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Geothermal potential of Egypt
Tecronoph,sics.
17
96 (1983) 77-94
Elsevier Science Publishers
GEOTHERMAL
CHANDLER
B.V.. Amsterdam
POTENTIAL
A. SWANBERG
’ Deparmwnts
in The Netherlands
OF EGYPT
‘, PAUL
OJ Earrh Sciences
- Printed
MORGAN
and Physics,
2 and F.K. BOULOS
New Memco
Stare
’
lJniversrt_v, Las Cruces, N.M.
88003
(U.S.A.) .’ Lunar and Planera? ’ Egrp!ian
Instirure, 3303 NASA
Geological Surq
(Received
August
Road One, Housron, Tex. 77058 (U.S.A.)
and Mmrng Aurhority,
24. 1982, revised version
3 Salah Salem Street, Cairo (Egvpt)
accepted
December
2, 1982)
ABSTRACT
Swanberg.
C.A.. Morgan,
P. and Boulos.
F.K.,
1983. Geothermal
potential
of Egypt.
Tectonoph_wcs.
96:
77-94. One hundred chemically thermal
include
inventory. Hammam
Faraoun
this region
“hot
is the most
gradient None
springs.”
presence
along
Application
potential
although
establish
development.
The
in northern geothermal
Farafra
Such wells constitute
Egypt can be considered resource
in the present
background
chemistry.
Musa (48’C)
Eastern
well (Umm Kharga:
Dakhla,
and NaKCaMg
and to be
and ‘Ain
Desert
of Egypt.
heat flow ( - 72.0 < mW mm’) 358°C)
and Bahariya).
but many of the wells tap deep artesian range.
considered
along both shores of the Gulf of Suez
only one thermal
Desert (Kharga,
of the silica, NaKCa.
of a high temperature
are located
for geothermal
in the 35-43’C
of our samples
The samples
1 spring not included
and
to the Red Sea has above normal
is low ( < 20°C/km),
of water
(T > 30°C)
potential.
with data from the literature.
warm springs
promising
area adjacent
geothermal
the east shore of the Gulf of Suez: Uyun
Additional
some geothermal
volumes
resource.
4 springs
together
In the major oases of the Western
temperature large
are located
the coastal
and therefore
samples.
(70°C).
from nearly all parts of Egypt have been collected
to assess the country’s
20 wells (T z 35’C).
springs
particularly located.
in order
The remaining
The hottest and
and sixty samples of groundwater
analyzed
could be
the regional
aquifers
and produce
a low temperature
geothermal
thermal
including
geothermometers
several
reported
does not indicate
the
at any area we visited.
INTRODUCTION
The present study is part of a much larger cooperative effort among scientists from the Geological Survey of Egypt and several American universities to evaluate the geophysical regime in Egypt, particularly the transition area between the active spreading center of the Red Sea and the stable African platform. These studies have included heat flow, microseismics, gravity, fission tracks, geothermal energy evaluation, and the chemistry of groundwaters. In the present paper, we present the results of our geothermal energy studies.
7x
To date we have sampled which when combined reasonable
coverage
groundwater,
and
and chemically
with another
50 samples
for the entire country. in fact our data
available
groundwaters
sufficient
number
in Egypt.
analyzed taken
of wells and springs
from the literature.
a rather
along
the
available
only three areas not covered by the present
of groundwater,
In most cases we sampled
set includes Only
160 samples
large percentage
Mediterranean
to permit
provide
every available coast
selective
study are the interior
of all were
sampling.
a
The
of Sinai (due to the
political situation), the Nile Delta (the abundance of surface water precludes the need for wells), and the Great Sand Sea area of southwest Egypt (due to extreme inaccessability
and absence
of wells for sampling).
Water chemistry studies of thermal waters are a rapid and inexpensive method of geothermal appraisal. Such studies will provide information regarding the type of geothermal reservoir (liquid or vapor dominated), its possible reservoir base temperature, and any environmental problems that might result from the introduction of geothermal fluids into the local environment. Such studies will also expand the general body of hydrologic knowledge of a given area by providing an indication of the water’s origin, subsurface flow patterns, and chemical quality. The study of non-thermal waters is also an important factor in geochemical exploration for geothermal resources. Such studies establish background chemistry, for comparison with thermal water chemistry and this is required for application of thermal
water mixing
the presence
models.
of factors
Background
that render
geochemical
studies
the use of chemical
also tend to reveal
geothermometers
invalid.
