ARC Centre of Excellence for Core to Crust Fluid SystemsAppendix 2: CCFS workplan 2018
1. DEEP-EARTH FLUIDS IN COLLISION ZONES AND CRATONIC ROOTS (TARDIS II)
Activities planned include:
• completing and publishing the remaining studies on the Iranian Tethys
• continuing the detailed analytical work on the Mt Carmel magmatic system
• carrying out analytical work on an analogue from Devonian kimberlites from the Azov area, Ukraine
• publishing work on the Mt Carmel system in at least three papers
• completing and publishing the work on material from Pannonian Basin, Cabo Ortegal and SE Australia
• continuing work on kimberlitic carbonates, and publishing at least one paper.
2. GENESIS, TRANSFER AND FOCUS OF FLUIDS AND METALS
The work plan for 2018 aims to complete the various projects that are still in progress in the three modules. In Module 1, the focus will be on unravelling the genesis of adakites by looking at the natural laboratory provided by Patagonia. In order to provide the necessary constraints to the working hypotheses that are being developed as part of the PhD project of Gonzalo Javier Henriquez, a modelling project will be carried out in parallel in Module 3. The study will examine the style of emplacement of magmas in the crust under a compressive regime and model the evolution of the subducting Nazca plate during the opening of the slab window. In Module 2, we expect to complete the multiple sulfur isotope dataset from the Yilgarn Craton granitoids, with the intent to produce the very first sulfur isotope map of an Archean Craton. It is anticipated that further high-precision TIMS dating, as well as the completion of pending trace element analyses on apatite and zircon crystals from selected porphyry copper systems globally, will elucidate the key constraints on ore genesis in magmatic arcs. It is expected that the work carried out in 2018 will lay the foundations for new collaborations into the future.
3. MODELLING FLUID AND MELT FLOW IN MANTLE AND CRUST
During 2018 the foundation project will see the maturation of many of its numerical approaches and the application to a wide range of CCFS projects. For instance, J.C. Afonso, Beñat Oliveira (PostDoc) and Marti Burcet (new PhD student) will adapt our recently developed Multiphase and Multicomponent Reactive Transport model to simulate and explain the origin and evolution of transcrustal magmatic systems. In addition, we will expand the capabilities of the current numerical platform with both disequilibrium trace-element and isotopic modelling. We foresee immediate applications to a multitude of problems through collaborations across CCFS nodes.
The development of a statistical approach to modelling the transport of melt and crustal production in global mantle convection models will extend into simulations on the interaction of mantle melts, eclogitisation, and lithosphere recycling, planned by C. O’Neill and S. Zhang.
Further seismic imaging combining surface waves and body waves will be performed in NE China to investigate the origin of intraplate volcanism in NE China. This work will be carried out in collaboration with China University of Geosciences (Wuhan) and Southern University of Science and Technology of China.
The experimental laboratory at MQ is closed in the period February to December 2018 for renovations. Some experiments will be carried out in the laboratories of partner institutions (e.g. Australian National University, University of Mainz, China University of Geosciences, Wuhan), whereas other projects will concentrate on data collection and analysis from experiments already run. Current projects include volatile-induced melting of mantle peridotite, carbonate/silicate rock reactions in subduction zones, the deep Earth nitrogen cycle, trace elements in mantle orthopyroxenes, and trace elements in olivine phenocrysts from eastern Australian volcanic rocks.
4. ATMOSPHERIC, ENVIRONMENTAL AND BIOLOGICAL EVOLUTION
Research will continue on established CCFS FP4 projects, including:
A project on the evidence of early life in the Dresser Formation of the North Pole Dome has been funded by an ARC DP (Van Kranendonk, Fiorentini, “A terrestrial hot spring setting for the origin of life? Darwin’s Warm Little Pond revisited”) and a nearly $1M NZD Marsden Fund grant to Prof Kathy Campbell (U Auckland) and CI Van Kranendonk, including a significant component for a new diamond drilling program through the Dresser. Tara Djokic will continue her PhD research into hot spring deposits of the Dresser, and Raphael Baumgartner’s results from the Dresser Formation will be written up as part of his new post-doc position at UNSW, resulting in at least four major papers.
Results from West Greenland fieldwork on the oldest known stromatolites will be written up.
Writing up and further research on the development of complex life in the immediate aftermath of the Great Oxygenation event will continue; with papers from Erica Barlow, Georgia Soares, and Brendan Nomchong (two submitted, three more in progress). Erica is due to complete her PhD this year on the microfossil assemblage of the Turee Creek Group. A new UNSW PhD student, Bonnie Teece (MRes MU), will undertake organic geochemical studies of these complex life-bearing rocks.
Van Kranendonk aims to complete the second edition of Earth’s Oldest Rocks, due for publication in late 2018, and write two major papers on: “The chemistry for Life on Land” (Nature), and “A Planetary Driver of Atmospheric, Biological and Environmental Change through the Precambrian”; a summary of many years work.
The Australian Centre for Astrobiology will co-host Astrobiology Australasia 2018, Rotorua, New Zealand, in collaboration with the New Zealand Astrobiology Network. This meeting will be followed by our “Grand Tour” field trip across Western Australia, from the living stromatolites of Shark Bay back through time to the ancient fossil stromatolites of the Pilbara.
5. AUSTRALIA’S PROTEROZOIC RECORD IN A GLOBAL CONTEXT
Palaeomagnetic analyses and writing up for Yilgarn, northern Kimberley, the Gawler craton and East Antarctica will continue in 2018. Geochronological and geochemical results from the Yilgarn and East Antarctica mafic dykes will also be written up for publication during the year.
6. FLUID REGIMES AND THE COMPOSITION OF EARLY EARTH
Work in Australia will remain focused on Jack Hills. The characterisation of the oldest zircons from the W74 site will continue with the aim of placing tighter constraints on the nature of Earth’s oldest crust. The database acquired in 2017 will be interrogated, and new results on Pb mobility will be prepared for publication. The quartzite locality with ~20% Hadean grains will be re-investigated and detailed characterisation of the new grains undertaken.
The atom probe investigation of lead (Pb) nanospheres in ancient zircons from the Napier Complex, Antarctica, will continue in order to precisely determine their distribution and isotopic composition. Work on the Kemp Land samples has now been extended to include new samples provided by Geoscience Australia.
Another field trip to Labrador will be undertaken in mid-2018 to focus on the distribution of the most ancient gneissic components identified in the 2017 field season.
Work will continue on both lunar rocks and Martian meteorite samples with the aim of constraining the age of the oldest crust and the precise timing of events in the early solar system.
7. PRECAMBRIAN ARCHITECTURE AND CRUSTAL EVOLUTION IN WA
In the eastern Capricorn region, 12 new COPA stations will be in operation until April to fill gaps in the Capricorn deployment. The 40-station Perth Basin Seismic Array will be finished in February 2018. The Ocean Bottom Seismometer deployment is scheduled to end in May 2018. In September 2018, 40 more sites will be deployed during the second phase of the Canning Land project. New seismic models of the crust and sub-crustal lithosphere of the Capricorn Orogen to be submitted for publication include the crustal and shallow upper mantle shear-wave velocity model using ambient noise imaging, the Moho and intra-crustal discontinuity topography mapping using receiver functions and the lithosphere-scale body-wave tomographic model of the Capricorn orogenic mantle. A visiting post-doc will start working on the Perth Basin Seismic array data using ambient noise tomography, receiver function imaging, body wave tomography and auto-correlation. An MSc student from UWA will help in this project. A whole-Yilgarn ambient-noise velocity modelling will start this year, combining existing datasets.