Research School of Earth Sciences
Introduction - 2001 in review
The Research School of Earth Sciences (RSES) is engaged in basic research in the physics, chemistry, material properties and environmental conditions of the Earth. As a component of the Australian National University's (ANU) Institute of Advanced Studies (IAS), RSES is expected to both conduct research at the highest international level and take a leadership role in defining new directions of research in geophysics and geochemistry - particularly those which have relevance to the needs and geologic setting of Australia.
During 2001, Professor David Green stepped down after seven distinguished years as Director of RSES. David's tenure as Director was notable for the move towards the study of the Earth's environment, particularly with regard to establishing a geologic baseline for climate change. This initiative is now fully integrated into the School's scientific culture and has substantially reshaped our view of what constitutes the study of the solid Earth. David retired at the end of 2001 to return to the high pressure lab and undertake many long overdue experiments. I greatly admire both what he accomplished during a period of declining support for higher education and the gracious manner with which his goals were realized.
In addition to my transition to the Directorship, several other changes to the School's operation occurred during 2001. Among the most significant was the IAS "buy-in" into the Australian Research Council (ARC) grants scheme, in which a portion of our block grant is transferred permanently to the ARC in return for our scientific staff becoming eligible to complete for ARC funds. Our first foray into contesting ARC funds was highly successful, with 40% of our application receiving support. Our goal is to eventually derive approximately 20% of our total support from both ARC competitions and from Department of Education, Science and Technology (DEST) funds, distributed on the basis of our performance against key research and research training indicators. Because these changes to our funding structure significantly limit our ability to centrally manage the School's research budget, we addressed whether a different model for managing our research enterprise was more appropriate to our new circumstances.
The School chose to devolve budgetary control of most non-infrastructure support with the view that managing those funds as close as practicable to the level of the individual investigator minimizes potential mismatches between research expenditures and grant income. We utilized the four research themes identified in the 1999 Strategic Planning process (see 2000 Annual Report) as umbrella structures to facilitate local budget planning. These four broad disciplinary fields are:
Earth Chemistry (including geochronology and isotope geochemistry, ore genesis, and thermochronology): investigation of the chemical structure and evolution of the Earth and the nature and timing of terrestrial processes.
Earth Materials (including petrophysics, petrochemistry and experimental petrology): study of the chemical and physical properties of earth materials under the conditions of temperature, pressure and stress of the Earth's interior.
Earth Environment (including environmental processes, environmental geochemistry and geochronology and posts funded by IPC environment): elucidation of the chemical and physical processes that operate within and between the Earth's hydrosphere, atmosphere and upper crust, and the establishment of the palaeoclimatic and longer term environmental record.
It is to our clear advantage that we take these immediate steps to take maximum advantage of the opportunities that exist in the new funding environment. While the need to devolve budget authority within the School has been dictated to us by outside events, I anticipated these actions having the effect of further empowering individual investigators to not let the limitations of internal resources suppress their scientific ambitions. My role remains to provide overall academic leadership to the School and undertake strategic planning to maintain the School's position among the world leaders in geophysics and geochemistry research. In that regard, additional reorganization is required.
RSES has a distinguished history of leading the development of experimental and analytical devices in geophysics and geochemistry. While the success of the vast majority of those endeavours reflects the foresight and ingenuity of our scientists, the environment within which those advances took place was to a great degree made possible by our block funding. This system permitted us to undertake high risk endeavours that intrinsically cautious federal grants schemes are generally less able to support. However, erosion of the purchasing power of the block grant through unfunded salary increases and the declining Australian dollar threatens our ability to remain at the forefront of instrument and technique development. Thus, simultaneous with the creation of the four research theme areas, we have chosen to sequester a portion of block grant funding for planning purposes, including seeding of new scientific initiatives, to use as matching funds for external grants, and support original, on-going research efforts that are outside the funding priorities of federal grant schemes. This fund, which will eventually grow to $750k/year will be derived from savings largely realized by external support of technical and fixed term academic posts. Our first initiative is an effort with the Research School of Astronomy and Astrophysics to create a joint institute to study the fundamental nature of planetary systems.
Our academic staff continue to receive international recognition for their outstanding research achievements. Among the many honours bestowed last year (see Major Prizes, Honours and Awards), I note that Professor Ross Griffiths was elected a Fellow of both the Australian Academy of Sciences and the American Geophysical Union. Professor Kurt Lambeck was awarded the Prix International George Lemaître by Louvain University, Belgium. Professors David Green and Malcolm McCulloch both received ISI Citation Laureate Awards for authoring multiple high impact papers. Malcolm has also just learned of his election to AGU Fellowship. Many notable research achievements are described in the body of this report. In describing the research themes of the School, I highlight below just a few of them.