Finally, it is also possible to utilize groundwater chemical data to detect the presence of geothermal resources that are not represented by surface features such as hot springs or hot wells (Swanberg and Alexander, 1979). Several qualitative indicators of subsurface temperature Mariner
and Willey,
demonstrated and
Rowe,
to have widespread 1966) is based
water and the NaKCa the temperature magnesium
1976), but only two quantitative
The silica geothermometer
on the temperature
geothermometer
dependence
correction
application.
to the NaKCa
dependence
(Foumier
of the ratios
have been proposed
geothermometers of quartz
and Truesdell.
of sodium,
geothermometer
potassium has recently
(see
ha1.e been (Foumier solubilit>-
in
1973) is based on and
calcium.
A
been published
by Fournier and Potter (1979). Both geothermometers attempt to determine the last temperature of water-rock equilibrium within the geothermal resemoir and both are subject to possible errors resulting from continued water-rock interactions as the water migrates from the geothermal reservoir to the sampling point, mixing of waters that have equilibrated at different temperatures. and precipitation of the ions involved. Both geothermometers also require that the water chemistry be controlled by temperature dependent reactions. The basic assumptions of chemical geothermometry (1979).
and the equations
are given by Truesdell
(1975) and Foumier
and Potter
79
PROCEDURE
Field work has consisted of traveling temperature and depth, and collecting samples collected
were collected
to each site (well, spring. etc.) recording the a water sample for chemical analysis. Two
at each site. For the 1976 data (numbers
one untreated
sample
and one sample
lP 111, Table I) we
which was diluted
by a 10: 1 ratio
with deionized water. Each sample was placed in a 125-ml polyethelene shipment to the chemical laboratory. For the 1979 data (sample numbers
bottle for with letter
prefixes, Table I) we collected a filtered but otherwise untreated sample along with a sample which has been filtered and treated with 2 ml of 1 : 1 HNO,. The purpose of both the dilution
and the acid treatment
is to stabilize
constituents
such as SiO, and
25”s
Fig. 1. Location
of sample
points.
data taken from the literature
The solid dots represent
as follows:
this inventory.
and the Gulf of Suez data
from lssar et al. (1971). Well depth
brackets.
taken near shore.
Red Sea samples
The solid triangles
represent
“1” prefix from Ezzat (1974), “R” prefix from El Ramly (1969). (m) for literature
samples
are shown
in
1
S = Spring
Sample
1
table),
_
_
II
Wumm
S
60
‘Ain Anbagi
0
26.7
DW DW
58
59
Bir Aweina
26.7
DW
57
Bir ‘Asal
Bir Zareib
30.0
El
Bir Umm Gheig (Dup.
26.7
DW
29.4
26.7
25.0
DW
55
56
26.0
27.7
34.0
22.0
26.0
25.9
Bir Umm Gheig
no. 56)
_
DW
IO
Bir ‘Asali
Bir Nabi
Laseifa
0
S
El6
_
Bir Beizah (Dup. no. 9)
DW
El4
9
Bir El Ranga (Dup. no. 8)
DW
29.2
DW
Bir Beizah
8
Bir El Ranga
Bir Abu Ghalaga
27.0 25.0
DW _
_
DW
Bir El Shadli
6
_
DW
4
G. Sukkari
Bir Hafafit
35.8 28.0
27.0
PW _
DW
27.8
3
_
("C)
T
estimated
2
D
TMg = temperature
Umm Khariga
DW
ss
equations.)
geothermometer;
Well (sample
from
75
57
63
56
79
83
85
92
94
71
84
80
19
77
92
105
73
85
44
46
74
("(3
Ts,o*
by the Na-K-Ca-Mg
exit pipe,
T NaKCa
geothermometer.
112 59 77
96 x3
X8 152
67 45
80
71
69 76
69
88 69
88 69
53 46
RX
88
88 75
78
33
30
cold
40
37
cold
cold
cold
("C)
TMg*
(See Truesdell,
78
33
30
148
40
37
157
150
142
r-7
from iron exit
well operating
by the SiO, geothermome-
Well (sample
iron
estimated
in mine), AW = Artesian
TsIoI = temperature
water
PW = Pumped
M = Mine (standing
top of water
Barramiya
(Dup. no. I)
El7
no.
