heavy minerals, such as zircon, spinels, and cassiterite, are widely used by mineral explorers and can provide information on geochemistry, alteration and mineralisation through cover.

The joint Geoscience Australia-Curtin University Heavy Mineral Map of Australia (HMMA) is an ambitious, first of its kind project that aims to define the heavy mineral baseline across Australia. The heart of the HMMA project is a sample suite comprising more than 1,300 catchment outlet sediments collected from most of Australia’s drainage catchments as part of the National Geochemical Survey of Australia. The mineralogy of these sediments reflects the geology of the hinterlands from which they are derived, and concentrations of certain heavy minerals can potentially indicate the presence of economically important critical minerals on a regional scale. Partial heavy mineral datasets covering areas of economic interest have been released through 2022, with the HMMA due to be completed in 2023.

When finished, we envisage the Heavy Mineral Map of Australia will contribute significantly to mineral prospectivity analysis and modelling as a pre-competitive dataset available to both mineral explorers and researchers alike.

Short bio:

Alex is a researcher and mineralogist at the John de Laeter Centre in Curtin University, where he spends much of his time generating and exploring large mineralogical datasets. He completed a PhD in Applied Geology at Curtin University in 2019, which characterised sulphur isotope and sulphide trace element signatures in the Fraser Zone of the Albany-Fraser Orogen. Alex’s research interests center on applied, economic and exploration geology, with a current focus on world-class mineralisation in Western Australia.

Ziyi Zhu (Australian National University) on “Unravelling the evolution of continents using detrital zircons from modern rivers”

By Hugo Olierook 23 November 2022 Applied Geology Earth & Planetary Sciences Comments off

Wed 30th November 2022 @ 12:00 nn, 312.222 and online via Webex (meeting #: 2655 735 2039 and password: rZQ77e7XU8W)

Abstract:

Detrital zircons collected from Earth`s modern rivers provide a representative sample to study the evolution of the continental crust on a global scale. This is because most of the eroded material in modern rivers has experienced long-time sediment-sediment recycling, and thus they contain detrital zircons from source rocks of diverse origins, including the crustal segments that are currently inaccessible by surface geology.

In this talk, I will present three projects of my PhD research, which focus on using large data sets of zircon geochronology and isotope geochemistry to track a range of crustal processes throughout Earth’s history. In the first project, I used trace element geochemistry of 6911 detrital zircons from worldwide major rivers, together with their U-Pb isotopic ages, to document the relative abundance of zircons from S-type granites, which gives new quantitative insights into sediment melting in the different supercontinent cycles. In the second project, I used lutetium (Lu) content in zircons to identify those that came from the high-pressure zones of deep roots that underlie high mountains. The results of mountain-building history were compared with the variations in atmospheric oxygen levels and biological evolution. For my third project, combined zircon U-Pb, O and Hf isotopes are used to constrain the evolution and growth rate of the European continental crust.

Short bio:

I am a PhD candidate at the Australian National University working with Prof. Ian Campbell. I obtained my undergraduate degree at China University of Geosciences (Wuhan) in resource exploration engineering in 2017, after which I went to ANU for a PhD. My PhD projects focus on using large data sets of zircon age, isotopes and trace element compositions to infer Earth’s crustal evolution, including the formation of S-type granites, the growth of the continental crust, mountain-building events and the supercontinent cycles throughout Earth’s history. I am currently doing a  3-month internship project at CSIRO about “visualising Earth’s evolution with isotopic systems”, in which I am using combined geochronological and Sm-Nd isotopic data to visualise the continental evolution of Australia.

