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

                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.