Abundances of the Elements in the Earth's Crust

ElementApproximate
% by weight
Oxygen
46.6
Silicon
27.7
Aluminum
8.1
Iron
5.0
Calcium
3.6
Sodium
2.8
Potassium
2.6
Magnesium
2.1
All others
1.5

Given the abundance of oxygen and silicon in the crust, it should not be surprising that the most abundant minerals in the earth's crust are the silicates. Although the Earth's material must have had the same composition as the Sun originally, the present composition of the Sun is quite different. The elemental composition of the human body and life in general is quite different.

These general element abundances are reflected in the composition of igneous rocks.

 Index

Tables

Data Reference
Lutgens & Tarbuck
Ch 2
 
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Common Elements Important in Living Organisms

Element
Symbol
Atomic Number
% by Mass in
Solar System
Percent in Earth
Percent in Human Body
Hydrogen
H
1
70.6
0.14
9.5
Helium
He
2
27.5
Trace
Trace
Carbon
C
6
0.30
0.03
18.5
Nitrogen
N
7
0.11
Trace
3.3
Oxygen
O
8
0.59
47
65
Sodium
Na
11
0.0033
2.8
0.2
Magnesium
Mg
12
0.0069
2.1
0.1
Phosphorus
P
15
Trace
0.07
1
Sulfur
S
16
0.0396
0.03
0.3
Chlorine
Cl
17
Trace
0.01
0.2
Potassium
K
19
Trace
2.6
0.4
Calcium
Ca
20
0.006
3.6
1.5
Iron
Fe
26
0.12
5
Trace

The percentages are percent by mass of the indicated elements. Solar system values are from Arnett, see below. The composition of the human body is seen to be distinctly different from the abundance of the elements in the Earth's crust. The elements upon which life is based are often summarized by the combination CHONPS, carbon, hydrogen, oxygen, nitrogen, phosphorous and sulfur. Note that nitrogen is rare on the Earth, but is a major component of proteins, the working molecules of life.

Index

Tables

Data Reference
Audesirk & Audesirk
Ch 2, Table 2-1
 
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Element Abundance in the Solar System

Element
Symbol
Mass Number A
Mass fraction in
parts per million
Atom fraction in
parts per million
Hydrogen-1
H
1
705700
909964
Helium-4
He
4
275200
88714
Oxygen-16
O
16
5920
477
Carbon-12
C
12
3032
326
Nitrogen-14
N
14
1105
102
Neon-20
Ne
20
1548
100
Silicon-28
Si
28
653
30
Magnesium-24
Mg
24
513
28
Iron-56
Fe
56
1169
27
Sulfur-32
S
32
396
16
Helium-3
He
3
35
15
Hydrogen-2
H
2
23
15
Neon-22
Ne
22
208
12
Magnesium-26
Mg
26
79
4
Carbon-13
C
13
37
4
Magnesium-25
Mg
25
69
4
Aluminum-27
Al
27
58
3
Argon-36
Ar
36
77
3
Calcium-40
Ca
40
60
2
Sodium-23
Na
23
33
2
Iron-54
Fe
54
72
2
Silicon-29
Si
29
34
2
Nickel-58
Ni
58
49
1
Silicon-30
Si
30
23
1
Iron-57
Fe
57
28
1

The data above is from Arnett, and the elements are listed in descending order of the atom fraction in the solar system. The percent by mass in the solar system is the mass fraction in parts per million with the decimal point shifted left four places, e.g. hydrogen is 705,700 parts per million in mass and 70.57% by mass. As the lightest atom, it is 91% by number. Since specific isotopes are tabulated here, the percentages would differ slightly if all isotopes of each element are tabulated.

References:

Element abundance wiki

Arnett, David, Supernovae and Nucleosynthesis (First ed.). Princeton, New Jersey: Princeton University Press, 1996.

Index

Tables

 
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