THE MALDIVES PROJECT IN THE INDIAN OCEAN

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THE MALDIVES PROJECT IN THE INDIAN OCEAN
MULTIPLE INTERACTING PARAMETERS
Nils-Axel Mörner . President (1999-2003) of
the INQUA Commission on Sea Level Changes
and Coastal Evolution Leader of the Maldives
Project (from 2000 on) an international
research project among sea level
specialists Co-ordinator of the INTAS project on
Geomagnetism and Climate (1998-2003) Head of
Paleogeophysics Geodynamics at Stockholm
University, Sweden morner_at_pog.nu www.pog.nu
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Some 1200 islands
Welcome to the Maldives
Grouped in some 20 larger atolls
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• The Maldives International Sea Level Project
• March 2000 setting up the project
• Mörner
• November 2000 1 month reseach/expedition
• North Male, Guidhoo, Baa and Raa Atolls
• Mörner, J. F. Laborel, S. Dawson, S. Islam, et
  al.
• February 2001 reef woman investigation
• Mörner, Tooley
• November 2001 1 month research/expedition
• Addu, Foammulah, North Male, Guidhoo, Baa Atolls
• Mörner, J. F. Laborel, Tooley, Collina,
  Allison, et al.
• December 2003 Doomsday called off (TV)
• Mörner, Mortensen, Petersen
• February 2005 post-tsunami research
• Laamu, Guidhoo, Viligili Atolls
• Mörner, S. Dawson, B. Lembke

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The Maldives during LGM and the subsequent
periods Nils-Axel Mörner
The Maldives, is a group of about 1200 small
atoll islands grouped in about 20 larger
atolls. The Holocene reefs seem largely to be a
thin apron upon older reef bodies (gt40,000 BP).
The atolls are surrounded by shore-marks from
the LGM low-stand and several subsequent sea
levels from a punctuated sea level rise. The
old reef structures, exposed for sub-aerial
weathering during lower sea level stands, are
extensively karstified with systems of submarine
caves. This calls for a completely new history
of the islands not only with respect to sea level
changes but primarily with respect to their
environmental conditions during LGM to Younger
Dryas. The post-LGM sea level rise was rapid but
punctuated by a number of steps (submarine
shores). At 4000 BP, the present sea level was
reached. It was followed by a series of rapid sea
level oscillations up to the present (our new sea
level curve). Six paleo-tsunami events are
recorded.
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SeaLevel Changes in the last 130,000 years
THE MALDIVES
No subsidence No flooding Just normal
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At LGM (20 ka), sea level was at about 150 m,
indicating that the geoid trough was even deeper
then. The Maldives now consisted of 20 large
islands, around their edges being surrounded by
reef chimneys of about 150 m height and with a
flat inland depression at around 100 m above sea
level. Climate was warm and wet judging from the
strong karstification. The inland depressions
must have been crossed by river systems and
covered by a dense rainforest. Surely many land
animals and birds lived in the forest but which
ones, we have no records of at present. The
strong karts weathering contributed to the global
carbon budget.
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There is a prominent sea level halt with deltas
and shore cuts at around 65-70 m. This may
represent the Younger Dryas period. The inland
lowlands, now only some 10-20 m above sea level,
were crossed by rivers debouching between the
coastal rim of reef chimneys, now about 60-70 m
high. The environment must have changed
significantly. But rain forests may still
persist.
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After this stage, sea level rose rapidly with
some consistent levels of distinct marks of more
stationary sea level positions. When the inland
basins were flooded, flora and fauna diminished
drastically and only the coastal chimneys
remained above sea level. Time 9000 C14 yrs BP.
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Finally, today, there remain some 1200 islands
primarily formed by coral rubble and coral sand.
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The new sea level curve of the Maldives present
level reached 4000 BP, sea level strongly
oscillating for regional dynamic reasons, a drop
in sea level 1970, no rise in the last 30 years.
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Example of records of short high sea levels. This
coral, today 5-10 cm above mean zero, and in
situ requites a water depth of 60 cm (according
to Laborel), implying a higher sea level of
about 70 cm.
The coral is cut and dated at 2 levels. (2)
1585 35 BP (1) 1635 35 BP
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Sea level oscillations in the last millennium
(cores from two fens) The 2 swamps became lakes
in 1790 and both dried up in 1970
NB. Peat and shell dates differ by 350 years, a
good measure of the local sea correction
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Queens Bath (4) 0.6 m 400 BP (3) 20-30 cm
gt1970 (2) Present HTL (1) Present MTL
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The higher pre-1970 shore is recorded in a map
of 1922.
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At 1970 Sea Level fell some 20 cm Causing
erosion with sand deposition outward,
downward Leaving an old fossil shore and an old
owergrewing surface of grey weathered
corals. The present shore has remained
stable for 30 years
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This is our Maldives story up to today The
Maldives Sea Level Research Project originally
by the INQUA Commission on Sea Level Changes and
Coastal Evolution The most important
conclusions are the -150 m LGM level with
strong karst weathering and likely rain forests
in the inland areas and the total absence of any
on-going sea level rise today implying that the
flooding concept must be called off
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Today I launch a short book entitled The
Greatest Lie Ever Told unfortunately I have to
charge 15 Australian dollars for it