Damaris Butters (U. Bristol) on “Transcrustal, volatile-charged silicic melts revealed by zircon-hosted melt inclusions”

By Hugo Olierook 16 November 2022 Applied Geology Earth & Planetary Sciences Comments off

Wed 23rd November 2022 @ 12:00 nn, 312.222 and online via Webex (meeting #: 2652 439 4990 and password: JGf36T2PPgx)

Abstract:

The volatile contents of silicic crustal magmas inform models for volcanism, degassing behaviour, and hydrothermal ore formation. Volatile saturation pressures of phenocryst-hosted melt inclusions are generally restricted to late-stage, shallow magmas that have typically undergone substantial, ascent-driven degassing of CO2 and SO2. As an alternative approach, we directly sample the volatile contents of rhyolitic melt inclusions in the accessory mineral zircon. Our results reveal that zircons grow over an exceptional crustal depth range, from Moho depths (>25 km; deepest melt inclusion 31 km) to the upper crust (~5 km). Significantly, melt inclusions from porphyry copper deposit-related magmas have high melt inclusion CO2 contents (up to 3970 ppm), indicating CO2-rich sources (equilibrium fluid molar fraction CO2 up to 0.95). Deep crustal zircons are transported to shallow levels in silicic melts percolating through transcrustal mush systems and/or in rapidly ascending volatile-charged magmas.

Short bio:

Damaris received a Master’s degree in Geology from the University of Bristol, UK in 2017. Her dissertation focused on the formation of tourmaline orbicules in the Cornish Granites and associated pegmatites. She stayed at Bristol to pursue a Ph.D. on the microanalysis of zircon-hosted melt inclusions from barren and mineralised magmatic systems, which she completed in March 2022. She is now a postdoc at Bristol, undertaking brine-rock interaction experiments as part of the NERC CuBES project, to understand the formation of sediment-hosted Cu deposits. Damaris is currently a visiting research associate at Curtin, working on an IGO-funded trial study to develop geochemical proxies for LCT pegmatite formation.

Michael Brown (U. Maryland) on: “The emergence and evolution of plate tectonics on Earth: a petrological perspective”

By Hugo Olierook 27 October 2022 Applied Geology Earth & Planetary Sciences Comments off

Wed 2nd November 2022 @ 12:00 nn, 312.222 and online via Webex (meeting #: 2650 711 1383 and password: 2dpBV3Xe2T3)

Abstract:

Based on the crustal record of magmatism and metamorphism, Earth likely evolved from a single-lid (sluggish or squishy) to a mobile-lid tectonic mode during the late-Archean–early-Proterozoic. Time-constrained data show a strong temporal clustering of metamorphism associated with periods of supercontinentality and a close spatial relationship with inferred plate margins since the Archean. Statistical analysis shows that bimodality in T/P—a characteristic feature of convergent plate boundaries since 200 Ma—developed during the Paleoproterozoic and became increasingly distinct thereafter; late Archean metamorphism was unimodal. Thus, a strong case can be made for plate tectonics since the early Paleoproterozoic; a single-lid episode in the Mesoproterozoic seems unlikely. However, a peak in metamorphic T/P, dominant anorthosite and rapakivi suite magmatism, and longevity of passive margins in the Mesoproterozoic suggest a plate slowdown, as verified by geophysical modeling. Statistical analysis of time series of T/P and cooling rate identifies change points in the Paleoproterozoic and early Paleozoic, recording two state shifts: one following stabilization of subduction after the emergence of continents and the Siderian glaciations, which led to an enhanced sediment supply along continental margins and a period of increased orogenic activity throughout the amalgamation of Nuna, and another following the Cryogenian glaciations, which led to an increased sediment load in trenches that kick-started modern-style plate tectonics characterized by low T/P and UHPM. In the Archean, unstable subduction at various locations created conflicting signals in the geological record, and there is evidence of late-Archean regional plate-like behavior, but the shift to global plate tectonics cannot be confirmed before the early Paleoproterozoic. Lastly, the changing abundances of komatiites, anorthosites and kimberlites through time are consistent with an evolution from early bottom-up asymmetric, to symmetric, to modern top-down asymmetric mantle geodynamics.

Short bio:

Mike is an internationally recognized leader in the field of metamorphic geology, with an emphasis on crustal melting, the petrogenesis of granulites (including UHT metamorphism) and eclogites (including UHP metamorphism), and the relationship between metamorphism and tectonics. His research uses observations and laboratory data in petrology and structural geology, integrated with those from geochemistry and geochronology, and results from numerical modeling, to investigate orogenic processes at all scales, providing original contributions to and insight about heat and mass transfer and secular change.

