
223
6
Chronometry
Radionuclides that are linked to one another by the processes of radioactive decay
h
ave
r
elative
c
oncentrations
t
hat
ca
n
b
e
ca
lculated
b
y
t
he
s
imple
l
aws
o
f
r
adioactive
i
ngrowth
o
r,
i
n
m
ore
c
omplicated
ca
ses,
b
y
t
he
B
ateman
e
quations.
I
f
a
t
ime
e
xists
at
w
hich
a
ll
d
escendant
r
adionuclides
h
ave
b
een
r
emoved
f
rom
a
p
arent
m
aterial,
t
hat
t
ime
ca
n
b
e
d
etermined
t
hrough
r
adiochemical
s
eparations
a
nd
t
he
s
ubsequent
me
a-
surement
of the relative concentrations of mothers and daughters at a later time. The
i
nterval
b
etween
t
he
t
ime
t
hat
t
he
s
ample
w
as
p
uried
a
nd
t
he
t
ime
t
hat
i
t
w
as
s
ubse-
quently
a
nalyzed
i
s
d
ened
a
s
t
he
“
age”
o
f
t