Project information
Project aim
Laboratory experiments, using ice from Law Dome ice cores, will replicate the microstructural changes previously identified in fast flowing ice streams. We will systematically measure the effects of deformation on natural polycrystalline ice and compare this to patterns observed in ice cores. Using a fabric analyser microscope we are able to continuously record stress,strain distributions, crystallographic preferred orientation(CPO)and grain size evolution at incremental strain steps up to 50% shortening. Such data sets have the advantage that they allow for the continuous assessment of the relationships between the changing microstructure, CPO and rheology in a material that traditionally has only been experimentally deformed to <20% shortening. Comparisons will also be made to neutron diffraction observations obtained from synthetic ice experimentally deformed at ANSTO. Results will significantly advance our understanding of constraints on strain localization in dynamic ice systems
Project milestones
Summary of the season 2024/25
During 2024/2025 neutron diffraction data from experimentally deformed polycrystalline deuterium ice (D20), which is an analog for water ice was analysed. Three substantial publications on this work have been published and ongoing analyses are still progressing. A public presentation of unpublished data was presented at an Earth Sciences conference in November 2024. Delays in undertaking this work had been caused by COVID restrictions and a medical problem experienced by the Chief Investigator, which have had major impacts and delayed every aspect of our proposed research.
Summary of the season 2022/23
The COVID-19 pandemic had a major impact on every aspect of our proposed research, which was completely disrupted between 2020–22 because of major travel restrictions. In 2022, quarantine and handling restrictions proved a barrier to allowing access to work on AAD ice cores.
This was overcome by accessing the Law Dome ice cores held by the CSIRO Atmospheric Group in Melbourne, which will be used as the basis of complimentary projects currently being undertaken at ANSTO (Lucas Heights, NSW). As a team we were able to publish three significant research papers and others will be produced from experiments that will be undertaken from mid-May to June 2023 on Law Dome ice cores at the Centre for Neutron Scattering at ANSTO.
Summary of the season 2021/22
The COVID-19 pandemic had a major impact on every aspect of our proposed research, which was completely disrupted between 2020–22. With the lockdowns and suspension of international and domestic travel we were not able to go to Hobart to undertake the proposed work or sample the AAD ice cores which are currently stored at Wivenhoe (near Burnie). This was further impacted by changes made at the University of Tasmania and ACE CRC. However, in August 2022, the CI (Wilson) will be travelling to Gothenburg (Sweden) to finalize data that we had acquired from a complimentary project undertaken at ANSTO (Lucas Heights, NSW). As a team we were able to publish two significant research papers and 2+ others will be finalized on this visit to Sweden. Our research goals have never changed and as a result of the ANSTO research we are still proposing to undertaking a full crystallographic investigation of selected ice samples of Law Dome core currently stored in Tasmania during 2023
Summary of the season 2020/21
With the lockdowns and suspension of international and domestic travel we were not able to go to Hobart to undertake the proposed work or sample the AAD ice cores which are currently stored at Wivenhoe (near Burnie). Over the course of 2020/21 the Universities of Monash and Gothenburg (Sweden) had also put in place restrictions that did not allow us to process data that we had acquired from a complimentary project previously undertaken at ANSTO (Lucas Heights, NSW). Despite the significant restrictions as a team we were able to publish one significant research paper on the deformation of ice in a highly cited international journal.
Summary of the season 2019/20
In this project we need to retrieve some ice cores from Wivenhoe and transport them back to Hobart for sample selection and some preliminary experiments and compare these with ice experiments we have undertaken at ANSTO. The CI (Wilson) with co-investigator Mark Peternell in Sweden, were proposing to commence the Tasmanian phase of this work in week 44, i.e 25 to 31 October 2020.
Work on this project was to have been undertaken at the University of Gotenburg, Sweden, in mid-March 2020. However, because of COVID-19 restrictions imposed by Swedish Government, the CI's trip, which had already commenced, had to be cancelled. Similarly, a collaboration with a colleague at University of Mainz had to be suspended and the CI had to return to Australia for self-isolation.
Until international travel restrictions are lifted as a result of the COVID-19 crisis then analysis of the Law Dome ice cores may have to be deferred until 2021. In the meantime, further ice experimental data obtained at ANSTO is being compiled. E.g. new results were published in EPSL (see section 1.3 of this report).