TITLE:
Origin of the Amazonian Rainforest
AUTHORS:
Nils-Axel Mörner
KEYWORDS:
Amazonian Rainforest, Sea Level Changes, Andean Uplift, Messinian Crisis, Late Miocene
JOURNAL NAME:
International Journal of Geosciences,
Vol.7 No.4,
April
19,
2016
ABSTRACT: In the last 30 ma, the
passive continental margin of South America and the Amazonian basin experienced
three periods of major sea level inundation; viz. at around 20 ma, at around 10
ma and at around 3 ma. The establishment of the immense Amazonian rainforest
ecosystem covering some 6 million square km can neither have occurred during
the periods of high sea level nor at the intermediate periods of arid or
semi-arid climatic conditions. Therefore, the origin of the Amazonian
rainforest of present-day dimensions must be set at the Late Miocene. The
establishment of the Amazonian rainforest implied the withdrawal of enormous
quantities of water from the global hydrological cycle. The drastic increase in
evaporation leading to the Messinian salinity crisis in the Mediterranean
occurred at the same time as the Amazonian rainforest (sensu hodierno)
establishment suggesting a causal linkage.