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Staff Profile

Professor Lewis Ashwal

QualificationsM.S, PhD
Phone 0117176652
Organisational Unit School of Geosciences

Petrology, mineralogy and geochemistry of anorthosite and related rocks; layered mafic intrusions; origin and evolution of planetary crusts; Precambrian geologic history; origin of magmatic ore deposits; role of fluids in igneous and metamorphic processes; meteorites and their parent bodies; abundance and distribution of crustal radioactivity; thermal and petrologic aspects of granulite metamorphism; geology of Madagascar and other Indian Ocean continental fragments, environmental geochemistry, Gondwana assembly and break-up.


  • Metamorphic Petrology, 2nd and 3rd year levels
  • Geochemistry, Honours level, Wits University

Special Activities

Project Scientist, Early Crustal Genesis Project, NASA Office of Space Science and Applications (Administered by the Lunar and Planetary Institute), 1982-1990

Advisor, African National Congress, Office of Science and Technology Policy, Department of Economic Planning, 1993

South African Co-ordinator, France - South Africa Earth Science Co-operation Programme, 1995-1996

Editorial Board, South African Journal of Geology, 1996-1998

Co-editor (with Prof. J.M Barton) of South African Journal of Geology, 1999-

Editorial Board, Journal of African Earth Sciences, 1996-2001

Evaluation Board, Foundation for Research Development, 1996-1997

Committee Member, Earth Sciences Task Group, South African National Antarctic Programme, 1996-2001

Chairman, South African effort to establish a world-class isotope geoscience laboratory (SHRIMP or equivalent instrumentation), 1997-2000

Co-Chairman, Publications Committee, Geological Society of South Africa, 2000-

Post-graduate Coordinator (M.Sc. & Ph.D. students), School of Geosciences, University of the Witwatersrand, 2003-

Disciplinary Committee, School of Geosciences, University of the Witwatersrand, 2003-

Faculty Research Committee, University of the Witwatersrand, 2003-

Executive Committee, School of Geosciences, University of the Witwatersrand, 2004-Current.

Awards and Honors

Academy of Science of South Africa- elected to membership, March, 1998 (one of 114 elected members, of these, 4 are geoscientists)

A1-rated scientist, South African National Research Foundation 1996-2001 (one of 14 such researchers in all sciences, country-wide, one of 3 in geosciences)

Fellow, Geological Society of South Africa, elected March, 2000

Academic colours, awarded by Student Council, Rand Afrik ns University, November, 1996

W.D. Wilson Visiting Fellowship (awarded by Anglo-American Corporation), Rand Afrik ns University, 1990

National Research Council Postdoctoral Fellowship, 1978

New York State Regents Scholarship Incentive Award, 1967



Ashwal, L.D. (1993) Anorthosites, v. 21, Series on “Minerals and Rocks,” Springer-Verlag, New York, Berlin, Heidelberg, 422 pp.

Ashwal, L.D. (1992) Directory of Academic Geoscience Departments in South Africa. Dept. of Geology, Rand Afrik ns Univ., 39 pp., and updated 2nd Edition, 1996..

de Wit, M.J. and Ashwal, L.D., eds. (1997) Greenstone Belts. Oxford Monographs on Geology and Geophysics, No 35, Oxford University Press, 809 pp.

Recent Papers

Owen-Smith, T.M., Ashwal, L.D., Torsvik, T.H., Ganerød, M., Nebel, O., Webb, S.J. and Werner, S. (2013) Seychelles alkaline suite records the culmination of Deccan traps continental flood volcanism.  Lithos, vol. 182-183, pp. 33-47

Ashwal, L.D., Solanki, A.M., Pandit, M.K., Corfu, F., Hendriks, B.W.H., Burke, K. and Torsvik, T.H. (2013) Correlation of Neoproterozoic granitoids from Rajsathan (NW India) and implications for Rodinia and Gondwana. Precambrian Research, vol. 236, pp. 265-281. 

Torsvik, T.H., Amundsen, H., Hartz, E., Corfu, F., Kusznir, N., Gaina, C., Doubrovine, P. Steinberger, B., Ashwal, L.D. and Jamtveit, B. (2013) A Precambrian microcontinent in the Indian Ocean.  Nature Geoscience, vol. 6, pp. 223-227.

Zintwana, M.P., Cawthorn, R.G., Ashwal, L.D., Roelofse, F. and Cronwright, H. (2012) Mercury in the Bushveld Complex, South Africa, and the Skaergaard Intrusion, Greenland.  Chemical Geology, vol. 320-321, pp. 147-155.