Amy Elson (Curtin) on: “Descent from the Hyperthermals: Persistent Organic-Matter Rich Lakes in the Eocene”

By Hugo Olierook 16 June 2022 Applied Geology Chemistry Comments off

Wed 22nd June 2022 @ 12:00 nn, 312.222 and online via Webex (meeting #: 2654 445 7342 and password: JYiaHrxg423)

Abstract:

In this study, continental paleoclimate from the early Cenozoic is reconstructed, when the Earth’s surface experienced a long-term warming trend punctuated by a series of short-lived global warming (hyperthermal) events that culminated in an extended interval of elevated CO2 and extreme warmth, the Early Eocene Climatic Optimum (EECO, 53.26 to 49.14 Ma). The hydrological cycle’s response to climate perturbations is thought to be highly variable, and can promote feedbacks that induce further warming or cooling, thus serving as critical lessons for future warm worlds. However, the response of the hydroclimate regime operating during the EECO is poorly constrained, especially for the mid-to-low latitudes and particularly from continental interior sites.

A multi-proxy approach was adopted, integrating geochemical, organic petrographic, and sedimentological perspectives from organic-rich sediments from the Green River Formation of the Uinta Basin, Utah and the Piceance Basin, Colorado, U.S.A., which were deposited in long-lived, large lakes at ~40ºN. We observed a wide range of organic matter types and distribution, with accumulation of organic matter at the lamination scale controlled by longer term sub-orbital cycles suggesting decadal periodicities in large organic-matter fluxes and associated carbon drawdown. Spatial and temporal variations in salinity conditions were the result of long-term tectonic controls driving the water balance between fresher and brine-rich inputs into the Uinta Basin, increasing ecological stress on biota living in the water column and leading to the cessation of conditions favouring prodigious organic accumulation in the Mahogany Zone, a regionally extensive marker unit. Lastly, hydrogen isotopes from organic molecules indicate that the hydrological cycle operates differently during gradual vs. transient warming events, and that a stable hydrological regime may have supported deep lake development and promoted organic matter preservation allowing for development of this quintessential oil-shale during the early Eocene. These organic-rich lake systems acted as an important negative feedback during the termination of the EECO, sequestering at least ~76 Gt of organic carbon over the ~400 kyr history of the Mahogany Zone.

Short bio:

Amy recently finished her PhD at the University of Southampton, UK, where she used geochemical and sedimentological tools to understand the depositional controls on organic-rich rocks from the Eocene Green River Formation. Prior to this, she focussed on fluvial and aeolian sedimentology for her master’s at Keele University which involved extensive fieldwork in Utah and Colorado, and mapped in Cantabria, N. Spain, where she won the William Smith Geological Society of London award for her 3rd year dissertation. A field geologist by heart, she has moved into multi-proxy approaches, bridging traditional sedimentological methods with biomarkers and stable isotopes, and looks forward to researching extreme fossilisation within concretions at the WA-OIGC under Prof. Kliti Grice.

 

Andrew Langendam (ANSTO) on: “Earth and Environmental Science at the Australian Synchrotron”

By Hugo Olierook 10 May 2022 Applied Geology Comments off

Wed 18th May 2022 @ 12:00 nn, online via Webex (meeting #: 2654 682 4419 and password: 63YkRZ2Agf3)

Abstract:

Techniques offered at the Australian Synchrotron allow for the determination of the elements and phases present in a mineral assemblage, and time resolved structural characterisation. This talk is aimed at researchers that have used the Australian Synchrotron and those interested to learn more about the capabilities the facility can offer Curtin School of Earth and Planetary Sciences. Examples of research conducted on planetary materials, the different ways the Australian Synchrotron can be accessed, and future capabilities that will be offered through the BRIGHT program will be presented.

Short bio:

Andrew Langendam is a Beamline Scientist at the XFM Beamline. He completed his PhD at Monash University in 2016 focusing on the formation and chemical evolution of oxidised planetary bodies in the early Solar System. He has extensive experience organising field expeditions to search for meteorites, having organised the Monash Meteorite Collection Team expeditions between 2009 and 2019. He has also collaborated on a number of searches and projects with the GFO group at Curtin. He has good experience with electron microscope and microprobe techniques alongside X-ray techniques.

