Dear All,

        A Ph.D. studentship is now available, jointly supervised by Dr Alex
Maltman at the University of Wales, Aberystwyth, and Dr. Al Bolton at the
University of Cardiff, on the fluid-flow behaviour of the Nankai
accretionary margin, utilising samples and data from the recent ODP Leg
190. More detail is given below and repeated in the attached file.

The studentship is funded by the UK Natural Research Council (NERC) and
thus is only available to UK nationals. It would commence from January 15th
2001 onwards. Please contact Alex Maltman if you are interested or have
specific questions. I am at [log in to unmask]; DO NOT REPLY TO GEOTECTONICS!

Thanks,

Alex Maltman






High resolution fluid flow patterns at the Phillipine Sea-Eurasian Plate
margin

Supervisors: Drs Alex Maltman and Alistair Bolton

This project centres on laboratory measurements of permeabilities in
deep-sea cores retrieved during the recent Leg 190 of the Ocean Drilling
Program (ODP). This drilling, together with the forthcoming Leg 196, is
probing deformation and fluid-flow processes at the Nankai Trough, within
the Phillipine Sea-Eurasian Plate convergent margin. The Nankai Trough
accretionary prism is probably the most closely studied in the world; its
basal fault, separating the converging plates, is fundamental to the
earthquake problem that affects SW Japan.

Alex Maltman employed on Leg 190, for the first time in ODP, a gas-probe
permeameter - an instrument capable of assessing permeabilities speedily,
with directionality, and at an unprecedently fine resolution. Nearly a
thousand determinations were made, potentially giving an unprecedented
insight into the hydrogeology of the plate margin. However, the meaning of
these preliminary values and the extent to which they are fully quantitive
remains to be established. And this forms the heart of the project:
designing a programme of laboratory testing to evaluate and assess this
potentially poweful database, in order to build a detailed portrait of the
fluid-flow regime at Nankai.

The student will undertake three steps: 1. digest the shipboard data and
integrate it with relevant core data such as lithology and index physical
properties, in order to derive a qualitative interpretation of the prism
drainage patterns; 2. "back-calibrate" the data against Leg 190 whole-round
cores using now proven, sophisticated permeametry techniques available at
Aberystwyth and data from other laboratories, to give quantitative meaning
to the shipboard, gas-based, values; 3. explore the factors controlling the
differing flow paths in the sediments by employing image analysis and the
new technique of Directional Mercury Intrusion, to assess pore shapes,
sizes, aspect ratios, distributions and directional components. Al Bolton
will be involved throughout but will specifically supervise step 3, at the
University of Cardiff. The studies will complement Alex Maltman's own
research on the deformation structures and their role in prism drainage,
and will link with work on Nankai samples by other, international, teams
who are using a range of approaches and technologies, and with the
logging-while-drilling data expected from Leg 196.

Integrating all these approaches will allow the student establish a new
benchmark in understanding plate-margin hydrodynamics. The dataset will
provide the highest resolution and most comprehensive information on
deformation/fluid-flow dynamics for any convergent margin. The student
would be exposed to truly international collaboration, and would become
familiar with several pioneering methodologies of significance not only in
convergent margin studies but in a whole range of scientific and
technological settings. Moreover, the work is part of the progress towards
a clearer understanding of earthquake genesis and behaviour: the ODP effort
is a precursor study for the planned future drilling at this plate margin
of the "seismogenic window", the depths at which damaging earthquakes
actually originate. Applicants would therefore ideally not only have an
interest in structural geology and enjoy careful laboratory work, but have
a concern for the societal impact of earthquakes.




Dr. Alex Maltman
Institute of Geography and Earth Sciences
University of Wales
Aberystwyth SY23 3DB
Wales
U.K.

Phone 44 01970 622655
Fax 44 01970 622659
email [log in to unmask]