Document 254582

Research Frontiers
Programme 2006
Pre-Proposal Cover Sheet
PROJECT TITLE (Max. 30 words)
PICASSO: Program to Investigate Convective Alboran Sea System Overturn
Primary Domain Geosciences
Secondary Domain Physics
PRINCIPAL INVESTIGATOR DETAILS AND CONTACT INFORMATION
Title
Professor
Year Ph.D. (or equiv):
1977
Alan G Jones
Name
School of Cosmic Physics
Department
Gender:
Male
Institution
Dublin Institute for Advanced Studies
5 Merrion Square, Dublin 2
3rd level Address
Year Faculty Appointment: 2003
alan@cp.dias.ie
01-662-1333
E-mail
Telephone
01-662-1333
01-662-1477
Dept. Telephone No.
Fax:
Scientific Abstract (max 100 words)
Competing models of lithospheric recycling are poorly distinguished based on extant geoscientific data.
Within the plate tectonic paradigm lithospheric recycling is driven by subduction at active plate margins.
However, evidence is mounting that non-plate processes, such as lithospheric delamination or convective
mantle overturn, are significant. These models will be examined in arguably the world’s most appropriate
natural laboratory, the western Mediterranean, by a consortium comprising of a multi-disciplinary team of
scientists from Europe, the U.S. and Morocco. This proposal is for involvement by Irish-based scientists in
this major geoscientific endeavour, accepted as a pilot project for EuroArray and Topo-Europe.
Project Abstract (max 100 words, written for a lay audience)
How does the Earth work? This question is at the heart of the project, which is to test hypotheses for how
material is recycled from the surface back into the mantle. The plate tectonic model, a wonderful descriptor
of our planet, incorporates recycling through subduction of rocks at active plate margins. However, there is
growing evidence that material can be recycled into the mantle at locations away from plate margins, thus
other processes must be operating. A large international team of scientists, from Europe, USA and
Morocco, will tackle this geoscientific question through studying the western Mediterranean and
surrounding landmasses.
What is the question that this proposal addresses?
A consortium of Earth scientists from Europe, the U.S., and Morocco, including the PI
(Jones) at DIAS, is proposing a collaborative, international, multi-disciplinary project to
various funding agencies for studying the ongoing lithospheric delamination event occurring
in the western Mediterranean beneath the Betic-Rif-Alboran Sea-Atlas mountain system of
southern Spain and northern Morocco. This project, organized by Spanish (R. Carbonnell,
Barcelona) and U.S. (A. Levander, Rice) investigators, is named PICASSO for Program to
Investigate Convective Alboran Sea System Overturn, and has been selected as a pilot
program for the nascent EuroArray and Topo-Europe programs. A project web page gives
more details of the PICASSO proposal, including information from the workshop held in
June, 2005 (wija.ija.csic.es/gt/rc/HTML/indexPICASSO.html).
Delamination, convective overturn, and lithospheric Rayleigh-Taylor instability are general
terms describing a phenomenon of the orogenic cycle. The three terms refer to a process in
which a substantial part of an orogenic lithosphere, often including the lowermost crust, is
removed by negative buoyancy forces exposing the lower crust to asthenospheric mantle and
injection of mantle derived basaltic melts. For the sake of simplicity the term “delamination”
will be used to refer to all three processes. Delamination can cause widespread
metamorphism and crustal anatexsis, complete remelting of parts of the existing crust, and
often extreme uplift and crustal extension. The delaminated lithosphere is returned to the
mantle in a non subduction process, making it part of Earth’s larger convective cycle, but one
that is not directly part of the plate tectonic cycle. Delamination-like processes are attributed
to have caused the western U.S. Basin and Range extensional province, to have caused the
uplift of the southern Sierra Nevada batholith and other localized uplifts in the western U.S.
such as the Colorado Plateau and parts of the Rockies such as the Willawas, OR, and to be
ongoing beneath parts of the Altiplano-Puna system and the Tibetan Plateau. Delamination
events are thus associated with all of Earth’s great orogenic plateaus, and are possibly
associated with most orogenic events, both ancient and modern.
