600
I
i
I
l
T
F
/
500 -
Q
-
-;.
>F- -_
Silica precipitates \~. Silica precipitates
/
-
~ 300
Calcite dissolves
~, Calcite precipitate~/~
co
22)
_.J
o
co 200
Amorphous silica ~
/
I00Silica dissolves
~
SHica dissolves
Calcite dissolves
~Calcite precipitates/
0
Quartz
z
5
6
7
8
9
I0
I
pH
Fig. 8.21. Diagram showing the way in which the solubility of calcite and quartz are related to pH. (From Figure 9-7. "Origin of Sedimentary Rocks, Second Edition." Blatt/Middleton/Murray 9 1980. Reprinted by permission of Prentice-Hall, Inc., Upper Saddle River, NJ.)
0
1.013_
Eh
0
-1.0 9 '
pH
Acid
7.0 7.8
t
I
Calcite soluble
~ I-~
Quartz stable
G,oucon,,e
g.o
Alkaline
14
I
I j Calcite stable
! ~ 1"911----Quartz soluble
i i
I I
..~i..
Illite
[~1~~ ~-~"-" PY rites
"~~Siderite
Fig. 8.22. Eh versus pH plot showing the approximate stability fields of important sedimentary minerals.
Compare with Fig. 8.20.
I
i
I
l
T
F
/
500 -
Q
-
-;.
>F- -_
Silica precipitates \~. Silica precipitates
/
-
~ 300
Calcite dissolves
~, Calcite precipitate~/~
co
22)
_.J
o
co 200
Amorphous silica ~
/
I00Silica dissolves
~
SHica dissolves
Calcite dissolves
~Calcite precipitates/
0
Quartz
z
5
6
7
8
9
I0
I
pH
Fig. 8.21. Diagram showing the way in which the solubility of calcite and quartz are related to pH. (From Figure 9-7. "Origin of Sedimentary Rocks, Second Edition." Blatt/Middleton/Murray 9 1980. Reprinted by permission of Prentice-Hall, Inc., Upper Saddle River, NJ.)
0
1.013_
Eh
0
-1.0 9 '
pH
Acid
7.0 7.8
t
I
Calcite soluble
~ I-~
Quartz stable
G,oucon,,e
g.o
Alkaline
14
I
I j Calcite stable
! ~ 1"911----Quartz soluble
i i
I I
..~i..
Illite
[~1~~ ~-~"-" PY rites
"~~Siderite
Fig. 8.22. Eh versus pH plot showing the approximate stability fields of important sedimentary minerals.
Compare with Fig. 8.20.