2016: Year in review

The Palaeoenvironments group was formed in 2017, as a merger between a number of subgroups. Below are the 2016 Year in Review summaries for the research groups:

Ocean and Climate Change

We research a variety of ocean and climate change topics over different timescales, but mostly over the past 1 million years, using marine sediment cores. We perform an array of analyses in wide-ranging collaborations both within ANU and outside, with a strong international outlook. We routinely include probabilistic statistical analyses and quantitative assessments in our analyses results and interpretations. We collaborate with experts in Earth System, ice-sheet, and Glacio-Isostatic Adjustment modelling, and in geochronology and archaeology. Critical topics concern sea-level change, climate sensitivity, monsoon changes, impacts on biogeochemical cycles (especially the carbon cycle), and the processes behind organic-rich sediment deposition. The group is invested in three of the RSES’s new Frontier Themes, namely Ocean & Climate, 21st Century Resources, and Carbon cycle and CO2 sequestration.

In 2016, the group comprised Prof Eelco Rohling, Drs Katharine Grant, Gianluca Marino, Fiona Hibbert and Laura Rodriguez-Sanz, as well as PhD students Jess Amies, Rose Manceau, and Tiah Penny, and Masters student Lynton Hurt. We twice hosted a pair of UK visitors for collaborative work: Drs Felicity Williams and Jenny Stanford, each time for a couple of weeks.

Through 2016, we have achieved about 10 publications, including two in Nature Geoscience, and acceptance on a general-public book on the history of the oceans, to appear in 2017 (Princeton University Press). We presented posters and talks at the major EGU (Vienna, Austria), AGU (San Francisco, USA), and AESC (Adelaide) geoscience conferences, as well as various smaller meetings and workshops that ranged in scope from studies of sea-level and palaeoclimate, to climate–archaeology interactions, geoengineering, and climate modeling. Prof Rohling contributed to lecturing at the Urbino Summerschool of Paleoclimatology (Italy). Our new long-term collaboration was followed up through another extended exchange visit of Dr Rodriguez-Sanz to ETH, Zurich (Switzerland).

Paleo and Environmental Magnetism

New Research Projects

Prof. Andrew Roberts began the 3 year ARC Discovery Project “Unmixing First-Order Reversal Curve (FORC) diagrams for quantitative environmental analysis”.

Prof. Andrew Roberts, Dr David Heslop, Prof. Eelco Rohling, and Dr Xiang Zhao began the one-year ANU Major Equipment Commitee project “Development of new instruments for paleomagnetic research”.

International Visitors

Assoc. Prof. Greig Paterson, Chinese Academy of Sciences, investigating magnetic hysteresis.

Prof. Qingsong Liu, Chinese Academy of Sciences, working on environmental magnetism of sediments.

Dr Zhaoxia Jiang, Chinese Academy of Sciences, working on the magnetic properties of hematite and goethite.

Dr Ping Liu, Chinese Academy of Sciences, working on microtektites in marine sediments.

Mr Wensi Zhang, Chinese Academy of Sciences, working on magnetotactic bacteria.

Dr Edoardo Dallanave, Ludwig-Maximilians-University of Munich, working on magnetostratigraphy.

New Group Members

Yao Qian, Chinese Scholarship Council HDR Student.

Mingkun Li, Key Laboratory of Marginal Sea Geology, Chinese Academy of Sciences.

Dr Yi Wu, South China Sea Institute of Oceanology, Chinese Academy of Sciences.

Meinan Shi, Department of Marine Science, China University of Geosciences.

Guest Lectures

Prof. A. P. Roberts, School of Earth and Space Sciences, Peking University, China

Prof. A. P. Roberts, Invited speaker, 4th Beijing International Symposium on Paleomagnetism and Earth and Planetary Deep Interiors, Beijing, China

Prof. A. P. Roberts, Keynote speaker, International Education Management Conference, Chongqing, China

Dr D. Heslop, School of Earth and Space Sciences, Peking University, China.