Barramiya
Deserr
by the Na-K-Ca
1979, for geothermometry
estimated
and Potter,
Barramiya
Eastern
Source
1975 and Fournier
ter; TNaKCa = temperature
from
of discharge),
D = Depth (m); T= in situ temperature;
from point
from shore);
(sample
baled
and wells of Egypt
DW = Dug Well (sample
data for springs
pipe), SL = Salt Lake or salt slough (sample
unless noted),
Source,
depth and geothermal
SS = Sample
continuously
Notes:
Temperature,
TABLE
DW
62
63
64
E2
65
66
67
68
Bir El Sid
Bir Umm Fawakhn
Bir Seiyala
Bir Seiyala (Dup. no. 64)
El ‘Ain
Bir Gahliya
Bir Quei’
Umm Huweitat
DW
El1
Bir Kanayis
Marsa
El3
Bir Wafi
AW AW AW AW
17
18
19
20
5
5 *’New”
Bulaq 5
Garmashin
Garmashin
16
Balad
Ginah
Bulaq Balad
PW
15
PW PW
14
Balad
Kharga
13
Ginah
PW
12
Mahariq
PW
DW
DW
DW
DW
DW
DW
Mahariq
Kharga Oam
El2
Bir Ghadir
Tundaba
E9
El0
Bir Abbad
E7
E8
Bir Faruqiya
E6
Bir Ambar
Bir ‘Aras
DW
E5
Bir El Laqeita
AW
E4
El Laqeita
DW
S
72
of St. Anthony
Monastery
E3
S
71
of St. Paul
Bir El Hammamat
M
69
Umm Huweitat
Monastery
DW
DW
DW
S
DW
DW
DW
61
Bir Beida
_
500
450
105
768
504
262
642
650
160
28
51
2
18
4
450
34.0
33.3
28.8
35.0
33.2
31.0
38.0
37.5
29.0
28.0
26.0
24.5
32.0
34.0
26.0
24.0
30.0
35.0
25.0
0
65
_
29.4
_
25.6
25.0
26.1
25.0
25.0
26.7
0
150
_
0
15
27.X 26.1
48
47
47
48
50
47
52
50
45
74
77
60
46
89
76
78
85
84
57
x1
58
62
63
66
50
96
107
89
91
x5
79
70
257
23x
242
268
300
320
245
237
196
58
88
139
91
159
51
16
191
152
89
86
56
57
IX7
70
136
92
77
84
x2
79
x4
x2
x2
64
61
49
48
75
57
59
68
33
58
66
23
34
cold
51
76
44
19
65
86
56
57
19
59
27
cold
77
x4
x2
79
66
AW S
83
84
‘Ain El Base1
‘Ain El Gedid
S AW AW AW
87
88
89
90
91
92
Bir Sigam
‘Ain El Bishmu
‘Ain Et Bishmu
Halfa Well
American Well
El Maesra “New”
106
Bir El Gidiba Qibii no. 2A
AW
AW
x00
AW
104
LOS
642
AW
103
400
500
AW
AW
640
305
246
755
820
200
250
330
250
650
0 _
_
0
250
102
101
AW
Bir Balat no. IOA
I
?
100
Bir Ma’xara no. 3
Bir Balat no. IO
Bir Tincida no.
Bir Budkhula no.
Bir Ezab El Qasr no. 1A
AW
AW
Bir El Qasr El Balad
99
AW
97
98
Bir El Mahub no. 4
I
AW
96
Bir Ezah El Qasr no. 3
Bir Ezal El Qasr no.
AW
94
95
Bir El Omda AW
AW
Bir El Dinariya
Dokhlu Omis
S AW
S
85
86
‘Ain El Gedid
‘Ain Yausef
s
82
‘Aweina
AW
81
‘Ain El Wadi
Buhariya Oasis
PW
24
EL Qasr
470
31.7
52
54 60
37.2
56
49
49
55
52
58
60
60
60
62
55
53
60
54
53
60
53
53
53
53
53
58
44
45
41.1
38.9
32.X
33.9
37.8
33.9
38.3
42.8
42.x
3x.3
39.0
3x.1
29.4
42.2
31.7
29.4
41.1
28.9
28.3
28.9
26.1
26.7
41.1
29.0
33.5
86
337
6X
73
61
33
62
43
so
59
69
57
57
79
82
87
66
59
x2
91
80
86
60
316
201
202
124
253
PW
45 49
23
32.9 33.9
Baris 14
500 500
252
AW
22
AW
21
NuKC‘.r
Baris 9-A
1
Baris 9-B
I
_~..
I
(W
Sample
no.
