TY - JOUR
T1 - Aeolian activity in northern Amazonia
T2 - Optical dating of Late Pleistocene and Holocene palaeodunes
AU - Teeuw, Richard M.
AU - Rhodes, Edward J.
PY - 2004/1
Y1 - 2004/1
N2 - Palaeodunes were examined on the eastern margin of the Rio Branco-Rupununi savanna, northeast Amazonia. Optical dating suggests that the onset of aeolian activity was between 17 000 and 15 000 yr ago, just after the Last Glacial Maximum. Both the palaeodune axes and modern dominant wind directions have northeast to east-northeast directions, implying no significant shift in atmospheric circulation patterns over northeast Amazonia during the Late Pleistocene to Holocene. Major regional climate change events, such as the Younger Dryas, do not appear to have had any effect on the rates of aeolian deposition at the study site. Aeolian activity appears to have continued to the present day, showing a remarkably constant deposition rate of around 0.13 m kyr-1 initially, increasing smoothly to the present. Until more palaeodunes in northern Amazonia are dated, it is impossible to determine if this record of gradual aeolian deposition is a reliable regional palaeoclimate indicator, rather than being the result of local bioclimatic and geomorphological effects.
AB - Palaeodunes were examined on the eastern margin of the Rio Branco-Rupununi savanna, northeast Amazonia. Optical dating suggests that the onset of aeolian activity was between 17 000 and 15 000 yr ago, just after the Last Glacial Maximum. Both the palaeodune axes and modern dominant wind directions have northeast to east-northeast directions, implying no significant shift in atmospheric circulation patterns over northeast Amazonia during the Late Pleistocene to Holocene. Major regional climate change events, such as the Younger Dryas, do not appear to have had any effect on the rates of aeolian deposition at the study site. Aeolian activity appears to have continued to the present day, showing a remarkably constant deposition rate of around 0.13 m kyr-1 initially, increasing smoothly to the present. Until more palaeodunes in northern Amazonia are dated, it is impossible to determine if this record of gradual aeolian deposition is a reliable regional palaeoclimate indicator, rather than being the result of local bioclimatic and geomorphological effects.
KW - Aeolian activity
KW - Amazonia
KW - Optical dating
KW - Optically stimulated luminescence (OSL)
KW - Palaeodunes
KW - Pleistocene-Holocene
UR - http://www.scopus.com/inward/record.url?scp=1242310254&partnerID=8YFLogxK
U2 - 10.1002/jqs.815
DO - 10.1002/jqs.815
M3 - Article
SN - 0267-8179
VL - 19
SP - 49
EP - 54
JO - Journal of Quaternary Science
JF - Journal of Quaternary Science
IS - 1
ER -