Figure 1: Tecronic map of western Mediterranean with survey area in box
The orogenic belt of study (Fig. 1), consisting of the compressional belts of southern Spain
and northern Morocco, and the extensional Alboran Sea, is thought to be the site of a
modern, ongoing delamination event. Evidence supporting this comes from seismicity
patterns that show seismic activity extending from the base of the crust to the mantle
transition zone, limited teleseismic tomography which has outlined a high velocity
lithospheric slab in part decoupled from the overlying mountain belt-extensional basin
system, observation of low seismic velocities at the base of the crust beneath much of the
region indicative of rising asthenosphere replacing the delaminating lithosphere, and basaltic
and exotic volcanism in and around the Alboran Sea associated with decompression melting
of the rising asthenospheric mantle. This system provides us with a geographically compact
region in which to study a wide variety of the geophysical, geodynamic, and geochemical
processes associated with delamination. Other major geoscientific questions will be
addressed at the same time, such as the reason for the elevation of central Spain and for the
lack of a mantle root beneath the Atlas mountains. Moreover, unlike the Tibetan or
Altiplano-Puna systems, the region offers both a controlled experiment in that delamination
is thought to be the principal process operative in the last 5 Myr, and a well developed
infrastructure for fielding a sophisticated collaborative Earth science experiment.
Why is this problem significant?
Four competing models are proposed for the Alboran Sea anomaly; retreating subduction,
slab break-off, delamination (sensu stricto), and convective removal. The first two describe
plate tectonic processes, whereas the latter two are non-plate processes. Despite prior studies,
the extant data are insufficient to discriminate between these models, thus even in this
controlled natural laboratory we are unable to ascertain the nature of geodynamic processes
that are shaping our Earth’s surface.
The motivation is to study the lithospheric processes that are affecting the area: if there is a
place in the world were delamination is an active process, this is probably it. The way to
address the proposed topic with the highest probability of success is a large-scale, multidisciplinary research program that includes structural geology, geodynamic modelling,
magnetotellurics, gravity and multi-scale, multi-seismic experiments. These acquisition
experiments would be addressed to constrain the crustal and upper mantle structure. The
broad interest in the main target of this research program makes it an excellent candidate for
the EuroArray pilot experiment, and for a Topo-Europe pilot project.
How will the question be addressed? (i.e. Briefly describe the experimental and/or
theoretical methods that you plan to use.)
The project will include an extensive array of portable broadband land and marine
seismograph and magnetotelluric stations extending from central Spain to the Sahara desert,
and from the Atlantic Ocean through the Alboran Sea into the Mediterranean Sea,
complementing the permanent seismograph networks in the western Mediterranean countries.
Other components of the project will include land and marine active seismic investigations,
petrology/geochemistry, structural geology, GPS, and geodynamic modelling. The
PICASSO consortium is seeking funding from a variety of sources, including the U.S.
National Science Foundation, the European Science Foundation under the aegis of
EuroArray/Topo-Europe, and the individual science foundations of Europe, including this
proposal to Science Foundation Ireland for Irish participation. Seismological instrumentation
will be provided by the IRIS/PASSCAL instrumentation facility, the European
instrumentation facility at the GFZ, and from individual institutions and national
governments, including DIAS. Magnetotelluric leadership and instrumentation will be
provided principally by DIAS and the University of Barcelona, with other European and U.S.
institutions taking part.
An approximate experimental plan for the
profiling component is shown in Fig. 2.
This plan is subject to change depending on
the successes of the proposals to the
various funding agencies. In addition to
these profiles, under the auspices of
EuroArray there will be seismic and
magnetotelluric acquisition on land, with a
50x50 km grid, within the whole area of
study outlined in Fig. 1. Additional oceanbottom seismic and magnetotelluric
measurements are expected to be proposed
by appropriate groups in Europe and the
U.S.
To a large extend the magnetotelluric and
seismic acquisition do not need to run
concurrently, and indeed there are
compelling logistical and scientific
arguments for having the magnetotelluric
acquisition in advance of the seismic work.
The fieldwork for the magnetotelluric
component funded by SFI would take place
in 2007 and 2008, with the two (or three)
DIAS-based students who would be
supported by the project funding starting
their studies in September 2006.
