noaa-ocean-13677
Gulf of Aden DSDP231 12Ma Pollen and d13Cwax Data
Feakins, S.J.; Levin, N.E.; Liddy, H.M.; Sieracki, A.; Eglinton, T.I.; Bonnefille, R.
Gulf of Aden DSDP231 12Ma Pollen and d13Cwax Data
2013-01-18
NCDC-Paleoclimatology
ONLINE Files
Pending
https://www.ncdc.noaa.gov/paleo/study/13677
Investigator
S.J.
Feakins
Investigator
N.E.
Levin
Investigator
H.M.
Liddy
Investigator
A.
Sieracki
Investigator
T.I.
Eglinton
Investigator
R.
Bonnefille
earth science
paleoclimate
paleocean
biomarkers
earth science
paleoclimate
paleocean
carbon isotopes
earth science
paleoclimate
paleocean
population abundance
geoscientificInformation
biogeography
11460000 cal yr BP
60000 cal yr BP
Complete
11.89
11.89
48.25
48.25
-2152
-2152
Ocean
Indian Ocean
Arabian Sea
DSDP 231>LATITUDE 11.89>LONGITUDE 48.25
None
Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site.
English
DOC/NOAA/NESDIS/NCEI
National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
https://www.ncdc.noaa.gov/data-access/paleoclimatology-data
DATA Center Contact
Bruce
Bauer
bruce.a.bauer@noaa.gov
paleo@noaa.gov
303-497-6280
303-497-6513
325 Broadway, E/NE31
Boulder
CO
80305-3328
USA
online
ASCII
Feakins, S.J., N.E. Levin, H.M. Liddy, A. Sieracki,
T.I. Eglinton, and R. Bonnefille. 2013.
Northeast African vegetation change over 12 million years.
Geology, Published online January 17, 2013.
doi: 10.1130/G33845.1
Intense debate surrounds the evolution of grasses using the C4
(Hatch-Slack) photosynthesis pathway and the emergence of African
grasslands, often assumed to be one and the same. Here, we bring
new insights with the combination of plant leaf wax carbon isotopic
composition (d13Cwax) and pollen data from marine sediments of the
Gulf of Aden (northeast Africa), which show that C4 biomass increases
were not necessarily associated with regional grassland expansion.
We find broadly opposing trends toward more enriched d13Cwax values
and decreased grass pollen proportions between 12 and 1.4 Ma.
This apparently contradictory evidence can be reconciled if a greater
proportion of the Late Miocene northeast African landscape were
covered by C3 grasses than previously thought, such that C4 grasses
and shrubs replaced a C3 ecosystem including trees and productive
grasslands. In addition, d13Cwax and pollen both indicate that true
rainforests were unlikely to have been extensive in northeast Africa
at any time in the last 12 m.y., although seasonally dry forests
were a significant component of the regional landscape since the Late
Miocene. Here, we extend regionally integrative marine archives
of terrestrial vegetation back to 12 Ma, and we evaluate them in
the context of an updated compilation of pedogenic carbonate d13C
values from East African Rift strata. We identify two distinct
phases of increasing C4 biomass between 11 and 9 Ma (with a
reversal by 4.3 Ma) and then a re-expansion between 4.3 and 1.4 Ma;
surprisingly, neither was associated with grassland expansion.
STUDY NOTES: Plant leaf wax carbon isotopic composition (d13Cwax) data
and pollen counts from marine sediments collected at Deep
Sea Drilling Program (DSDP) site 231, Gulf of Aden, Africa.
Age model from tephra and nannofossils datums correlated
to dated records elsewhere. Vegetation evidence from pollen
assemblage counts, as well as carbon isotopic composition
of plant leaf waxes. Pollen and leaf wax d13C are used
to reconstruct the history of grasslands and C4 grasslands
in NE Africa during the last 11.46 million years.
GET DATA
https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/feakins2013/feakins2013.xls
GET DATA
https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/feakins2013/feakins2013.txt
USA/NOAA
DIF
Version 9.8.4
2018-12-11
2018-12-11