Source
TABLE I (continued)
*
50
xx
68
41
61
33
62
43
50
59
69
57
57
cold
cold
cold
cold
cold
cold
cold
52
cold
37
59
60
82
IO
68
66
~__._
T
,d”,a, c
Siwa3
Siwa4
DW DW
Siwal I
Siwa I2
Siwal3
1
Bir El Hilw (N. Siwa)
Bir El Gellaz (N. Siwa)
Abar
DW DW
DW DW
Ah3
Ali
Ah5
Ali
Ah7
Ali
Ah9
AlilO
‘Ain Zeidan
‘Ain Kureshet
‘Ain Abu Shuruf
‘Ain Deriaat
‘Ain Nakb
‘Ain Zeitun
‘Ain Guba
‘Ain Dakruri
Oasis)
Oasis)
‘Ain El Selein (Faiyum
‘Ain El Selein (Faiyum
S S
78
79
DW
DW
DW
PW
PW
Ali
‘Ain Khalit
32.2
0
IO1
69
100
29.0
_
67
22.2
30.0
_
64
65
65
67
65
67
68
68
28
25
29
90
68
67
66
58
68
64
66
65
57
53
54
53
62
s.1
21.7
26.5
_
0
26.0
27.0
26.0
32.0
27.5
27.0
27.0
20.0
21.0
27.0
29.0
29.0
29.0 _
26.0
27.0
22.0
23.0
33.3
35.0
33.9
42.2
_
_
5
5
5 _
7
DW
DW
12
8
600
5
31
9
3
3
2x2
70X
375
_
Ali
Cairo Area
2x0 I220
SL
AW
‘Ain Tamusi
(N. Siwa)
SiwalO
Birket Siwa
El Kandyis
Siwa9
‘Ain Abo El Gabba
AW
Siwa8
AW
Siwa7
‘Ain El Hagali
AW
AW
DW
AW
DW _
‘Ain Meshendit
Siwa6
Government
Well
Siwa5
‘Ain Camisa
Hetat Rahmon
Bir El Dehaba
Guar
Siwal
Siwa2
Well (N. Siwa)
Bir El Noss (N. Siwa)
Government
Siwa Oasis
AW
AW
III
I IO
I
Bir MUI El Balad
Bir Mut
AW
109
AW
AW
Bir Mut 3A
IO7
I OR
El Balad
Bir Mut 3
Bir El Qalamum 96
51 cold
29
26
26
23
cold
cold
cold
cold
24
83
29
70
79
41
cold
30
27
23
56
31
24
24
43
81
64
62
69
77
42
51
166
I61
168
154
156
169
15x
158
93
163
70
79
250
234
158
161
159
205
166
164
I61
220
219
64
77
69
30x
St. Bishoy
St. Bishoy
St. Bishoy
Monastery
Monastery
I
f)W I>W
Med4
Med5
Med6
Med7
MedX
McdY
Med 10
El Qasr 4
Umm El Rakham
Hessien Saad
Angiela
Marsa Garguh
El Aitof
Sidi Barrani
47
26
4
4
I)W IIW
4
4
DW DW
4
DW
4
5
22.5
20.0
19.0
22.0
23.0
20.5
2 I .o
22.0
21 .o
24.0
70.0
6
4X.3
23.0
31.0
30.0
26.0
32.0
29.0
31.0
32.8
32.2
28.9
26.7
_
DW DW
T (“0
0
110
25
55
IO
2
117
95
60
DW
Med3
El Qasr
El Qasr 3
I
S
AW
Med2
Med
PW SL
I El Qasr 2
Mediferruneun
76
CAS30
Faraoun
Uyun Musa
Siwa22
‘Ain Hammam
Sinai
Birket
Makaryus
Siwa2
Bani Salama
Monastery
PW
Siwaf9 PW
DW
Siwalil
AW Ditch
Siwal6
AW
Siwal7
Siwa20
Baramus
Pl,
Siwal4
Siwa 15
Bir Hooker
Monastery
Near St. Bishoy Ceramic
St. Bishoy
Monastery
Wadi Na~run
Monastery DW
0
S
14
S
‘Ain Sukhna (Gulf of Suez)
0
S
13
0
0
S
D
51
ss
50
“0.
Sample
(Gulf of Suez)
‘Ain Sukhna
Sulphur
Spring
New Spring
Helwan
Helwan
Source
TABLE I (continued)
49
4.1
37
52
41
so
s5
50
5X
47
94
75
134
19
71
69
116
71
60
59
69
63
63
82
14
Ll, (“C) --
T?bKC:,
IS3
I60
191
IXX
76
177
200
210
201
cold
cold
X5
cold
52
4%
cold
cold
25
cold
85
232
63
63
33
47
46
24
22
28
28
25
26
26
25
21
38
153
84
x0
x9
141
145
123
136
147
151
129
130
120
X6
(“C)
Medl3
Med14
Medl5
Medl6
El Hawala
Harun
Haleit
Zawyet
Ras El Hekma
Fuka
Med20
Med2l
Med22
70
El5 75
77 93
Burg El Arab
Sidi Krir
Abu Yossef
Red Sea So. of Quseir
Red Sea at Marsa Alam
Birket Qarun
“cold”
indicates
at Marsa
Mediterranean
* The designation
Well no. 3
East Oweinat
Matruah
1T
Well no. 2
East Oweinat
that a magnesium
Siwa14A
2T
El8
River Nile at Luxor
River Nile at Asyut
(Faiyum
Oasis)
Medl9
El Daba 2
Musa Sinai
Medl8
I
El Daba
Uyun
Med17
Gaber
Sanyet
Basin
Medll
Medl2
El Maabdiya
Alam El Rum
correction
cannot
be applied
(see Fournirr
and Potter,
51
1979).
