Dear All,
I have received this announcement of a PhD marine geophysics
opportunity in Galway. Please do pass on to anyone who might
be interested and eligible.
Regards,
Sheila Peacock.
-------- Original Message --------
Subject: New PhD position, can you distribute
Date: Wed, 28 Sep 2011 15:05:08 +0100
From: Duffy, Garret <[log in to unmask]>
To: <[log in to unmask]>
Dear Ms Peacock,
We would be grateful if you could distribute the following PhD advertisement
to members of BGA mailing list.
Regards,
*Dr. Garret Duffy*
*______________________*
/Department of Earth and Ocean Sciences/
/National University of Ireland, Galway/
/University Road/
/Galway/
/IRELAND/
/Office: +353 (0)91 492169/
/Fax: +353 (0)91 750533/
The Biogeoscience Group in Earth and Ocean Sciences at NUI Galway
(_www.nuigalway.ie/biogeoscience/griffith/welcome.html_
<http://www.nuigalway.ie/biogeoscience/griffith/welcome.html>) seeks
a PhD student to expand its research in marine geoscience. The research
programme targets national priorities of providing added-value
geoscience research based on databases at the Geological Survey of
Ireland (GSI) and the Marine Institute (MI) in support of the optimum
use of natural resources. The Biogeoscience Group works closely with
the GSI and the MI (based in Galway) and has many existing international
collaborations. The group is now in a position to recruit a person for
a 4-year structured funded PhD programmes in the following area:
*Quantitative Estimation of Seafloor Surface Physical Properties
from Inversions of Multibeam Swath Acoustic Data*
Ship-borne multibeam acoustic data provide information on the
bathymetry and properties of the seafloor surface beneath a
swath that is perpendicular to the track of the vessel and whose
breadth is typically 5 times the water depth. Multibeam surveys
are designed so that every patch of seafloor within the survey area
is ensonified by an acoustic beam, making it possible to produce maps
of the seafloor bathymetry and the strength of the echo (backscatter).
The production of commercial bathymetric maps is standard; however, a
scientifically robust technique to produce physical property maps from
the backscatter data has not yet been developed. Such a technique is of
great industrial interest and is an area of active research.
A new acoustic theory has been developed by Yu, Henrys, Brown, & Marsh
(submitted) that does not impose some of the restrictions on seafloor
physical properties like other backscatter forward models. These
properties include sub-swath spatial scales of the amplitude, correlation
length of seafloor roughness, and acoustic impedance, all of which are
useful for inferring seafloor composition (sediment/rock type), engineering
properties, and benthic habitats. A computer program to realise this theory
has already been benchmarked successfully against a theoretical model using
finite differences. The two techniques have similar precision but the new
theory dramatically reduces the computation time.
The objective of this PhD project is to utilise the outputs from existing
parallelised C++ code to develop practical neural network or non-linear
inversions of observed multibeam acoustic data. There will be opportunities
to work with others in our research group to collect multibeam acoustic and
sediment sampling datasets in coastal environments on the west of Ireland.
These data will be used to develop the practical and robust inversion
algorithms to infer seafloor physical properties. Depending on the skills
base of the successful candidate, there may be opportunities to develop the
theory by incorporating volume scattering mechanisms into the model (e.g.
associated with gas) and poroelastic modifications (e.g. Biot theory) to the
existing theory. The PhD project requires someone from a physics or engineering
background with excellent numerical and computational skills. The successful
candidate will work within a team of about 5 researchers with expertise in
acoustic theory, geophysical inversion, sedimentary processes and oceanography, and
will have the opportunity to attend advanced international training courses
in multibeam acoustic techniques.
For further information and to apply, please send an electronic application
via e-mail to*Dr. Garret Duffy*([log in to unmask]
<mailto:[log in to unmask]>) including a CV with details of previous
degrees awarded and specific courses taken, statement of research goals,
list of publications (if any) and the contact information for 2 referees.
Please use the subject line 'Griffith Award Application Galway' and cc
to [log in to unmask] <mailto:[log in to unmask]>
The closing date for the applications is*17.00 on 28^th October 2011*.
|