The Environmental Geochemistry and Geochronology Group investigates the long-term interaction between mankind and its environment with a view to guiding our understanding of the past, present and future environments. Of note, they dated the remains of a giant kangaroo at Lake Mungo to be no more than 35,000 years old, whereas nearby aboriginal hearths are at least 41,000 years old. The preliminary conclusion is that at least one giant marsupial appears to have survived long after the arrival of humans on this continent. The implication of this result to the "blitzkrieg" model of human impact on megafaunal extinction is under consideration.
The Environmental Processes Group seek to understand the response of the Earth's surface to physical environments. This past year, they discovered that brief climatic excursions occurred periodically throughout the last 8000 years, suggesting greater global climate instability following the end of the last ice age than previously appreciated.
The Geochronology and Isotope Geochemistry Group focuses on isotopic variations that can be used for dating purposes as well as tracers of large-scale evolutionary processes affecting the Earth. Within that group, two sub-themes have emerged. The Origins subgroup is involved in investigations ranging from the evolution of the Australian continent to the origin of life on Earth. We are following up our recent discovery of evidence of a terrestrial hydrosphere 500 Ma earlier than previously documented. The Thermochronology subgroup recognizes that all significant geophysical processes involve heat flow disturbances and thus seek to understand the tectono-thermal evolution of the lithosphere through use of radiometric systems.
Research in the Geodynamics Group includes the large scale crustal deformation and modelling of tectonic processes, including linkage to surface processes and climate. Among results reported in 2001, the puzzling nature of intracratonic deformation of the Australian continent was successfully modelled as a consequence of horizontal stresses originating at plate boundaries and transmitted into areas of decreased lithospheric strength. This recognition has potentially important implications to our understanding of the effect of the Indo-Asian collision on the Cainozoic evolution of Australia and is the focus of a major consortium of Australian tectonic researchers.
Geophysical Fluid Dynamics is the study of fluid flows and their roles in transporting heat, mass and momentum in the Earth's atmosphere, oceans, crust and deep interior. This past year, laboratory experiments using our rotating table have demonstrated the strong influence of sloping bottom topography on the pattern of upper ocean circulation driven by the atmospheric winds, and we have developed computational methods to study the effect of wind variability on instabilities in ocean currents. We have also discovered new mechanisms by which fresh water input to the oceans at high latitudes can cause oscillations and transitions in the thermohaline circulation that may strongly influence climate variation.
Understanding how orebodies form is vital to the development of mineral exploration models. Research into ore systems is conducted within the Ore Genesis Group, Petrochemistry and Experimental Petrology Group, and the Petrophysics Group. Our efforts are linked with the Department of Geology under the aegis of the Centre for Advanced Studies of Ore Systems. Our experimental work has shown for the first time that the sulfide ores of Broken Hill - the largest known lead-zinc deposit on the planet - must have been partially molten during peak formation. Implications of this discovery could transform our understanding of how giant ore deposits form and lead to refinements in the tools we use to discover them.
The Petrochemistry and Experimental Petrology (P&EP) Group experimentally investigates the physical conditions under which the Earth formed and evolved. This past year, they extended their study of the properties of sulfur in silicate melts by examining very oxidizing conditions, under which the sulfur dissolves as sulfate not sulfide. Implications of this work include understanding sulfur degassing from magmas during major volcanic eruptions, a known cause of global climate modification.
The Petrophysics group research centres on investigation of the physical behaviour of geological materials under controlled laboratory conditions and application of the resulting insights to the structure and processes of the Earth. Using a unique experimental apparatus, we have learned that the partial melting expected beneath mid-ocean ridges results not only in very low seismic velocities, but produces an unusual frequency dependence that could fingerprint molten parts of the overturning upper mantle and thus help us better understand the nature of the Earth's deep interior.
The Seismology and Geomagnetism Group is engaged in investigations of the internal structure of the Earth. This past year saw the development of a new approach to surface wave tomography which permits data from a wide variety of sources to be incorporated resulting in more refined estimates of the Earth's internal structure.
The report that follows describes the results of the School's research programs and publications during 2001 in detail. For this and subsequent years we have abandoned the traditional publication of the Annual Report and instead provide it from the world-wide web base. An abbreviated brochure containing highlights of the full Annual Report will still be published and sent to interested colleagues.