-50
44
_
54
31
55
~ 50
~62
41
64
63
33
82
53
97
95
44
47
42
_
22.8
_
_
20.0
21.0
22.0
22.0
21.0
20.0
20.5
22.0
20.0
19.0
63
sample
_
_
SL _
22.0 20.0
_
0 _
SL
0
I6
17
I2
26
24
ix
IX
I I:
4
I4
47
0 0
_ _
DW
DW
DW
DW
DW
DW
DW
DW
DW
DW
DW
DW lost
288
96
143
60
24
153
186
179
I82
89
167
I61
I78
234
91
265
149
229
92
149
cold
34
cold
60
24
36
70
cold
cold
cold
cold
cold
33
60
cold
33
cold
cold
33
cold
86
Fe. The samples Mexico within within
were sent to the State Soil and Water Testing
State University
for chemical
analyses.
The laboratory
Laboratory,
at New
work was completed
a few days of their shipment from Egypt so that most waters were analyzed three weeks of their collection in the field. The laboratory tests were
conducted
by standard
NaKCa-Mg
analytical
geotemperatures
Table I gives the SiO,,
for each of our samples.
ing those taken from the literature HOT SPRING
methods.
The sample
NaKCa,
locations
and
includ-
are given in Fig. 1.
DISTRIBUTION
Any discussion of hot springs must necessarily take into account the prevailing mean air temperature of the area in question. At Cairo, the mean air temperature is 22°C and temperature of Egypt
depth
may have a mean
data from the western ground
temperature
desert oasis indicate as high as 26°C.
that much
If one accepts
87
Waring’s
(1965) definition
temperature,
then
of a hot spring as one being 8.3”C (15°F)
temperatures
order to be classified
of Egyptian
as thermal.
Using
springs
this definition,
need
above mean air
to exceed
30-35°C
many of the thermal
reported by El Ramly (1969) cannot be strictly their temperatures (25-35°C) may be sufficient
classified as thermal, for some geothermal
Figure
(T > 30°C) that are considered
2 shows the wells (T > 35°C) and springs
be thermal.
Representative
thermal
springs
springs
probably
in Egypt
thermal
water
are located
owe their existence
along
chemistry the shores
to tectonic
is given
even though applications.
in Table
of the Gulf
(or volcanic)
heating
in
springs
to
II. All the
of Suez. These associated
with
the opening of the Red Sea-Gulf of Suez rift. Also shown in Fig. 2 is the Helwan sulphur spring (sample 51). This spring is located just south of Cairo and has been reported as having a temperature of 31.6”C (El Ramly, 1969). This spring exits into a bathing pool where obtaining a reliable temperature measurement is difficult and our measurement deeply circulating
of 28.9”C may be slightly low. This spring probably represents groundwater which has ascended to the surface along a fault zone.
In the Western “ thermal.” plot
of surface
Bahariya
Desert,
there
All of the occurrences temperature
are no springs of thermal
against
that
well depth
for wells
oases. Since all these wells are either artesian
agricultural
purposes,
the surface temperature
can be strictly
classified
as
water are from deep wells. Figure 3 is a from
or pumped
should adequately
the Kharga
and
continuously
for
reflect the bottom-
24 0
I1 200
I 400
Fig. 3. Plot of bottom Bahariya
oases.
