Geoscience Jobs : Earthworks : PhD Projects: links between mineral and rock composition, deformation and deformation behaviour - Sydney, Australia

The Department of Earth and Planetary Sciences (Macquarie University, Sydney, Australia) invites applicants for the following fully funded 3 PhD positions.

The projects are part of two larger programmes that include 3 PhD students, several honours students, collaborators within the Department and partners in Melbourne, Münster and Toulouse. Both programmes aim to understand the link between mineral and rock composition, deformation and deformation behaviour. In addition, the students will benefit from the ARC National Key Centre for Geochemical Evolution and Metallogeny of Continents (http://www.gemoc.mq.edu.au/) and the ARC Centre of Excellence "Core to Crust Fluid Systems" (http://www.ccfs.mq.edu.au/ ) which bring together experts from across Australia and Europe and provide world-class analytical equipment and expertise.

The students will have the unique opportunity to gain expertise in a wide range of experimental, analytical and numerical techniques.

Project 1: Fundamental link between deformation, fluids and the rates of reactions in minerals: Nature and Experiments (Supervisors: Dr. Piazolo, A/Prof. Daczko)

This exciting project investigates the influence of differential stress rates of reactions during fluid present conditions. Within the project the student will investigate a "natural laboratory" of well exposed high strain zones in Fiordland, New Zealand. The student will analyse samples from the field in detail. In addition, the student will perform experiments using a unique see through pressure and deformation cell at the department. During experiments the fluid composition, fluid pressure and temperature is controlled while deforming the samples at different strain rates. The student will not only observe and quantify the replacement mechanisms but also investigate the sites of change relative to stress concentrations. In addition, the student will record and quantify precisely the formation and evolution of porosity development during the replacement reaction. Depending on the background and interest of the student, the project can also involve numerical simulations using the numerical modelling system ELLE (http://www.microstructure.info/) as well as work together with experts to improve large scale modeling systems such as Underworld (http://www.underworldproject.org/models.html ).

The project outcomes will enhance our understanding of many fundamental geological processes, including metamorphic phase transformations and ore-body formation.

Project 2: Flow characteristics of lower crustal rocks: Field studies and numerical modelling (Supervisors: Dr. Piazolo, Dr. O'Neill)

This varied project aims to improve our knowledge of the flow behaviour, or "rheology", of rocks consisting of different mineral phases. This behaviour controls large scale processes, such as plate tectonics and mountain building. In this project, the student will perform detailed field studies in a selected "natural laboratory" in Fiordland New Zealand, analyse in detail the rocks and geometric relationships and implement results into the numerical modelling system ELLE (http://www.microstructure.info/) as well as work together with experts to improve large scale modeling systems such as Underworld (http://www.underworldproject.org/models.html). In the course of the project the student will gain expertise in field work in high grade rocks, chemical and crystallographic analysis and numerical modeling techniques. Depending on the background and interest of the student, the project may also involve some physical experiments.

The outcomes have a profound significance, as the accuracy of the latest large-scale geodynamic models is dependent on the correct rheological constants.

Project 3: Flow characteristics of lower crustal rocks: In-depth analysis of Xenoliths and experimental studies (Supervisors: Dr. Piazolo, Dr. Afonso)

This varied project aims to improve our knowledge of the flow behaviour, or "rheology", of rocks consisting of different mineral phases. This behaviour controls large scale processes, such as plate tectonics and mountain building. In this project, the student will perform detailed analysis of two suites of lower crustal xenoliths and perform experiments on polymineralic materials. Experiments will be focused on uniaxial deformation experiments using both samples from the field as well as analogue materials such as ice. The student will work together with experts to implement results into large scale modeling systems such as Underworld (http://www.underworldproject.org/models.html). In the course of the project the students will gain expertise in chemical and crystallographic analysis, numerical techniques and different experimental techniques.

The outcomes have a profound significance, as the accuracy of the latest large-scale geodynamic models is dependent on the correct rheological constants.

The scholarships include living stipend and fees, and are for three and a half years. For all projects an international or domestic scholarship is available. Funding is available from February 2012.

Dr Sandra Piazolo (e-mail: sandra.piazolo@mq.edu.au), Department of Earth & Planetary Sciences, Macquarie University, NSW 2109, Australia

Prospective students should send, in the first instance, a cover letter detailing motivation and experience relevant to the research project, a curriculum vitae and an academic course transcript to the principal supervisor.