Dr D. Heslop, Qingdao National Laboratory for Marine Science and Technology, China

2016 Research Highlight

In recent years the Paleo & Environmental Magnetism group has been investigating mechanisms by which sediments record the Earth’s magnetic field. The presence of magnetic mineral inclusions in igneous rocks and their important contributions to paleomagnetic records are well established, but the presence of such inclusions within detrital particles in sediments and their contribution to the magnetic signals of sediments have been elusive. As part of an ongoing study, we investigated a collection of marine sediments to search for magnetic mineral inclusions using transmission electron microscopic (TEM) and magnetic analyses. TEM observations confirm the abundant occurrence of magnetic nanoparticle inclusions hosted within silicate crystals in marine sediments (Figure 1). We have documented variable inclusion morphologies, including isolated nanoparticles (i.e., octahedra, sub-rounded and irregular shapes), nanoparticle clusters, and dendrites. Silicate minerals are relatively stable against diagenetic alteration in sulphate-reducing marine sedimentary environments, which can, therefore, protect embedded mineral inclusions from dissolution. Our results demonstrate that silicate-hosted magnetic mineral inclusions are an important source of fine-grained magnetic minerals in sediments, which provide important constraints on understanding paleomagnetic and environmental magnetic records of marine sedimentary sequences from a wide range of settings. This work was published in Chang, L., Roberts, A.P., Heslop, D., Hayashida, A., Li, J., Zhao, X., Tian, W., Huang, Q. (2016) Widespread occurrence of silicate-hosted magnetic mineral inclusions in marine sediments and their contribution to paleomagnetic recording. Journal of Geophysical Research, 121, doi:10.1002/2016JB013109.

Figure 1. TEM images of dense magnetic nanoparticle inclusions in silicates for a marine sediment sample from the equatorial Pacific.

Past Climates and Environmental Impacts

Overview. 2016 was another exciting and productive year for the Past Climates & Environmental Impacts group. Our research aims to answer fundamental questions about past climate change and environmental impacts, particularly in the Southern Hemisphere and tropical Australasia. Group members are prominent in the use of geochemical tracers in corals, cave formations, marine cores and ice cores to reconstruct temperature, precipitation and vegetation dynamics, and natural hazards such as volcanic eruptions and great earthquakes. While our over-arching goal is to produce new knowledge about Earth’s environment, our findings provide the scientific basis required for successful adaption to society’s most challenging environmental threats, including anthropogenic climate change.

Members. The group comprises Mike Gagan, Nerilie Abram, Bradley Opdyke, their students, and contributions from numerous colleagues. Dr Gagan’s long-term research program in Indonesia with Prof. Wahyoe Hantoro and Dr Danny Natawidjaja (Indonesian Institute of Sciences) currently provides world-class opportunities for four PhD scholars. Claire Krause (now at Geoscience Australia) was awarded her PhD for work on a 40,000-year history of the Australasian monsoon recorded by speleothems in Sulawesi, Indonesia. Alena Kimbrough submitted her PhD dissertation on the glacial-interglacial history of the Australasian monsoon (also based on Sulawesi speleothems). Jennifer Wurtzel’s PhD (supervised by Dr Abram, based on speleothems from Sumatra) aims to reconstruct post-glacial changes in Indo-Pacific Warm Pool hydroclimates, and Bethany Ellis’ PhD on the Holocene history of the Indian Ocean Dipole (supervised by Dr Abram, using corals from west Java) is well underway. Bob Burne was awarded an M.Phil. for his research on organomineralisation in microbialites from the Yalgorup Lakes, Western Australia. During 2016, Dr Abram also supervised two summer research scholars (Ben Nistor and Sebastian Wong) and two special topics research students (Anson Cheung and Jessica Hargeaves) within the group.

Much of our success is due to the Group’s outstanding Professional Officers, Joe Cali, Joan Cowley and Heather Scott-Gagan, whose dedication and technical capabilities in the Earth Environment Stable Isotope Laboratory make it all possible.