I1 I I I I , I I 600 000 1000 1200 1400 DEPTH (ml
hole temperature
against
depth
for the deep artesian
wells from the Kharga
and
TABLE
II
Chemistry
of representative
Sample
Temp.
no. *
(“C)
waters
Ca
Na
Mg
K
Cl
co1
35.8
165.3
98.2
469.4
3.1
1038.4
0
E4
35
187.6
50.2
512.2
14.2
730.7
0
13
37.5
19.4
8.7
loo.5
30.1
20.6
0
14
38.0
25.8
Ii.7
66.0
26.6
5.3
0
17
35.0
35.7
21.3
57.2
35.2
102.1
0
87
41.1
15.6
15.3
45.1
6.6
73.4
0
3
CAS
thermal
90
42.2
13.8
14.3
48.3
7.0
81.5
0
94
39.0
14.2
6.8
22.3
3.5
1.8
0
96
42.8
9.2
7.0
13.6
4.7
0
0
103
38.9
Il.0
7.5
14.5
6.0
3.9
0
108
42.2
11.4
6.4
13.6
18.0
110
35.0
22.6
8. I
28.7
8.6
76
48.3
196.8
66.4
556.6
30
70.0
623.0
150.5
4272.9
74
32.8
479.4
255.0
1643.3
51
28.9
282.0
151.5
1382.4
24 -
0
I,
8
200
400
Fig. 4. Plot of bottom
/
/
I
0
0
9.9
0
8.6
904.1
0
151.3
7176.4
0
45.0
3442.3
0
29.3
2302.1
0
/ / L 3 I I
600
800 1000 DEPTH (ml hole temperature
1200
I400
against
depth
for the deep artesian
wells from the Dakhla
oasis.
89
HCO,
TDS
so4
PH
F
B
Fe
SiO z
208.7
587.9
2692
7.42
1.07
0.48
222.3
557.6
2200
7.34
0.16
0.41
0.19
239.2
73.0
492
7.96
0.18
0.90
< 0.10
14.0
194.0
61.5
280
7.98
0.08
1.14
< 0.10
12.5
109.8
86.5
468
7.46
0.06
0.45
< 0.10
13.0
86.6
25.0
264
7.10
0.05
0.36
0.23
18.5
95.2
21.1
268
6.93
0.05
0.34
0.35
18.5
46.4
61.5
140
6.50
0.03
< 0.20
0.93
19.0
47.6
50.0
108
6.72
0
< 0.20
0.10
18.0
65.9
32.7
141
6.93
0.02
< 0.20
< 0.10
16.5
52.5
46.1
148
6.65
0
-c 0.20
0.16
19.0
52.5
71.1
190
6.4
0.03
< 0.20
0.31
15.5
104.9
614.8
2844
-
0.73
1.05
2.98
27.0
< 0.1
34.0 16.9
135.4
1400.0
13909
6.98
1.84
2.21
0.11
42.5
162.3
922.2
8992
7.04
1.25
2.34
-c 0.10
20.0
272.1
845.3
7048
7.11
1.65
4.02
-c 0.10
32.0
l
Sample
no. refer to Fig. 1.
hole temperature
and can thus be used to estimate
squares fit to these data respectively. The former Morgan
the geothermal
gradient.
yield a slope and intercept of 16.5 mK/m value is consistent with the gradient data
et al. (1980) for northern
Egypt. The latter value is consistent
A least
and 26.O”C reported by with the mean
annual ground temperature of Egypt (26.6’C) calculated on the basis of the temperatures observed at the top of the water table for the hand-dug wells of the Eastern Desert. Thus, it appears that the hot wells of these oases owe their thermal nature
to heating
exploitable
The situation temperature-depth intercept anomalously escarpment
by a normal
geothermal
to low geothermal
gradient
and not to the presence
of
reservoirs.
at the Dakhla
oasis is somewhat
different.
data from wells at the Dakhla
of 11.8 mK/m
and
high temperatures forming the northern
29.4”C,
respectively.
A least squares
fit to the
oasis (Fig. 4) yields a slope and Further,
the wells that
show
are concentrated to the north (Fig. 5), near the boundary of the oasis. These data are most easily
reconciled by assuming that water, heated by a normal to low geothermal gradient, is ascending along conduits at the north end of the oasis and migrating south through the principal aquifers. Finally, it is worth noting that two regions of Egypt have shown thermal activity in the recent past. These are the extinct geysers on both sides of the Cairo-Suez highway and the Jebel Uweinat area of southwest Egypt (El Ramly, 1969).
90
200 -
290
50’
29010’
DAKHLA
-
25’50’
25O50’
OASIS
25O40’
-4
wells with respect
to the
25O40’
.
106
Fig. 5. Sketh map of the Dakhla escarpment
oasis showing
the locations
of the hottest
at the north end of the oasis.
SUBSURFACE
TEMPERATURE
ESTIMATES
The silica, NaKCa, and NaKCaMg geothermometers have been applied to all the samples collected as part of the present survey and the results are given in Table I. A quick scan of these data fails to reveal any samples with abnormally high geotemperatures.
