Parameter
Proxy
Basic assumption(si Empirical relationship
flux
41c I ,"
Pa/""Th
I) ""Th is very
if 1)
and 2) hold,
(accumulaparticle reactive and
changes in the
lion rate)
its production is
231paJ2300yh ratio reflects
constrained (cf.
41a). changes in relative rain
2) 23I
Pa is less
rate
reactive and will be
accumulated in areas
of high particle flux
42
'HetHe
'He is formed by
if the "cosmic input" of
cosmic ray spal1ation
'He and 'HetHe is
reactions at a constant constant over the time
rate
interval under
consideration and the
terrestrial input of 3He is
a minor component, 3He
is very particle reactive,
then the ratio in the
sediment allows
reconstruction of
sedimentation rate (cf.
41c)
43
Altri
elemental ratios:
I) see 41c
similar to
41c
2) if the influx of Al is
taken constant variations
in [AI] can be converted
to accumulation rate
44
REEs (Rare Earth REEs are very particle Concentration changes
Elements)
reactive.
can be
used to follow
evolution
of productivity
though time or space.
There is some potential
that the variation in the
light to heavy·REE ratio
may
be a function of
particle flux (Ruhlin and
Owen 1986)
- -
Selected reference(s)'
Precision (lab.
reproducib-l
Anderson et a!. (1983);
see
41a (but the
Walter et
a!. (this
error will
be larger
volume)
due to propagation
of errors)
Marcantonio et al.
3He
isotopic comp.:
(1996; 1995);
±5%
Farley (1995);
[He]: ±10%
Farley and Patterson
(Marcantonio et al.
(1995)
1995)
Arrhenius (1952)
<1% for both
Murray et a!. (1993)
elements
Dymond et
aJ. (1997)
Dymondet a!.
(1997)
Murray and Leinen
±5 %
in sediments
(1993)
(ICPOES)
Accuracy3
Pitfalls
?
I) the "'Pa flux depends also on the
rate of circulation
2) particle chemistry affects
reactivity of 231 pa
«Walter et al. in
press»
3) the ratio is not affected by
dissolution
?
I) 3He production is not constant
(Farley and Patterson 1995)
2) sediment focussing (see 58)
?
very low solubility; no dissolution
effects
?
Fe- and Mn-oxyhydroxides are
extremely efficient primary and
diagenetic scavengers of REEs and
can thus mask the primary signal
I
0\
0\
~
~
..,
~
~
Proxy
Basic assumption(si Empirical relationship
flux
41c I ,"
Pa/""Th
I) ""Th is very
if 1)
and 2) hold,
(accumulaparticle reactive and
changes in the
lion rate)
its production is
231paJ2300yh ratio reflects
constrained (cf.
41a). changes in relative rain
2) 23I
Pa is less
rate
reactive and will be
accumulated in areas
of high particle flux
42
'HetHe
'He is formed by
if the "cosmic input" of
cosmic ray spal1ation
'He and 'HetHe is
reactions at a constant constant over the time
rate
interval under
consideration and the
terrestrial input of 3He is
a minor component, 3He
is very particle reactive,
then the ratio in the
sediment allows
reconstruction of
sedimentation rate (cf.
41c)
43
Altri
elemental ratios:
I) see 41c
similar to
41c
2) if the influx of Al is
taken constant variations
in [AI] can be converted
to accumulation rate
44
REEs (Rare Earth REEs are very particle Concentration changes
Elements)
reactive.
can be
used to follow
evolution
of productivity
though time or space.
There is some potential
that the variation in the
light to heavy·REE ratio
may
be a function of
particle flux (Ruhlin and
Owen 1986)
- -
Selected reference(s)'
Precision (lab.
reproducib-l
Anderson et a!. (1983);
see
41a (but the
Walter et
a!. (this
error will
be larger
volume)
due to propagation
of errors)
Marcantonio et al.
3He
isotopic comp.:
(1996; 1995);
±5%
Farley (1995);
[He]: ±10%
Farley and Patterson
(Marcantonio et al.
(1995)
1995)
Arrhenius (1952)
<1% for both
Murray et a!. (1993)
elements
Dymond et
aJ. (1997)
Dymondet a!.
(1997)
Murray and Leinen
±5 %
in sediments
(1993)
(ICPOES)
Accuracy3
Pitfalls
?
I) the "'Pa flux depends also on the
rate of circulation
2) particle chemistry affects
reactivity of 231 pa
«Walter et al. in
press»
3) the ratio is not affected by
dissolution
?
I) 3He production is not constant
(Farley and Patterson 1995)
2) sediment focussing (see 58)
?
very low solubility; no dissolution
effects
?
Fe- and Mn-oxyhydroxides are
extremely efficient primary and
diagenetic scavengers of REEs and
can thus mask the primary signal
I
0\
0\
~
~
..,
~
~