 

Stuart Phinn (U. Queensland) on: “Opportunities for working across knowledge systems with earth-observation: working with inter-planetary and indigenous approaches?”

By Hugo Olierook 10 May 2022 Applied Geology Comments off

Tues 22nd March 2022 @ 12:00 nn in 207.222 and online via Webex (meeting #: 2652 672 5983 and password: wxC9n3ngrx8)

Abstract:

Is satellite based, earth- or inter-planetary observations for measuring, monitoring and understanding the earth and other planets, not accurate or use-able unless linked to some sort of “ground knowledge”?

This question and how to address it beyond traditional-disciplinary, -professions and -knowledge systems, is the focus of the presentation. In this context earth observation (EO) is considered an enabling set of technologies and techniques, often linking across disciplines and professions to solve problems, e.g. in education, sciences, governments, industry, and defence. Adoption of EO in government and industry, and broader communities as an accepted source of accurate information for mapping-measuring-monitoring environmental features, requires it is based on: sound science, detailed experiential knowledge of the ground/water/air/planet , collaboration, coordination and communication. EO applications are well developed and adopted for monitoring Australia’s vegetation, meteorology and climate, oceanography and geology, but could be improved. The body of this presentation attempts to answer the question of, how can we improve our environmental understanding, management, custodial roles and intrinsic links by sharing and integrating EO and traditional – indigenous approaches to environmental management, understanding environment and working with it. This would build partnerships using right-way partnerships and science. Using that as a basis, can we take this combined approach to other planets, already being investigated by “planetary observation”? The approach potentially works with knowledge of environmental properties obtained from 10,000’s year of on-country observation and accumulated knowledge, linked to repeated measurement over larger areas from EO.

The approach presented is a starting point, and suggests building partnerships and from areas with extensive indigenous engagement, such as fire management, and potentially water management.

Short bio:

Stuart Phinn is a scientist, educator, and leader who builds and applies methods to measure and understand how our environments are changing at multiple scales (www.rsrc.org.au). He has a strong track record of leading collaborative, multi-disciplinary teams and organisations to deliver quality science that draws upon field-work, satellite-image data, and modelling including: founding directorships of national collaborative research infrastructure (www.tern.org.au) and a world-leading research to operational program that supports government environmental monitoring (www.jrsrp.org.au); and program leadership of industry-driven research (www.eoa.org.au). Stuart’s work provides solutions to support sustainable development and resource use for all levels of government, various industries, and communities.

 

Robert Seggie (Curtin University) on: “Dinoturbation of the Broome Sandstone and a proposed new lithofacies and lithofacies association – SandStone Deformed Dinoturbation (SSDD).”

By Hugo Olierook 24 September 2021 Applied Geology Comments off

Wed 29th September 2021 @ 12:00 nn in 312.222 and online via Webex (meeting #: 2518 636 1317 and password: wmSWYpYU324)

Abstract:

The presence of dinosaur footprints in the Early Cretaceous aged Broome Sandstone of northwestern Western Australia has been known for decades. Previous work has focussed on the discovery of sites, identification of species from the footprints and recording various forms of sedimentary deformation (dinoturbation). Prior global studies into dinoturbation deal with the identification of footprints, species recognition, and morphology, not their sedimentology. This talk reviews the extent and types of dinoturbation observed in the Broome Sandstone by the author as well as observations from engineering core behind outcrops and the key identification criteria of these features in petroleum core. Depositional settings and their relevance to preservation are also reviewed. Dinoturbation varies from individual footprints up to 1.4m in diameter to massive sauropod trackways, wallows and the total destruction of primary sedimentation over whole large outcrops. The sandstone substrate can be fluidised and mobilised to form broad synforms and tight antiforms that may be large enough to be identified on seismic. From this work a new lithofacies association SSDD (SandStone Deformed Dinoturbation) has been characterised and the key identification criteria have been determined to support more effective recognition of dinoturbation in the rock record, including the subsurface.