Roelofse, F. and Ashwal, L.D. (2012) The lower Main Zone in the Northern Limb of the Bushveld Complex- a >1.3 km sequence of intruded and variably contaminated crystal mushes.  Journal of Petrology, vol. 53, no. 7, pp. 1449-1476 

Cawthorn, R.G., Ellam, R, Ashwal, L.D. and Webb, S.J.. (2012) A clinopyroxenite intrusion from the Pilanesberg Alkaline Province, South Africa, Precambrian Research, vol. 198-199, pp. 25-36.

Ganerød, M., Torsvik, T.H., van Hinsbergen, D.J.J., Gaina, C., Corfu, F., Werner, S., Owen-Smith, T.M., Ashwal, L.D., Webb, S.J. and Hendriks, B.W.H. (2011) Palaeoposition of the Seychelles microcontinent in relation to the Deccan Traps and the Plume Generation Zone in Late Cretaceous-Early Palaeogene time.  In: Van Hinsbergen, D.J.J., Buiter, S.J.H., Torsvik, T.H., Gaina, C. and Webb, S.J. (Eds.) The Formation and Evolution of Africa: A Synopsis of 3.8 Ga of Earth History.  Geological Society of London, Special Publications, v. 357, pp. 229-252

Letts, S., Torsvik, T.H., Webb, S.J. and Ashwal, L.D. (2011) New Palaeoproterozoic palaeomagnetic data from the Kaapvaal Craton, South Africa.  In: Van Hinsbergen, D.J.J., Buiter, S.J.H., Torsvik, T.H., Gaina, C. and Webb, S.J. (Eds.) The Formation and Evolution of Africa: A Synopsis of 3.8 Ga of Earth History.  Geological Society of London, Special Publications, v. 357, pp. 9-26.

Corfu, F., Gerber, M., Andersen, T., Torsvik, T.H. and Ashwal, L.D. (2011) Age and significance of Grenvillian and Silurian orogenic events in the Finnmarkian Caledonides, northern Norway.  Canadian Journal of Earth Sciences, T. Krogh Special Issue on Geochronology, vol. 48, no. 2, pp. 419-440.

Webb, S.J., Ashwal, L.D. and Cawthorn, R.G. (2011) Continuity between eastern and western Bushveld Complex, South Africa, confirmed by xenoliths from kimberlite.  Contributions to Mineralogy and Petrology, vol. 162, pp. 101-107.

Ashwal, L.D. (2010) The temporality of anorthosites.  Canadian Mineralogist, R.F. Emslie Special Issue, vol. 48, part 4, pp. 711-728. 

Torsvik, T.H., Burke, K., Webb, S.J., Ashwal, L.D. and Steinberger, B. (2010) Diamonds sampled from the core-mantle boundary.  Nature, vol. 466, pp. 352-356.

Bybee, G.M., Ashwal, L.D. and Wilson, A.H. (2010) New evidence for a volcanic arc on the western margin of a rifting Rodinia.  Earth and Planetary Science Letters, vol. 293, pp. 42-53.

Roberts, R.J., Corfu, F., Torsvik, T.H., Hetherington, C.J. and Ashwal, L.D. (2010) Alkaline and carbonatitic magmatism coeval with mafic plutonism in the Seiland Igneous Province, Northern Norway: age and palaeotectonic significance.  Journal of the Geological Society of London, v. 167, pp. 71-81.

Letts, S., Torsvik, T.H., Webb, S. and Ashwal, L.D. (2009) Palaeomagnetism of the 2054 Ma Bushveld Complex (South Africa): Implications for emplacement and cooling.  Geophysical Journal International, vol. 179, pp. 850-872.

Cawthorn, R.G. and Ashwal, L.D. (2009) Origin of anorthosite and magnetitite layers in the Bushveld Complex using major element compositions of plagioclase.  Journal of Petrology, vol 50, no. 9, pp. 1607-1637.

Roelofse, F., Ashwal, L.D., Pineda-Vargas, C.A. and Przybylowicz, W.J. (2009) Enigmatic textures developed along plagioclase-augite grain boundaries at the base of the Main Zone, Northern Limb, Bushveld Complex- evidence for late stage melt infiltration into a nearly solidified crystal mush.  South African Journal of Geology, v. 112, pp. 39-46.

Van Lente, B., Ashwal, L.D., Pandit, M.K., Bowring, S.A. and Torsvik, T.H. (2009) Neoproterozoic hydrothermally altered basalts from Rajasthan, northwest India: implications for late Precambrian tectonic evolution of the Aravalli Craton.  Precambrian Research, vol. 170, pp. 202-222.