Figure 2: PICASSO proposed profiles
Although the acquisition methodologies for all of the geoscientific subdisciplines are wellestablished, this project will provide an opportunity for innovation through the integration of
all of the data into a coherent, cogent, process description of the whole region.
A partial list of the institutions, with key individuals, that have thus far indicated their desire
to take part in PICASSO (for a more complete list, please see
wija.ija.csic.es/gt/rc/HTML/ParticipantsPICASSO.html):
CSIC Earth Sci. Barcelona:
DIAS:
GFZ Potsdam:
Rice University:
UCSD/SDSC/GEON:
U. Barcelona
U. Copenhagen:
U. Leeds
U. Leicester:
U. Oregon:
Utrecht U.
R. Carbonnell (PICASSO lead co-PI), J. Gallart
A.G. Jones (EuroArray lead co-PI), X. Garcia
R. Kind
A. Levander (PICASSO lead co-PI), C-T.A. Lee, A.
Lenardic, F. Niu
D. Seber
J. Ledo, A. Marcuello, J. Pous, P. Queralt
H. Thybo (EuroArray lead co-PI)
G. Houseman
P. Maguire (EuroArray lead co-PI)
G. Humphreys, D. Toomey
W. Spakman
Vrije U. Amsterdam
S. Cloetingh (Topo-Europe lead PI)
What is the recent record of accomplishment in research that argues for project
success?
The PI (Jones) has a well-established track record for leading large national and international
multi-institutional magnetotelluric experiments, principally through his activities in
Lithoprobe, INDEPTH, and most recently as project leader for SAMTEX (Southern African
Magnetotelluric Experiment), and bringing them to fruition. He has over 100 papers
published in the international literature, of which many relate to imaging crustal-scale
orogenic processes and integrating magnetotelluric data with data from the other geosciences.
Jones was a key figure in the internationally-renowned Lithoprobe programme under which
multi-disciplinary geoscientific studies of Canada were conducted over the last 20 years. His
experience at leading such projects will prove valuable for the PICASSO project.
Since moving to DIAS in 2004 Jones instigated, and together with Professors H. Thybo (U.
Copenhagen) and P. Maguire (U. Leicester) initiated, thinking within Europe about the
necessity for a pan-European geoscience programme of study for understanding Europe’s
formation and evolution. This project is named EuroArray (www.euroarray.org), and
presentations have been given at European (EGU) and international (AGU, IGC)
conferences. EuroArray is now a component of Topo-Europe (www.geo.vu.nl/users/topo/),
led by Professor S. Cloetingh (Amsterdam), for the integrated study of Europe from outer
space to the inner core with particular reference to topography and societal implications of
short and long term climactic and geodynamic change. PICASSO has been accepted as a
pilot project under EuroArray and Topo-Europe auspices, and Jones is on the PICASSO
International Steering Committee.
Also, since 2004 Jones has built an MT group that is the envy of many, with six scientists
and four post-graduate Ph.D. students studying MT from theory through processing/analysis
to modelling to interpretation. Through Jones, DIAS has a formal memorandum of
understanding with the University of Barcelona, home to another significant and active MT
group. Together, these two groups will form the nexus of the MT work on PICASSO.
What is the value of this research to the people of Ireland?
Understanding how the Earth works is fundamental to our very existence on our planet. One
of the fundamental tectonic processes that shapes the Earth is recycling of material from the
mantle to the surface and back into the mantle. Unless and until this process is fully
understood where it can be actively observed in action, we have no hope of ever explaining
the past tectonic history of the Earth. In particular, the tectonic history of Ireland, with its
major orogenic episodes, especially the closure of the Iapetus Ocean, will only be correctly
known when we are able to understand and explain current tectonism.
Secondly, PICASSO is in itself a highly worthwhile international project that Ireland should
be a part of. However, it is also the pilot project for EuroArray and Topo-Europe, both of
which are major proposals for pan-European geoscience for the next decade. Ireland should
not miss out on the opportunity to be part of, indeed to play a leading role, in both of these.
