Geology Reference
In-Depth Information
Major oceans
(a)
Black
10
4
Caspian
Jordan
Baltic
10
3
Colorado
Volga
Yu ko n
Mississippi
10
2
Ganges
Congo
Columbia
Orinoco
10
1
Negro
Tefé
(b)
Sea
water
10
4
Evaporation
crystallisation
10
3
Series
Rock dominance
10
2
Series
10
1
Precipitation
dominance
0.2
0.4
0.6
0.8
1.0
Weight Na
+
Weight (Na
+
+ Ca
2+
)
Figure 7 The chemistry of the Earth's surface waters: (a) typical values of the ratio Na
1
/
(Na
1
þ
Ca
21
) as a function of dissolved solids concentrations from various
major rivers and oceans and (b) the processes leading to the observed ratios
(From Gibbs
20
) copyright
r
1970, American Association for the Advance-
ment of Science
In slow-moving water bodies such as lakes and ocean basins, suspended
solids falling to the bottom produce a well-stratified layer of bottom
sediment. This is stratified in terms of age with the oldest sediment at the
bottom (where when suitably pressurised in can form rock) and the
