Skip to Main Content
Book Chapter

Provenance of Oligocene Andaman sandstones (Andaman–Nicobar Islands): Ganga–Brahmaputra or Irrawaddy derived?

By
Mara Limonta
Mara Limonta
1
Department of Earth and Environmental Sciences, Laboratory for Provenance Studies, Università di Milano-Bicocca, 20126 Milano, Italy
Search for other works by this author on:
;
Alberto Resentini
Alberto Resentini
1
Department of Earth and Environmental Sciences, Laboratory for Provenance Studies, Università di Milano-Bicocca, 20126 Milano, Italy
Search for other works by this author on:
;
Andrew Carter
Andrew Carter
2
Geological Survey of India, Northern Region, Aliganj, Lucknow, 226 024, India
Search for other works by this author on:
;
Pinaki C. Bandopadhyay
Pinaki C. Bandopadhyay
3
Department of Earth and Planetary Sciences, Birkbeck, University of London, WC1E 7HX, London, UK
Search for other works by this author on:
;
Eduardo Garzanti
Eduardo Garzanti
1
Department of Earth and Environmental Sciences, Laboratory for Provenance Studies, Università di Milano-Bicocca, 20126 Milano, Italy
Search for other works by this author on:
Published:
January 01, 2017

Abstract

Interpretation of the origin of Oligocene Flysch exposed in the Andaman–Nicobar Islands has been the subject of debate. Previous work on the provenance of the Andaman Flysch based on samples from South Andaman has indicated major contributions from Myanmar affected by the India–Asia collision, mixed with subordinate detritus from the nascent Himalayas. This study examines the provenance of a larger suite of samples that extend to North and Middle Andaman islands as well as Great Nicobar Island. Rather monotonous petrographic and heavy-mineral assemblages testify to strong diagenetic imprint, leading to a poorly constrained identification of the sediment source. U–Pb zircon ages provide more robust and diagnostic provenance discrimination between the Myanmar Arc and the growing Himalayan range. Combining petrographic and mineralogical data with detrital zircon U–Pb analyses, we find that most of the Andaman Flysch is dominated by a strong continental-crust signal with only a minor contribution from arc material. Statistical analyses of the data show that most of the samples have a provenance similar to Palaeogene Bengal Fan sediments, although the type section on South Andaman has a closer affinity to the provenance of the modern Irrawaddy.

Supplementary material: Sample location (Table A1), the complete petrographic (Table A2), heavy mineral (Table A3) and U–Pb zircon-age datasets (Table A4) are all available at https://doi.org/10.6084/m9.figshare.c.3634328.v1

You do not currently have access to this article.

Figures & Tables

Contents

Geological Society, London, Memoirs

The Andaman–Nicobar Accretionary Ridge: Geology, Tectonics and Hazards

P. C. Bandopadhyay
P. C. Bandopadhyay
University of Calcutta, India
Search for other works by this author on:
;
A. Carter
A. Carter
Birkbeck University of London, UK
Search for other works by this author on:
Geological Society of London
Volume
47
ISBN electronic:
9781786203007
Publication date:
January 01, 2017

GeoRef

References

Related

Citing Books via

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal