Earth and Environmental Sciences (SEES)

SEESStaffSarah Biejat

Miss Sarah Biejat

Phd Student

School of Earth & Environmental Sciences

Burnaby Building
Burnaby Road
Portsmouth
PO1 3QL

sarah.biejat@port.ac.uk

Profile

My main interests are global geodynamics and tectonic reconstructions. This includes trying to understand the mechanisms and dynamics that drive plate tectonics and the use of a holistic approach to reconstruct the events involved in the formation and break up of supercontinents that has lead us to our present day configuration of continental landmasses. With a background in computer science, I am interested in the use of numerical and 3/4D modelling as visualisation tools for tectonic reconstructions and for mantle processes and their dynamic effect on topography, however without supporting evidence in the rock record, a model is only a model. Hence my interest in my current research project.

PhD Research Project

Detecting the presence of ophiolite, subduction and arc components in detrital accessory minerals.

The principal aim and hypothesis to be tested is can a suite of detrital accessory minerals and their geochemical signatures be used to unequivocally determine the former presence of an active continental margin and thus the presence of plate tectonics?

In many instances where ancient oceans have long closed and orogens are eroded the only remaining evidence that a former plate boundary once existed may lie within small grains of  robust detrital accessory minerals that have survived and remain in the sediments. Recent studies have illustrated how the geochemical signatures of the detrital accessory minerals zircon, rutile and chromite can be used as a powerful provenance and tectonic setting indicators and reveal information about the nature of the host rock and the tectonic environment within which it formed. This research aims to combine the individual potential strengths of these minerals by their simultaneous examination in order to fingerprint the existence of a formerly active convergent margin.

The area of study is primarily focused on sediments proximal to Caledonian ophiolites in the British Isles. The initial samples are from the Unst-Fetlar ophiolite, in the Shetland Isles which represents a well exposed continental margin setting. Sedimentary horizons found within the ophiolite potentially contain material representing arc, ophiolite and subduction processes. The geochemical analysis and radiometric dating of these detrital accessory minerals may also provide further insight into the timing and geodynamic mechanisms involved in the ophiolite emplacement.

Other research interests:

The geodynamic evolution of the Eastern Mediterranean region.

My interest in this area stems from my undergraduate dissertation The geology of Northern Ios, Cyclades, Greece which included 35 days field mapping and my 3rd year independent research project: Detrital records of high pressure metamorphism Ios, Cyclades, Greece, which involved learning heavy mineral separation techniques and using LA-ICPMS for the geochemical analysis of rutile. I also enjoyed 10 days in Cyprus on a field study of the Troodos ophiolite complex and circum- Troodos sedimentary cover.. My understanding of the active tectonics in this region was greatly enhanced by attending international conferences

  •  Fragile Earth GeoMunich 2011. LMU 4-7 September 2011.
  • Tectonic crossroads Evolving Orogens of Eurasia-Africa-Arabia. Middle East Technical University, Ankara Turkey October 4-8, 2010 (including a fieldtrip to the Ankara melange)

Fieldwork:

Total 130 days  including 35 days on a hazard assessment of the stability status of the Northern flank of the Morne aux Diables volcano Dominica, West Indies (Jul-Aug 2009). The project involved geomorphological and geophysical surveying, and identification and assessment of vulnerable features. I was funded for this project by the Royal Geographical Society with IBG. Pre field trip work involved extensive remote sensing using ASTER and Google Earth imagery. Post field trip work involved XRD analysis of rock and clay samples. I developed a website for this project (www.dominicageohazards.org).

Career:

  • 2011    BSc(Hons) Geology First class honours  University of Portsmouth
  • 2001    Sun Certified Java Programmer   Sun Microsystems
  • 1990    BSc(Hons) Computer Science Magna cum laude (2:1) American University of Athens    

 (previously known as The American University of Southeastern Europe)

Teaching:

  • I currently demonstrate for the 1st year Earth Materials course and 2nd year Petrology
  • I assisted on the 2012 2nd year geological mapping fieldtrip to NW Scotland

Grants received:

  • 2009 - RGS with IBG Learning and Leading grant £1000 for Dominica Geohazards Expedition
  • 2010 - University of Texas  $75 conference registration
  • 2010 - Geological Society of London £300 travel grant for Tectonic Crossroads

Professional affiliations:

  •  Candidate Fellow Geological Society of London
  • Member of Geological Society of America
  • Member of American Geophysical Union
  • Member of Mineralogical Society
  • Member of International Association of Mathematical Geosciences
  • RGS Geography ambassador

Publications:

  • Teeuw R., Argyriou N., Biejat S., Dewdney C., Dilmot N., Rust D., Solana C.(2009): Assessing volcano flank instability: Morne aux Diables, Dominica. Procs, conference on “Disaster Risk Reduction for Natural Hazards: Putting Research into Practice”, 4th –6th November 2009, University College, London, UK.
  • Biejat,S. & Willmot Noller,N (2011) Tectonic Crossroads 2010: A melange of Turkish delights.  Geoscientist online special