Figure 6 shows the silica geotemperatures
for the thermal
subset
histogram
the silica geotemperatures
waters
included
Faraoun
(sample
beneath
a histogram
in this inventory.
showing
With
CAS 30) the thermal
the possible
exception
waters plotted of ‘Ain
as a
for all Hammam
waters give results that are comparable
to the
non-thermal waters for both the Eastern and Western Desert. Thus this geothermometer cannot be used to infer the presence of abnormally high subsurface temperatures. A similar conclusion is reached by analysis of the NaKCa and NaKCaMg geotemperatures. Figure 7 shows a plot (and least squares regression) of the NaKCa temperatures against SiO, temperatures for the thermal and non-thermal waters of the Eastern Desert. If the groundwater chemistry is being controlled by temperature dependent reactions, this plot should show a positive correlation. The data in Fig. 7 not only fail to show such a correlation but also fail to show elevated
91
WERN
DESERT
j--L
eii
WdTERS
.--I:
n= 88
40
THERMAL ”
meon=55.2 z 11.WC
ITeD”
=
17
=
57.314.i’C
WTERS
34.1 i 30 -
20 z e z z
IO-
g,
p-y
23 I
0
L
80
100
120
60 60 T6,02 V’C)
IO0
120
20
w
2
EJ_STERN
“0
20
Fig. 6. Histogram (bottom)
DESERT
deserts.
40
of silica geotemperatures Note that both the thermal
that the values are more compatible
for all groundwaters and non thermal
with low temperature
from
the western
(top)
and
waters yield similar geotemperatures,
rather
than high temperature
eastern and
hydrothermal
activity EASTERN
DESERT
WELL OR SPRING 1, T”ERMIL WELL 0R SPRlW l
,““I 0
20
40
”
60 T&O2
Fig. 7. Plot of NaKCa Desert.
s ’
80 (W
)
L
100
geotemperatures
Note the lack of any obvious
s
“1
120
I40
against
silica geotemperatures
high temperature
geothermal
for groundwaters
fluids.
of the Eastern
92
01 0
I”“’ 20
I’ I ( I ” 1 60 80 100 120 140 TS,02 VT)
40
Fig. 8. Plot of NaKCaMg Desert.
geotemperatures
Note the lack of any obvious
against
silica geotemperatures
high temperature
geothermal
for groundwaters
of the Eastern
fluids.
geotemperatures for the thermal waters relative to the non-thermal waters. A more realistic plot is obtained by plotting (with a least squares regression) the NaKCaMg temperatures the value
against of applying
the SiO, temperatures the magnesium
(Fig. 8). This improvement
correction,
underscores
at least for this data
set. Still.
however, there is no tendency for the thermal waters to give higher geotemperatures than the non-thermal waters and we thus conclude that there is no evidence from the geothermometry associated
TABLE
data
to support
the existence
with any of the thermal
springs
of a major
geothermal
of Egypt.
III
Heat flow estimates
of Egypt based on the silica heat flow technique
Location
Number samples
of
Ts,o, (“C)
r, (“C)
4 (mW m-‘)
Traditional (mW mm’)
Eastern
Desert
44
75.4*
15.3
21.9
12.2
77.6 rl
Kharga
Oasis
13
47.55
2.4
26.0
32.1
40-45
12
54.8*
2.8
26.0
43.0 46.1
Bahariya
Oasis
18
55.1 k
4.2
24.4
21
55.4*
17.3
21.2
51.0
22 7
60.3 k 13.7
26.4
50.6
74.7 * 19.4
26.0
12.7
Cairo Area
4
24.9
96.0
Sinai (West Coast)
4
89.2 + 13.4 73.8 + 14.6
25
72.8
Dakhla
anomaly
Oasis
Mediterranean
Coast
Siwa Oasis Wadi Natrun
a Morgan
et al. (1980).
’ Morgan
et al. (1976).