We congratulate Dr Abram on her 2016 promotion to a continuing Academic Level D (Associate Professor) position at RSES.

New research grants. Dr Abram was awarded an ARC Future Fellowship for 2017-2020 to quantify changes in Australia’s rainfall belts over the last millennium. Dr Abram is also a Chief Investigator in the ANU node of the ARC Centre of Excellence for Climate Extremes (led by Prof. Pitman, UNSW) awarded for 2017-2023.

Research highlights. The high international standing of our research achievements was well illustrated by several publications in 2016. Dr Abram led a comprehensive PAGES 2k Consortium synthesis of post-AD 1500 palaeoclimate records (published in Nature) that revealed an early 19th-century onset for industrial-era warming across the oceans and continents. PhD scholar Alena Kimbrough and Dr Gagan had lead co-author roles in a paper in Nature Communications showing links between tropical Pacific hydroclimate modes and century-scale global climate variability over the last 2,000 years. Dr Abram co-authored a paper in Nature Climate Change that assessed recent trends in high-latitude Southern Hemisphere within the broader context of natural climate variability given by palaeoclimate archives.

Dr Opdyke and Jennifer Wurtzel participated in IODP expedition 363 to the Western Pacific Warm Pool. Using material from the cruise, Jennifer will carry out a short research project to assess intervals of Holocene variability in a high resolution marine core collected offshore of Papua New Guinea.

Katie Holder (WA), Brad Opdyke (RSES) and Jennifer Wurtzel (RSES), “The Australian Contingent” on the deck of the JOIDES Resolution for IODP Expedition 363 to the Indo-Pacific Warm pool.

Awards and honours. Jennifer Wurtzel was a finalist for the ANU 3 Minute Thesis competition. Her presentation titled “Reading the Rain in the Rocks” also won the people’s choice award at the ANU Colleges of Science final.

New appointments and service. Dr Abram was an Australian representative for the IPCC scoping meeting for the special report on Climate Change, the Oceans and the Cryosphere, held in Monaco in December 2016. She also continued in 2016 as a Co-Editor-in-Chief for Climate of the Past, and a coordinator for the PAGES 2k project which will enter its 3rd phase in 2017.

Laboratory developments. Dr Abram led a successful ANU Major Equipment Committee grant to install a portable Picarro high-precision water isotope analyser (with new 17O-excess measurement capability) in the RSES Earth Environment Stable Isotope Laboratory.

Water and Regolith Science

The group comprises three academic staff (Penny King, Bradley Pillans and Stewart Fallon), one DECRA fellow (Rachel Wood) and two professional staff (Ulrike Troitzsch and Rebecca Esmay). Our students include Rachel Kirby, Shannon McConachie, Prudence Merriman, Andrew Palm, Christian Renggli and Michael Short. A number of other researchers are associated with our group, including Robert Burne, Patrick de Deckker, Richard Henley, Bear McPhail, Terry Mernagh, Bradley Opdyke and Eva Papp.

Research Highlights

  • New constraints on the composition of dust on Mars (King)
  • Compound-specific dating of rock art (King, Troitzsch)
  • Lake George: a 2.6 Ma sedimentary record of the Quaternary Period (Pillans)
  • Tracking chloride in minerals in cement (Troitzsch)
  • Impact of biomineralization in coralline algae on coral reefs’ Mg-budget (Troitzsch, King)
  • Improving the precision on our understanding of when people first occupied Australia (Wood)
  • Improved methods for radiocarbon dating of teeth (Wood)
  • Intergroup violence amongst early Holocene hunter-gatherers in Kenya (Wood)

Analysing coatings over rock art, western Arnhem Land, NT, Australia.

University Service

  • Deputy Chair, ANU College Access & Equity Committee (King)
  • Chair, RSES Equity & Diversity Committee (King)
  • Chair, RSES Work Health and Safety Committee (Pillans)
  • Organiser, Archaeometry seminar series, Research School of Earth Sciences (Wood)