Skip to main content

Toba Ash on the Indian Subcontinent and Its Implications for Correlation of Late Pleistocene Alluvium

  • Subhrangsu Kanta Acharyya (a1) (a2) and Prabir Kumar Basu (a1) (a3)

The Toba ash occurs extensively in the Indian subcontinent and marks a ca. 74,000-yr-old event. In the Bay of Bengal and Indian Ocean it is about 10 cm thick, whereas in several alluvial basins, it is usually 1-3 m thick. The latter occurs in a partly reworked state but as nearly chemically pure first-cycle sediments, The ash has a broad northwesterly dispersal pattern. Samples of ash from the Indian subcontinent compare closely with the youngest (74,000 yr B.P.) Toba Tuff and the deep-sea Toba ash in bulk chemical composition, REE signature, and bubble-wall shard morphology. However, a more proximally located and thicker (2-5 m) ash-bed, from the alluvial basins in the gneissic area and close to east coast, has a lower magnitude negative Eu anomaly, possibly because of minor contamination by feldspathic silt. Quaternary sediments in the central Narmada and middle Son basins contain rich late and middle Pleistocene mammalian and cultural records. Based on the presence of the ash layer marker and stratigraphic relations, late Pleistocene sediments within the subcontinent can be correlated with those from central India and the deep sea.

Hide All
Anonymous, (1989). Late Quaternary ash bed in the Barakar River section, Bihar. News Geological Survey of India, Centra! Headquarters 20(1), 18.
Anonymous, (1990). Late Quaternary ash bed and Acheulian imple-ments from Orissa—The implication. News Geological Survey of India, Eastern Region 10(1), 7.
Anonymous, (1991). Volcanic ash in the Quaternary formations Sagileru valley. News Geological Survey of India, Southern Region 9(2), 9.
Basu, P. K., and Biswas, S. (1991). Quaternary ash bed from eastern India. In “A decade of scanning electron microscopy in GSI”, Geological Survey of India, Special Publication 16, 6568.
Basu, P. K. Biswas, S., and Acharyya, S. K. (1987). Late Quaternary ash beds from Son and Narmada basins, Madhya Pradesh. Indian Minerals 41, 6672.
Biswas, S., and Dassarma, D. C. (1986). Stratigraphy of the Quaternary alluvial deposits of the Central Narmada valley in Madhya Pradesh, India. Proceeding of the XI Indian Colloquium on Micropalaeontol-ogy and Stratigraphy, Bulletin Geological Mining Mettalurgical Society of India 54, 1827.
Biswas, S. Basu, P. K., and Sarkar, G. P. (1989). Biostratigraphy of the Quaternary alluvial sediments in the Central Narmada Basin and the Middle Son Basin in Eastern Madhya Pradesh. Unpublished report. Geological Survey of India 38P.
Chesner, C. A. (1985). Geochemistry of the Toba ignimbrites: Implications on silicic magma bodies, outflow patterns, and caldera collapse. EOS (American Geophysical Union Transactions) 66, 1141.
Chesner, C. A. Rose, W. I. Drake, A. D. R., and Westgate, J. A. (1991). Eruptive history of Earth’s largest Quaternary caldera (Toba Indonesia) clarified. Geology, 19, 200203.
Clark, J. D., and Sharma, G. R. (1983). A discussion of preliminary results and assessment of future research potential. In “Palaeoenvi-ronment and Prehistory in the Middle Son Valley” (G. R., Sharma and J. D., Clark, Eds.), pp. 261273. Department of Ancient History, Culture and Archaeology, Allahabad University A. H. Wheeler & Co., Allahabad.
Dehn, J. Farrel, J. W., and Schmincke, H.-U. (1991). Neogene Teph-rochronology from site 758 on northern Ninety east Ridge: Indonesian arc volcanism of the past 5 ma. Proceedings of the Ocean Drilling Programme, Scientific Results 121, 273295.
Devdas, V., and Meshram, S. N. (1991). Search for Quaternary ash bed in the Quaternary basins of Orissa. Records Geological Survey of India 124(3), 4042.
Korisettar, R. Venkatesan, T. R. Misra, S. Rajaguru, S. N. Somaya-julu, B. L. K. Tandon, S. K. Gogte, V. D. Ganjoo, R. K., and Kale, V. S. (1989). Discovery of a tephra bed in the Quaternary alluvial sediments of Pune district (Maharashtra). Peninsular India. Current Science 58, 564567.
Mandal, D. (1983). A note on the radiocarbon dates from the Middle Son valley. In ‘“Palaeonvironment and Prehistory in the Middle Son valley” (G. R., Sharma and J. D., Clark, Eds.), Appendix B, pp. 285289. Department of Ancient History, Culture & Archaeology, Allahabad University A. H. Wheeler & Co., Allahabad.
Ninkovitch, D. Shakleton, N. I. Obradovich, J. D., and Izett, G. (1978). K-Ar age of the late Pleistocene eruption of Toba, north Sumatra. Nature 276, 574577.
North American Commission on Stratigraphic Nomenclature (NACSN) (1983). North American Stratigraphic Code. Bulletin American Association of Petroleum Geologists 67, 841875.
Poddar, B. C Verma, K. K. Tewari, M. P. Rahate, D. N. Khan, A. A. Sonakia, A. Biswas, S. Nandi, A. Krishna, S. G. Dubey, U. S. Bhai, H. Y. Fahim, M., and Sitaramaiah, Y. (1991). Narmada valley project. Records Geological Survey of India 124(6), 245246.
Rose, W. I., and Chesner, C. A. (1987). Dispersal of ash in the great Toba eruption, 75 ka. Geology 15, 913917.
Rose, W. I., and Chesner, C. A. (1990). Worldwide dispersal of ash and gases from earth’s largest known eruption: Toba, Sumatra, 75 ka. Palaeogeography. Palaeoclimatology, Palaeoecoiogy 89, 269275.
Sonakia, A. (1984). The skullcap of early man and associated mammalian fauna from Narmada valley alluvium. Hoshangabad area, Mad-hya Pradesh (India). Records of the Geological Survey of India 113(6), 159172.
Sparks, R. S. J., and Wilson, L. (1976). A model for the formation of ignimbrite by gravitational column collapse. Journal of the Geological Society of London 132, 441451.
Woods, A. W., and Wohletz, K. (1991). Dimensions and dynamics of co-ignimbrite eruption columns. Nature 350, 225227.
Williams, M. A. J., and Royce, K. (1982). Quaternary geology of the Middle Son valley, North Central India: Implications for prehistoric Archaeology. Palaeogeography, Palaeoclimatology, and Palaeoecoiogy 38, 139162.
Williams, M. A. J., and Royce, K. (1983). Alluvial history of the Middle Son valley, North Central India. In “Palaeoenvironment and prehistory in the Middle Son valley” (Sharma, G. R. and Clark, J. D., Eds.), pp. 921, Department of Ancient History, Culture & Archaeology, Allahabad University A. H. Wheeler & Co., Allahabad.
Williams, M. A. J., and Clarke, M. F. (1984). Late Quaternary environments in north-central India. Nature 308, 633635.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Quaternary Research
  • ISSN: 0033-5894
  • EISSN: 1096-0287
  • URL: /core/journals/quaternary-research
Please enter your name
Please enter a valid email address
Who would you like to send this to? *


Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed