Supervisors: Dr. Ian Hill (Department of Geology, University of Leicester) and Chris Leech (Geomatrix Earth Science Ltd.)
CASE Studentship

Project Summary:
Archaeological excavation is expensive and slow, and also damages the material excavated in an unrecoverable way.  While it is essential for understanding buried historical structures, it must be applied very selectively.  For this reason, geophysical surveys have become increasingly used to guide the positioning of excavations, and magnetic surveys for archaeological purposes are now an accepted standard procedure.  These surveys are themselves costly and time-consuming, and for the majority of any site will be the only evidence of the full spatial extent of the buried structures.  Usually the data are used to construct an image on a surface plan, where the general shape of the image can be interpreted by the archaeologist.
The data collected using modern precise instrumentation are capable of yielding more detailed numerical estimates of the depths to buried structures, and their physical properties.  A number of methods for such interpretation of geophysical data exist and have been widely applied to data from mineral exploration surveys.  Quantitative mathematical models derived from potential field methods have inherent ambiguity due to the nature of the mathematical “inverse problem” of calculating unique source parameters for a particular anomaly.  These problems can be minimised by using suitable constraints supplied by “ground truth” knowledge of the particular location.  The application of mathematical modelling techniques to very-near-surface surveys such as for archaeology is quite rare. 
In this project the existing interpretation techniques will be reviewed, and their suitability for application to the archaeological case assessed.  In particular the ease of application of external constraints will be assessed.  The selected methods will then be trialled on data over known objects, using the University of Leicester test-site and real archaeological sites.  The result will be an improved method for extracting maximum useful archaeological information from the geophysical survey.
Key Project Methodologies and Training Elements:        
The core of the project lies in the development of mathematical modelling techniques for interpretation of magnetic data.  This will involve a range of interpretation techniques, exploiting the measurement of the gradient of the magnetic field, as well as the field strength. Finite-element modelling using a range of constraints is liable to be an important component of the work.  Training in this and relevant computing techniques will be given. 
To produce trial data the Geophysical Test Site at Leicester (managed by Hill) provides the opportunity for controlled field tests.  The supervisors (Hill and Leech) have developed a survey system (GEEP) which facilitates rapid and precise archaeogeophysical surveys.  This system is available at Leicester . 
The supervisors work with archaeologists from English Heritage and other external organisations, as well as within Leicester University .  The student will become involved in archaeological field surveys to become familiar with the applications of the methods to be developed.  Other applications of such methods, such as in environmental and civil engineering surveys will also be considered.
The student will attend the post-graduate training programme in key skills, as well as modules from both the mathematics and earth science departments to develop appropriate specific skills.  
The Student:
He/she will have a broad interest in the application of geophysical methods to investigating the shallow sub-surface, and the enthusiasm to interact with scientists across the range of disciplines involved.  The project will involve extensive geophysical analysis and computation.  It would be appropriate for someone with a first degree in geophysics or physics, a highly numerate geologist, or an applied mathematician with an interest in Earth Sciences. 
Suggested Reading:
An Introduction to Geophysical Exploration.  Kearey, Brooks and Hill. Blackwell, 2003.  (background for non-geophysicists).
P.W. Schmidt and D.A, Clark , 2006.  The magnetic gradient tensor: its properties and uses in source characterisation. The Leading Edge, V25, p75-80. (and other papers in this special issue).
Ian Hill, Tim Grossey, and Chris Leech, 2004.  High-resolution multi-sensor geophysical surveys for near surface applications can be rapid and cost-effective. The Leading Edge, July, pp 684-689
http://www.grams.org.uk/
Website describing the GRAMS project under which the archaeological applications of the GEEP system (then called MSP) were investigated.
About the supervisors:
Ian Hill researches in shallow geophysics using multi-sensor technology to provide high-resolution data-sets on shallow sub-surface deposits.
Chris Leech is a director of Geomatrix Earth Science Ltd and a geophysicist with a long-standing interest in shallow geophysical methods and their interpretation.
To apply: All candidates should apply to the Graduate Office using the Postgraduate Application Form available at http://www.le.ac.uk/graduateoffice/application_form.pdf.  Enquiries to supervisor Dr. Ian Hill, email iah@le.ac.uk.  You are encouraged to apply as early as possible with the final closing date being 13th February 2008; interviews will be held early in March 2008.