Finally, under SFI funding for PICASSO at least two, and possibly three, Ph.D.-level
graduate students will be supported and trained within a large project that offers broad scale
opportunities for undertaking holistic geoscience to tackle a major geoscientific problem.
SFI Short Curriculum Vitae (2006): Alan G. Jones (family name: Menzel-Jones)
Education:
B.Sc. 1969-1972
Physics
University of Nottingham
M.Sc. 1972-1973
Applied Geophysics University of Birmingham
Ph.D. 1973-1977
Geophysics
University of Edinburgh
Employment – Permanent:
University of Münster, Germany
1977 - 1981 Scientific Associate (BAT-IIa)
University of Toronto, Canada
1982 - 1983 Research Associate
Geological Survey of Canada
1984 - 2003 Res. Scientist, Senior Res. Scientist
Dublin Inst. Advanced Studies
2003 - present Senior Professor, Head of Geophys.
Employment – Honorary:
Syracuse University, New York
1996 - present
Adjunct Professor
Queen’s University, Kingston
1996 - present
Adjunct Professor
Trinity College, Dublin
2004 - present
Visiting Professor
National University Ireland, Galway 2004 - present
Adjunct Professor
Geological Survey of Canada
2005 - present
Visiting Scientist
Training (last ten years)
M.Sc.: G. McNeice (1997, Memorial U. Newfoundland. Now with Geosystem srl.), K. Solon
(2001, Syracuse U. Now with Exxon), J. Spratt (2003, Syracuse U. Now at DIAS), S.
Evans (2003, Queen’s U. Now with DeBeers)
Ph.D: Max Moorkamp (current, DIAS), Mark Hamilton (current, DIAS), Anna Avdeeva
(current, DIAS), Marion Miensopust (current, DIAS)
Publications in international literature: 107 (as of 25 September, 2005)
Full list can be viewed at: www.geophysics.dias.ie/~ajones/papers/publications.html
Relevant Publications (PICASSO pre-proposal)
1.
Jones, A.G., 1998. Waves of the future: Superior inferences from collocated seismic
and electromagnetic experiments. Tectonophys., 286, 273-298. (Invited review paper)
2.
Jones, A.G., et al., 2002. Magnetotelluric and teleseismic study across the Snowbird
Tectonic Zone, Canadian Shield: A Neoarchean mantle suture? Geophys. Res. Lett., 29
(17), doi: 10.1029/2002GL015359.
3.
Jones, A.G., J. Ledo and I.J. Ferguson, 2005. Electromagnetic images of the TransHudson orogen: The North American Central Plains anomaly revealed. Can. J. Earth
Sci., 42, 457-478.
4.
Solon, K., A.G. Jones, et al., 2005. Structure of the crust in the vicinity of the
Banggong-Nujiang suture central Tibet from INDEPTH magnetotelluric data. J.
Geophys. Res., accepted, 11 April, 2005.
5.
Jones, A.G., et al., 2005. The electrical resistivity structure of Archean to Tertiary
lithosphere along 3,200 km of SNORCLE profiles, northwestern Canada. Can. J. Earth
Sci., accepted, 13 July, 2005.
Grants/awards/funding held (last five years):
1.
SAMTEX: SFI, Ireland, 2005-2008. Award €172,000 (PI)
2.
ISLE-MT: IRCSET, Ireland, 2003-2006. Award €171,645 (PI)
3.
Slave2Bear: NWT Government, Canada, 2004. Total of C$250,000 (Co-PI. PI: V.
Jackson). Subcontract award to A.G. Jones ~C$70,000.
4.
Kaapvaal: Nat. Science Foundation, USA, 2003-2005. Total of US$522,411 (Co-PI).
5.
INDEPTH4: Nat. Science Foundation, USA, 2004-2007. Total of US$522,411 (Co-PI).
6.
Central Baffin: Internal GSC funding, 2001-2003. Total of C$2,540,000 (PI: M. StOnge). Amount controlled by A.G. Jones C$202,000.
7.
Slave Lakes: Nat. Science Foundation, USA, 1999-2002. Total of US$384,643 (Co-PI).
8.
SNORCLE: Lithoprobe, Canada, 1996-2000. Total for MT component in excess of
C$500,000 (PI).