Geoscience Reference
In-Depth Information
Table 17.2
Other proxies for desert dust in marine sediments used in literature
Proxy
Proxy for
Location
Citation
Phytoliths
Aridity
Eq. Atlantic
Pokras and Mix ( 1985 )
Freshwater diatoms
Aridity
Eq. Atlantic
(Pokras and Mix 1985 )
Pollen
Aridity
SE Atlantic
Coetzee ( 1976 )
Lipids from plant
waxes
Aridity
Eq. Atlantic
Simoneit ( 1977 )
Ti/Al (Ti in dust, Al
in river mud)
Total dust
Indian Ocean
Weedon and Shimmield ( 1991 )
Zr/Rb (Zr in dust,
Rb in river mud)
Total dust
Eq. Atlantic
Matthewson et al. ( 1995 )
Si/Al (Si in dust, Al
in river mud)
Total dust
Eq. Atlantic
Mulitza et al. ( 2010 )
Pb isotopes
Total dust
Eq. Atlantic
Abouchami and Zabel ( 2003 )
He isotopes
Total dust
Eq. Atlantic
Mukhopadhyay and Kreycik ( 2008 )
Sr/Nd isotopes
Provenance
Eq. Atlantic
Meyer et al. ( 2011 ; 2013 )
Palygorskite (trace
mineral)
Provenance
Sahara
Schütz and Sebert ( 1987 )
Magnetic minerals
Aridity
Eq. Atlantic
Bloemendal et al. ( 1988 )
Hesse ( 1994 ) presented a reconstruction of the Australian dust plume in the
western Pacific Ocean throughout the last 350 kyr BP based on the <63 m fraction
of the terrigenous sediment fraction isolated using the methods described in Rea and
Janecek ( 1981 ). However, this method was developed to characterise Asian dust in
the distal parts of the northern Pacific Ocean, whereas the sediment cores off Aus-
tralia were taken relatively close to the continent. Hence, there may well be a con-
siderable river-derived fraction in the sediment archive that Hesse ( 1994 ) studied.
17.4.2
Other Proxies for Wind-blown Dust
Besides the particle-size distributions of the terrigenous sediment fraction, several
other proxies were suggested useful to characterise dust in subaquatic sediment
archives (see Table 17.2 andalsoChap. 2 ) . The first published detailed study of
the composition of Saharan dust was done by Ehrenberg ( 1847 ), who received
material that Charles Darwin had collected on his travels onboard HMS Beagle
from 1831 to 1836. Ehrenberg recognised all kinds of biogenic material in the
dust, which he classified as freshwater diatoms and plant-derived biogenic silica
called phytoliths. These freshwater diatoms and phytoliths were later found in North
Atlantic sediments (e.g. Kolbe 1957 ) and consequently used to reconstruct Saharan
climate (Pokras and Mix 1985 ; Gasse et al. 1989 ; Alexandre et al. 1997 ) and south-
western African climate (Jansen et al. 1992 ).
An alternative wind-blown land-derived organic fraction is pollen, and they
have been used widely to reconstruct palaeo-environmental conditions in dry areas
around the world, both in marine and lacustrine settings, in South America from
 
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