The Quaternary sediments of Singapore

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The ice age. ▫ when mammoths and sabre- toothed tigers really did roam the world ... Organic mud. Mangrove peat. 7070±130 BP. 6190±70 BP. +0.03m rsl.
The Quaternary sediments of Singapore M. Bird, C.H. Chang, N. Shirlaw, T.S. Tan and T.S.Teh

The ice age 



when mammoths and sabretoothed tigers really did roam the world A mere 20,000 years ago 





Globally temperatures were cooler Ice sheets kilometres thick covered Scandinavia, UK, Canada Sea-level was 140m lower

Post-glacial sea-level rise Equivalent sea-level (m) (= ocean volume)

Most ice gone by 6000 BP

Glacial maximum

Thousands of years BP 

At the end of the ice age, the glaciers melted, the water returned the sea and sea-level rose in a series of slow and rapid rises

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The ice age continent of sundaland - you could walk from Singapore to Indonesia

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Sea level changes since the last interglacial

Bathymetry of the Straits of Singapore



Marina MRT tunnel shaft (MAR-5): an 8,000 year old mangrove peat, now 7m below sea-level, overlain by 5 metres of marine clay

Marine clay -7.0m rsl

7530±80 BP

Mangrove peat

-7.4m rsl Pre-transgression Weathering profile

7650±100 BP

Modern mangrove - Pulau Ubin

Characteristics of MAR-5

Marine clay

Mangrove peat

Pre-transgression Weathering profile

KIM CHUAN DEPOT

Kim Chuan MRT Depot Mangrove peat 6190±70 BP

Organic mud +1.43m rsl

Interbedded sand/clay 7070±130 BP

+0.03m rsl Old alluvium

Marine clay -2.5m rsl

6360±240 BP

Mangrove peat -2.9m rsl

7070±90 BP

Pre-transgression Weathering profile

Singapore Management University, Bras Basah

Preliminary sea-level curve for Singapore

Singapore 6,000 years ago (land in green) Pulau Ubins…

NIE

Takashimaya

downtown

Upper and lower marine clay

24,600ybp

137,000 ybp

Sea level changes since the last interglacial LMC

?

UMC Data Pulau Tekong ? Lacustrine ?

Schematic of Quaternary sediments of Singapore