Chapter 1 Introduction and History of Mapping and Research
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Downloaded from http://mem.lyellcollection.org/ by guest on September 26, 2021 Chapter 1 Introduction and history of mapping and research P. C. BANDOPADHYAY Department of Geology, University of Calcutta, 35 Ballygunge Circular Road, Kolkata-19, India [email protected] Abstract: This chapter examines the history of reconnaissance and geological mapping work on the Andaman and Nicobar islands. To understand early exploration it is necessary to review the driving forces for colonization, including the development of the Andaman Islands as a penal colony for political prisoners. Geological mapping conducted in the colonial era continued after India gained independence in 1947 and expanded in the 1980s to include hydrocarbon and mineral resources. More recent work has placed greater emphasis on supporting field observation data with geochronological, geochemical and petrological analyses. Gold Open Access: This article is published under the terms of the CC-BY 3.0 license. Floating in splendid isolation in the NE Indian Ocean, a curved more complete, integrated and comprehensive treatment of chain of islands, islets and rocks constitute the Andaman and the geology, stratigraphy and tectonics and a first systematic Nicobar archipelago, the central part of the Western Sunda attempt to understand the geomorphology. This first chapter Arc that extends from the outer-arc islands of Sumatra in the outlines the history of the islands and the early exploration south to highlands of the Indo-Burma Ranges (IBR) in the and mapping. north (Fig. 1.1). The north–south-aligned archipelago located at longitude 92–948 E and latitude 6–148 N is flanked by the Bay of Bengal to the west and by the Andaman Sea to the east. History of colonization The Andaman–Nicobar chain stretches for over 700 km with a maximum width of c. 58 km and has a total land area of The tortuous history of the Andaman–Nicobar islands 8249 km2. The islands are an exposed segment of the accre- includes a period of European colonization, serving as a tionary wedge (outer arc) of the Sunda subduction system, penal colony, and a short-lived brutal Japanese occupation where the Indian Plate subducts beneath the Sunda Plate. (1942–45) (Dasgupta 2002; Singh 2006). The first recorded Ongoing uplift of the sediment-dominated accretionary wedge European settlers were from the Danish East India Company has exposed, over a relatively small area, a diverse range of who arrived on the Nicobar Islands on 12 December 1755. rock types associated with the subduction complex (dismem- On 1 January 1756 the Nicobar islands were made a Danish bered ophiolites, volcanic-arc rocks, trench-slope deposits, colony, first named New Denmark (‘The Last Island of the submarine fan turbidites, pelagic sediments and the sediments Savages’) and later (December 1756) Frederick’s Islands of shelf and reef environments), making it an ideal area for (Frederiksøerne). Between 1754 and 1756 the islands were investigating subduction processes. administrated from Tranquebar, the former Danish colony in The region remains tectonically active and experiences fre- what is now a district of the Indian state of Tamil Nadu. The quent arc volcanism and earthquakes. The most recent event, British were not far behind; in the early 1780s captains Ritchie the 26 December 2004 earthquake and tsunami, triggered and Thomas Forrest, a navigator who worked for the British mud eruptions from mud volcanoes on Baratang Island, lava East India Company, surveyed the Andaman islands since eruptions from Barren Island volcano (Fig. 1.2) and metre- they were located along the trade routes of India, Burma and scale subsidence and uplift across the island chain (Fig. 1.3). SE Asia and seen as strategically important. At around this Searle (2006) documented uplift of the coral reefs along the time the British began to establish small settlements on the coast of the Interview Island off the west coast of Middle Andaman islands rather than on the Danish Nicobars. Andaman, and his book Colliding Continents (Searle 2012) Although Britain became the dominant colonial power in the contains a useful summary of the December 2004 Indian region, Denmark did not formally cede its Nicobar territory Ocean tsunami with particular reference to the Andaman until 1868. Islands. One of the earliest and most important British surveys was Books written on the geology of the Andaman and Nicobar instigated by the Governor General of India, Lord Cornwallis, islands tend to be limited in their scope, coverage and depth. who in 1788 dispatched Lieutenant Archibald Blair of the Sharma & Srinivasan (2007) published a book on the geology Bombay Marines to survey the Andaman Islands, instructing of Andaman and Nicobar but only dealt with the Neogene him to raise the Union Flag and to set up a harbour where mer- sequences. The Pictorial Monograph of the Barren