The
Assembly of East Gondwana: A Proterozoic Perspective from India
Closepet
Granite (Dharwar Craton)
Supported
by the National Science Foundation EAR04-09101
Project Summary
The
Assembly of
East
Gondwana
:
A Proterozoic Perspective from India
Summary
The
Proterozoic unity of
East Gondwana
is the topic of considerable debate.
Although there are myriad options regarding the exact timing of
East Gondwana
amalgamation, they can be simplified as
follows.
Rogers
(1996) suggested that the
cratonic core of
East Gondwana
was the ‘original’ continent formed
during
the Archean time (
Ur
). Yoshida
and others (2003) argued that
East Gondwana
assembly occurred during the
Mesoproterozoic
culminating with ‘Grenville’ age events assembling various parts of
East Antarctica
to the “
Ur
” protocontinent.
Meert (2003), Fitzsimons (2000) and Powell and Pisarevsky (2002)
argue
that East Gondwana assembly took place in parallel with the assembly of
greater
Gondwana in the Late Neoproterozoic to Early Cambrian time. This
project is
aimed at improving the paleomagnetic database for
East Gondwana
via the acquisition of radiometric ages
for
well-resolved paleomagnetic poles, field tests and additional
paleomagnetic and
geochronologic data from mafic dikes, kimberlites and sedimentary
sequences in
India
.
These
data will then be used to test myriad models of supercontinent assembly
and
dispersal by comparing the results to the published literature and in
conjunction with ongoing projects. The
proposal targets rocks ranging in age from 800 Ma to 2.1 Ga that have
promising
preliminary paleomagnetic data and/or good age control.
Well constrained ages and paleomagnetic poles may also help test
models
of true polar wander and rapid plate motion proposed for Proterozoic
times.
Intellectual
Merit
The
research outlined in this proposal is meant to both complement and
expand our
current knowledge of Proterozoic paleogeography.
Results from the Indian subcontinent can be used in developing
global
paleogeographic models through detailed analysis of existing
paleomagnetic and
geochronologic data from other continents. Paleomagnetic
data can provide evidence for the orientation of geologic features such
as
orogenic belts and dikes used in developing supercontinental
hypotheses. In
addition to published studies, potential correlations are possible due
to
ongoing and currently supported paleomagnetic research in Amazonia (R.
Trindade,
D’Agrella-Filho and NSF post-doctoral fellow E. Tohver, Brazil),
Australia,
South China and Siberia (Z.X. Li, S. Pisarevsky, M. Wingate Tectonics
Special
Research Centre, Australia; David Evans-NSF supported research, USA),
Baltica
(L. Pesonen, S. Mertanen, T. Torsvik, Finland and Norway), Laurentia
(J.
Geissman, New Mexico, S. Harlan, Virginia, D. Evans-NSF supported
research,
USA). New paleomagnetic and
geochronologic data from
India
will add to the
database and allow us to more
easily test the proposed continental configurations.
The paleomagnetic data will also allow us to document drift and
apparent
polar wander rates for
India
that can be
compared to other continents.
Global geodynamic proposals such as true polar wander and
inertial
interchange true polar wander require coverage from all continents in
order to
be critically evaluated.
Broader
Impacts and Personnel
The
University
of
Florida
is committed to enhancing
geologic education in the
USA
through the active
recruitment of
under-represented groups. We will
involve undergraduate students in this research in order to train
future
generations of geologists and have requested funds to support
undergraduate
research projects within the current proposal.
Our work also involves the assistance of Indian colleagues from
the
University
of
Rajasthan
(see attached letter of
support from Manoj Pandit) and M. Santosh
(southern
India
). The work will
also be supported by a
consortium of Indian geologists who are members of the Gondwana
Research Group
(see letter of support from M. Santosh). These
types of collaborative efforts allow investigators in 2nd
and 3rd
world countries to gain exposure to modern scientific methods and
publish in the
geologic literature. Meert has
actively involved foreign colleagues in his work elsewhere in
East Africa
and
Madagascar
. Results from this
project will be shared via
the published literature (i.e. with other scientists); with
undergraduate and
graduate students (via formal and informal departmental seminars) and
with the
general public. PI Meert has been
active in giving talks at all levels of K-12 in
Indiana
and is making efforts to
continue this at
Florida
. PI
Meert is participating in a program called First-year
Florida
aimed at easing the
transition from high school
to the University. One of the
features of this course is helping the students become acquainted with
cutting-edge research projects at
Florida
. In
addition, our K-12 outreach involves summer research initiatives that
bring
underrepresented groups to UF for summer research opportunities.
Project
Participants
Dr.
Joseph G. Meert (Project Director and all around nice guy)
Dr. Manoj K. Pandit
(Project Leader in India and an even nicer guy)
Vimal Pradhan
(Ph.D.
student)
Shawn Malone
(M.Sc. 2007: Now Ph.D. student at the University of Iowa)
Laura Gregory
(M.Sc. 2008: Now Ph.D. student at Oxford University)
Luke Gommerman (B.Sc. student 2007: Now MS student in soil science
University of Florida)
Major Findings & Publications Associated with this proposal:
1.
