San Diego State University by. Nowell. Fall 1976. Approved by: C M. M. 1.) . )lj. /'" / ... t1ethods and Procedures. 2. REGIOt-:AL GEOLOGY. General. Paleozoic .... might have formed the final alteration. ... excavations and mining dumps have been omitted (see Plate I, .... In the Mesocoic era a major thermal event caused.
GEOLOGY OF THE SULFUR-SULFATE DEPOSITS AT THE APACHE .MINES, BAJA CALIFORNIA, .MEXICO
A Thesis Presented to the Faculty of San Diego State University
In Partial Fulfillment
of the Requirements for the Degr ,:e .Master of Science in
Geology
by Nowell Alan Briedis Fall 1976
GEOLOGY OF THE SULFUR-SULFATE DEPOSITS AT THE APACHE MINES, BAJA
MEXICO
A Thesis Presented to the Faculty of San Diego State University
by Nowell Fall 1976
Approved by:
C 1.) . )lj
M. M
{7Jkr J ( /'"
/
)"
/
/
I
G'E S!l.o sq B75 ACKNOWLEDGMENTS
This project wa s made possible by a grant of $1350.00 from the government of Mexico.
I want to thank Ingeniero
Guillermo P. Salas, general director of the Consejo de Recursos Naturales No Renovables, who approved the study, set up the grant, and supplied the aerial photographs. I am very grateful to Scm Diego State University professors R. G. Gastil for suggesting this project and E. E. Roberts for being my thesis chairman and assisting me throughout the study .
I am also grateful to C. M. Marshall and D. Coffey
for proofreading the various drafts of my report. I want to thank the many people at San Diego State University who helped me in particular phases of my work. S. L. Faulkner, E. E. Roberts, and R. G. Gastil assisted in the field work .
Professors K. K. Bertine and R. L. Threet offe red
suggestions and enthisiasm as did my colleagues D. J. Buck, M. 0.
and
H. Hoyt.
OF CONTENTS
Page
l',CKl\IOWLEDGMENTS
iii
LIST OF TABLES
vii
LIST OF FIGURES LIST OF PLATES
viii ix
Chapter l.
2.
INTRODUCTION
1
Location and Geomorphology
1
Previous Studies
3
Purpose
4
t1ethods and Procedures
5
REGIOt-:AL GEOLOGY
lO
General
10
Paleozoic
ll
Mesozoic Reeks
12
Cenozoic Volcanic Rocks
15
Cenozoic Sedimentary Rocks
15
Structure
18
General stratigraphic col'-lmn
18
Pre-volcanic structure
18
Post-volcanic tilting and faulting
20
Geologic History
24
v
Chapter 3.
Page THE WALL ROCK ALTERATION
27
Surface Expression .
29
.
Regional Distribution
30
Alteration Minerals
31
t1ineral Zones
34
Plutonic rocks
35
Sedimentary rocks
....
l,II)
0
... c:
8
·..-t ·rl
> ·rl
:E
rl rd
... ]%
>) \
6
7
>1%
>1\
>1%
Ul
8
9
1\
1\
10
ll
12
>1.\
>1\
500
1%
5000
5000
1000
5
500
5
,.;
.0:
-
_:L__
1\l
4
')
u
.Q
> ]'!.
> 1'!.
>]'I,
> 1\
>1%
> 1\
> 1\
.004
I
500
I
5
I
10 600
-
20
800
500
1
2
40
10
10 500
1000
>)\
500
>l\
100
l.OO
10
Co
1000
10
Cr
50
10
Cu
10
50
5000
100
100
100
soo
lOOO
1000
100
100
500
10
10
5
5
Fe
1\
5000
>1\
lOOO
> l%
1\
1%
5000
5000
>a
>1%
1000
>] %
>l%
> J.'!.
5
Ng
lOOO
lOOO
500
1000
5000
1000
5000
500
50
>1'!.
>)'I;
so
10
100
to
s
10
20 70
30
7000
I
l%
(J\
00
Table 2 (Continued)
-
---
--
--
... 0 "' .... CIJ
:n
"' >-. ....Je "'.:: .-t
'j
4
5
5
6
7
B
500
100
1000
1000
CIJ
"' 1%
"')%
>1%
tli
10
50
50
10
50
5000
10
5
10
80
20
50
10
10
10
5
10
)0
15
500
250
700
1)50
5
4500
5
t1n
I
3
2
.-t
... ....;
... Sample No .
-d
>
.....
Ql
>1
"' >1 CIJ
>· "' H.
> 1%
> I\
>1%
> ]'!;
>1%
> .1\
>l\
l%
Sr
5 00
'l' i
5000
1000
5000
100
> l\
>1 \
>1'1.
1000
5000
1000
5000
100
50
50
1000
>1%
5
50
5
500
500 h
100
v
Zr
>1%
10
100
£n
>1 '1.
>a
100
5 000
100
50
1%
5000
l%
8000
500
5
100
100
10
2
5
_____ ___li_Q__ -
aAIJ concentrations in ppm unl e ss oth e rwise indi c ated. b c d
Refe rence Nockold s and Allen, 1953. nef e ren ce Tooker, 1963. Re feren ce Levinson, 1 9 7