Short bio:

Robert worked as a petroleum geologist for over 40 years since graduating in geology.  He worked for BHP Petroleum, Oil Company of Australia, BMR (now GA), Santos,  as a consultant, Woodside Energy and has now retired into an Adjunct Professor role at Curtin University together with some consulting.  Robert has been a successful explorer and a development/production geologist. His expertise includes high resolution sequence stratigraphy, structure, hydrodynamics, appraisal co-ordination, and commercial.  For over 20 years Robert focussed on applying high resolution core based sedimentology and sequence stratigraphy to reservoir development and exploration as well as mentoring and improving outcomes for teams.  His current lines of research are into dinoturbation and the global tectonostratigraphy of the Triassic. He has run courses for AAPG, Nautilus, PESA and SPE, has published numerous papers, and presented and chaired at conferences.  He is a member of AAPG,  and PESA and has held executive and editorial positions.

Luc Doucet (Curtin University) on: “Trash to treasure: from dead living things to deep diamonds”

By Hugo Olierook 24 September 2021 Applied Geology Comments off

Wed 15th September 2021 @ 12:00 nn in 312.222 and online via Webex (meeting #: 1704 36 9616 and password: yD3iDJe4cK5)

Abstract:

Rare oceanic diamonds are believed to have a mantle transition zone origin like super-deep continental diamonds. However, oceanic diamonds have a homogeneous and organic-like light carbon isotope signature (δ13C − 28 to − 20‰) instead of the extremely variable organic to lithospheric mantle signature of super-deep continental diamonds (δ13C − 25‰ to + 3.5‰). Here, we show that with rare exceptions, oceanic diamonds and the isotopically lighter cores of super-deep continental diamonds share a common organic δ13C composition reflecting carbon brought down to the transition zone by subduction, whereas the rims of such super-deep continental diamonds have the same δ13C as peridotitic diamonds from the lithospheric mantle. Like lithospheric continental diamonds, almost all the known occurrences of oceanic diamonds are linked to plume-induced large igneous provinces or ocean islands, suggesting a common connection to mantle plumes. We argue that mantle plumes bring the transition zone diamonds to shallower levels, where only those emplaced at the base of the continental lithosphere might grow rims with lithospheric mantle carbon isotope signatures.

Short bio:

Luc comes from Bourg-en-Bresse, a small town in France famously known for its blue-white-red tricoloured (delicious) chickens. In March 2018, he joined the Earth Dynamics Research Group and works with Prof Li to decipher the present-day and past connections between Earth’s mantle, supercontinent and superocean cycles. With the help of other members of the Earth Dynamics Research Group, he reconstructs the geodynamic processes that made the Earth we know today.

Robert Howie (Curtin University) on: “Classrooms in the Cloud”

By Hugo Olierook 24 September 2021 Applied Geology Comments off

Wed 1st September 2021 @ 12:00 nn in 312.222 and online via Webex (meeting #: 1708 27 0571 and password: q5K2VTQKrV7)

Abstract:

As a first-time teacher, Robert went a bit off the beaten track in the delivery of AERO3000 Space Systems Design. In this talk Robert will give a brief overview of the techniques used and lessons learned delivering this unit in a hybrid format: with asynchronous digital lectures and in-person workshops. One of the interesting aspects in the delivery of this unit was the use of Jupyter deployed on a public cloud server to give the students one place for their learning material and the laboratory for exploring the design of spacecraft and space missions. More commonly used for exploring data for research, this free and open source software platform also allows educators to weave together text, equations, video content, interactive diagrams and open-ended coding opportunities into a seamless workbook for students to work through at their own pace. We’ll also briefly touch on how we used Teams to stay in touch, the feedback from students and a few lessons learned along the way, in case you’re thinking about applying some of these delivery methods in your teaching in the future.

Short bio:

Robert completed his PhD at Curtin University in 2019, designing the observatory hardware that powers the Desert Fireball Network (the world’s largest fireball camera network) and has enabled a global expansion in the form of the Global Fireball Observatory. He is currently responsible for Curtin’s half of the FireOPAL space domain awareness partnership with Lockheed Martin Australia and the Space Science and Technology Centre’s teaching in space systems engineering.