Pradhan,
V.R., Meert, J.G., Pandit, M.K., Gregory, L.C., Malone, S.J. and
Kamenov, G.D., in
review, India's changing
place in global Neoproterozoic
reconstructions: New Geochronologic constraints on key paleomagnetic
poles from the Dharwar and Aravalli/Bundelkhand cratons, Gondwana Research.
2. Banks, J.C., Sirianni, R.,
Stroud, M., Pradhan, V.R., Newstead, B.,
Gifford, J., Pandit, M.K. and Meert, J.G., The Tectonic evolution of
Peninsular India: A 3.5 billion year odyssey., J. Asian Earth
Sciences,
under review, pdf of
submission.
3.
Gregory, L.C., Meert,
J.G.,
Pandit, M.K. and Pradhan, V., 2009. Paleomagnetic
and geochronologic study of
Malani late phase mafic dikes: implications for the Neoproterozoic
drift history of India
, Precambrian
Research, 170,
13-26. pdf of submission
4.
Pradhan, V.R., Pandit,
M.K. and Meert,
J.G., 2008. A cautionary note on
the age of the paleomagnetic pole obtained from the Harohalli dyke
swarms, Dharwar craton, southern India, in: R.K. Srivastava et
al.
(eds) Indian Dykes: Geochemistry,
Geophysics and Geochronology, Narosa Publishing House,
New Delhi, India, pp. 339-352. . pdf
of submission.z
5.
Malone, S.J., Meert, J.G.,
Pandit, M.K., Kamenov, G.D., Pradhan, V.R. and Tamrat, E.,
2008. Paleomagnetism
and Detrital
zircon geochronology of the Upper Vindhyan
Sequence, Son Valley and Rajasthan, India: A possible downward revision
in the age of the Purana Basins, Precambrian
Research, 164, p. 137-159.
6.
Meert, J.G
and Lieberman, B.S., 2008. The
Neoproterozoic Assembly of
Gondwana and its relationship to the Ediacaran-Cambrian Radiation, Gondwana Research, 14, p. 5-21. pdf
of
submission
7.
Gregory,
L.C., Meert, J.G., Tamrat, E., Malone, S., Pandit, M.K. and Pradhan,
V., 2006. A
paleomagnetic and geochronologic study of the Majhgawan kimberlite,
India
:
Implications for the age of the Upper Vindhyan Supergroup,
Precambrian
Research
,
v. 149, 65-75. pdf
of proofs.
8. Gommerman,
L., Pradhan, V., Meert, J.G., Pandit, M.K. and Gregory, L.C., 2006.
Paleomagnetic study of
Proterozoic dikes in India, GSA Abstracts
w/programs,
paper 143-5. pdf
of abstract.
9. Malone,
S.J., Meert, J.G., Pandit, M.K., Endale, T. and Pradhan, V., 2006.
Magnetostratigraphy and
geochronology of the Vindhaynchal basin, India,
GSA
Abstracts w/program, paper 164-8, pdf
of abstract
10. Gregory,
L.**, Meert, J.G., Pandit, M.K.,
Pradhan, V.*, 2005. Paleomagnetic
study of mafic dikes in India :
implications for supercontinent assembly and
dispersal, GSA Abstracts w/Programs, v37,
303.
11. Malone,
S.J.*, Meert. J.G., Pandit, M.K.,
Tamrat, E.#, Pradhan, V.*, 2005. A paleomagnetic view of the
Vindhyanchal basin,
India
, GSA Abstracts w/Programs, v37,
p. 207.
12. Meert,
J.G., Pandit, M.K., Tamrat, E.#,
Sohl, L., Banerjee, D., Pradhan, V.*, Malone, S.* and Gregory, L.**,
2005.
Preliminary
paleomagnetic results from the Vindhyan Supergroup,
India
, Australia
Supercontinent Meeting.
13. Gommerman,
L., Meert, J.G., Pradhan, V. and Pandit, M.K., Paleomagnetic study of
Proterozoic dikes in India, GSA Abstracts with
programs,
2006
submitted.
14. Malone,
S.J., Meert, J.G., Pradhan, V. and Pandit, M.K., 2006.
Magnetostratigraphy and
geochronology of the Vindhyanchal Basin, India, GSA
Abstracts
w/programs,
submitted.
15. Gregory,
L.C., Meert, J.G., Pandit, M.K., Torsvik, T.H. and Bingen, B., 2006. A
Paleomagnetic and Geochronologic Study of Malani Mafic Dikes in
Northwest India: Implications for the Configuration of Rodinia,
AGU abstracts, 2006.
16. Pradhan,
V., Pandit, M.K. and Meert, J.G., Paleomagnetic and
Geochronologic study
of Proterozoic dikes in Central India, AGU Abstracts, 2006.
