The geology and stratigraphy of the Archipelago Group are reviewed and new data presented to improve understanding. Major lithofacies are bioclastic limestones, bioturbated mottled marlstones, micritic limestones, trace fossil-bearing mudstones, quartzose sandstones and reworked volcanic material of Mio-Pliocene and Pleistocene age. The succession overlies the Pre-Neogene submarine fan turbidites and tectonic melanges of ophiolite derivation and Mithakhari rocks, and is overlain by Quaternary deposits of late Pleistocene-Holocene age. The Neogene sequences were deposited in wave- and current-agitated shallow-marine intertidal and relatively deeper-water subtidal, nearshore and offshore shelfal environments. The existing stratigraphic framework is examined and suggestions made for improvement. © 2017 The Author(s). Published by The Geological Society of London.

P C BANDOPADHYAY

A CARTER

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

The Archipelago Group: current understanding

Geological Society Memoir

This chapter examines the history and distribution of seismicity across the Andaman-Nicobar island arc and Andaman Sea. Fundamental differences between the Andaman section of the subduction zone and the Sumatra-Java section to the south help to explain the nature of the deformation. Magnitudes of displacements varied along-strike from uniform dip-slip on the southern (Sumatran) segment to dip-slip and strike-slip components on the Andaman and Nicobar segment. The Andaman section has a more steeply dipping slab and a thicker sediment cover compared to the Sumatra region where coupling with the overlying plate is stronger. Temporal and spatial patterns of seismicity in the Andaman Sea spreading centre are consistent with normal faulting and c. 25 year cycles of dyke injection are considered responsible for the bulk of the spreading. © 2017 The Author(s). Published by The Geological Society of London.

Seismicity of the Andaman-Nicobar Islands and Andaman Sea

Journal of the Geological Society of India

Honourging the GSI Titans

A note on chemical composition and origin of ferromanganese oxide coated and uncoated pumice samples from Central Indian Ocean Basin

Compositional variation in magma through early neogene in the Northeast Indian Ocean: A testimony from glass shards

Ecology and Conservation of Tropical Marine Faunal Communities

The Late Holocene Foraminifera from Andaman Islands, Andaman Sea, Bay of Bengal

Early Neogene Radiolarian faunal turnover in the northern Indian Ocean: Evidence from Andaman-Nicobar

The archipelago group: Current understanding

Journal	Geological Society Memoir
Publisher	Geological Society of London
ISSN	0435-4052