Island chant and navy ships might be refreshed and refitted (Blair Volcano by Shanker et al. (2001) is mainly a photographic 1793). Most of the surveying took place between 1789 and documentation of recent and past volcanic eruptions, with a 1790. The detailed instructions provided by Lord Cornwallis limited and inadequate description and discussion of the included mention of visiting the volcano on Barren Island to petrology and origin of the volcano. The Geology and Mineral determine if significant depositions of sulphur (an essential Resources of Andaman-Nicobar Islands published by the ingredient of gunpowder) was present (Phillimore 1945). In Geological Survey of India in 2012 (Miscellaneous Publica- 1789 formal possession was taken by the Indian Government tion No 30, part XX) contains 40 pages of text that only outline (Mouat 1862) and a small squadron of His Majesty’s ships the geology, although it does include a geological map at the under Commodore Cornwallis, brother to the Governor Gene- 1:1 000 000 scale. The aim of this memoir is to provide a ral, visited the islands to extend the survey work, including the From:Bandopadhyay,P.C.&Carter, A. (eds) 2017. The Andaman–Nicobar Accretionary Ridge: Geology, Tectonics and Hazards. Geological Society, London, Memoirs, 47, 1–7. https://doi.org/10.1144/M47.1 # 2017 The Author(s). Published by The Geological Society of London. Publishing disclaimer: www.geolsoc.org.uk/pub_ethics Downloaded from http://mem.lyellcollection.org/ by guest on September 26, 2021 2 P. C. BANDOPADHYAY Fig. 1.1. Location maps of Andaman–Nicobar archipelago and names of individual islands and key places. Downloaded from http://mem.lyellcollection.org/ by guest on September 26, 2021 INTRODUCTION: HISTORY 3 Fig. 1.2. A view of Barren Island from the west. The foreground shows basaltic flows, the centre background a perfectly symmetrical scoria cone with a summit crater associated with Strombolian-type eruptions, and on the left a cliff section of an eroded older stratovolcano consisting of alternating layers of lava and fragmentary ejecta can be seen. harbour at Nanconwry on Nicobar; this led to the Danish Burmese War between the British and Burmese for control of Governor at Tranquebar making a formal protest to the NE India (and to deny the French access to Burmese harbours). British. Blair held charge of the settlement for three years, In the 1830s and 1840s, shipwrecked crews who landed on the first with the establishment of Port Cornwallis on Chatham Andaman were often attacked and killed by the natives and the Island, part of South Andaman. In 1792 it was relocated to islands had a reputation for cannibalism. One headline event North Andaman while keeping the same name, but was aban- took place in 1839 when Johann Wilhelm Helfer, a German doned in 1796. Between 1786 and 1796 the first attempts were doctor and explorer who collected animals and plants for the made to establish a penal colony, but the high death rate led to Indian government, was attacked and killed. Native attacks closure and transfer of the penal role to Malaysia. Over the were commonplace as experienced by the survivors of the next 40 years the British improved the settlement and harbour troopships Runnymede and the Briton that were shipwrecked facilities, and strengthened its hold on the territory. on 12 November 1844 by the same storm among the islands The strategic importance of Port Cornwallis was made clear that form Ritchie’s Archipelago (Fig. 1.1). Survivors (number- in 1824 when it became the rendezvous point for the Bengal and ing in excess of 630) suffered spear and arrow attacks by the Madras troops on their way to Rangoon to join the First natives, although none were reported killed by these actions Fig. 1.3. The mega-thrust earthquakes that created the tidal waves during December 2004 not only destroyed property but also caused permanent submergence leading to a local sea-level change partially submerging houses and temples, Campbell Bay, Great Nicobar Island. Downloaded from http://mem.lyellcollection.org/ by guest on September 26, 2021 4 P. C. BANDOPADHYAY (Journal of the Wreck of the Troop Ships ‘Briton’ and ‘Runny- to form their own nation, although this never materialized. mede’, published by Pelham Richardson in 1845). In 1855 The Andaman Islands formally became part of India in 1950 the government proposed another settlement on the islands, and were declared a union territory in 1956. including a convict colony. The Indian Rebellion of 1857, the Sepoy Mutiny, delayed construction but also gave it an imperative. Early geological exploration After the Indian Rebellion of 1857 was quelled, the large numbers of prisoners were seen as a political threat to the The first recorded geological reports date to 1840 when Dr British establishment; it was therefore considered desirable Helfer visited a few islands of Ritchie’s Archipelago (reported that prisoners be removed from the Indian subcontinent. In in Oldham 1885).