80-100
.J
b
q
93
SILICA
HEAT FLOW
Swanberg and Morgan (1979, 1980) have shown that it is possible to use the silica content of groundwaters to estimate regional heat flow. Normally, this technique is used to supplement where
existing
heat flow data by providing
additional
coverage
in areas
traditional data are sparse. The appropriate equation is q = (7”,o, - q;,)/m in “C, T, is the mean Ts,o is the quartz conductive silica geotemperature
where annual ground temperature in “C, m is 670°C m2 W-’ and q is heat flow in mW m -l. Table III gives the silica heat flow data for various parts of Egypt. In general the agreement between the silica and the traditional heat flow data is good (Swanberg and Morgan, 1980). Eastern Desert heat flow averages 72.2 mW mp2 which is higher than is normally observed in stable platform areas and implies a major heat flow anomaly in the Precambrian of eastern Egypt. The heat flow throughout the western desert oases and along the Mediterranean coast is low ( < 51 mW mm’). On the basis of a very scanty data set, it would appear that high heat flow may exist from the Gulf of Suez area as far west as the Cairo-Faiyum-Wadi Natrun area. CONCLUSIONS
The use of silica estimating
regional
times normal) Hammam
geotemperatures
exists on the border
Faraoun,
of groundwater
heat flow in Egypt. A relatively
is a valuable
technique
for
high heat flow zone (1.7 to 2.3
of the Gulf of Suez and this area contains
‘Ain
the hottest spring in Egypt at 70°C. This zone, which is the most
favorable for geothermal exploration and development, could possibly extend as far west as Cairo and the Faiyum oasis and Wadi Natrum areas based on the groundwater
silica data, extinct
The Eastern
Desert
in general
Geysers
and the historic
has a moderately
seismicity
high regional
of these areas. heat flow of about
75 mW rnp2 based on both the silica data and traditional measurements (Morgan et al., 1980). This area should also be favorable for geothermal discovery although only one thermal well was located during the present study. The Western
Desert has low regional
heat flow ( < 50 mW me2)
and correspond-
ingly low geothermal potential. However, many of these oases (perhaps all of them) are underlain by deep artesian aquifers which produce high quality water in the 30-45°C
temperature
range. These aquifers
may have low temperature
potential. A similar deep artesian aquifer has been observed E4, Table I, Fig. 2) in the Eastern Desert between the River hills. Therefore, it is possible that much of the area immediately also have low temperature geothermal potential. There is no that a major high temperature geothermal field underlies any
geothermal
at El Laqeita (sample Nile and the Red Sea east of the Nile may geochemical evidence area we visited.
94
ACKNOWLEDGEMENTS
The present study could not have been completed without the considerable assistance of Dr. Rushdi Said, and Mr. Gala1 A. Moustafa, Consecutive Directors of the Egyptian
Survey and Mining
Mr. A.A. El-Sheriff, Daggett,
Authority.
Mr. A.A. El-Sayed,
and Mr. T. Roemer
We also acknowledge
Mr. S.F. Hennin,
Mr. N.Z. Basta, Mr. Y.S. Melic, Dr. P.H.
for their help with the data collection.
The work was
funded by the U.S. National Science Foundation through grant numbers EAR7723354 and INT78-16649 from the Earth Sciences program and the Office of International
Programs,
respectively.
REFERENCES
El Ramly,
I.M., 1969, Recent
Proc. Int. Geol. Congr.,
review of investigations
Ezzat, M.A.. 1974. Exploitation the Arab Republic Reclamation, Fournier. Fournier,
in El-Wadi
A.,
in the U.A.R.
project
Conditions.
area. Groundwater
Ministry
Series in
of Agriculture
and Land
correction
to the Na K Ca chemical
geothermometer.
of underground
temperatures
from the silica content
of
and wet steam wells. Am. J. Sci., 264: 685-697.
Cosmochim.
Rosenthal,
springs
Acta, 43: 1543% 1550.
R.O. and Truesdell,
mineralization
El-Gedid
Hydrogeologic
R.O. and Rowe, J.J., 1966. Estimation
Geochim. Issar,
1. Regional
R.W., 1979. Magnesium
Cosmochim.
water from hot springs Fournier,
and mineral
121 pp.
R.O. and Potter,
Geochim.
of groundwater
of Egypt,
Cairo,
on the thermal
23rd, 19: 201-213.
A.N.,
1973. An empirical
Na K Ca geothermometer
for natural
waters.
Acta, 37: 1255-1275.
E., Eckstein,
phenomena
Y. and
Bogoch.
along the eastern
R.,
1971.
Formation
waters.
hot
springs.
and
shore of the Gulf of Suez. Bull. Int. Assoc. Sci. Hydrol..
XVI: 25544. Mariner,
R.H. and Willey, L.M.,
California. Morgan,
J. Geophys.
P., Blackwell,
gradient National
on Thermal
Technical
Swanberg,
C.A.
content
and
Morgan,
Mono County,
P.G..
1976. Preliminary
geothermal
and
Volcanism
In: Proc.
of the Mediterranean
Area.
Hennin,
S.F..
El-Sayed.
D.A..
and
Basta.
N.Z..
1980.
Ann. Geol. Surv. Egypt. X: 971-987.
P., 1979. The linear
file WATSTORE
Geology,
relation
7: 10%
between
in geothermal
explora-
I1 I.
temperatures
based
heat flow: a new heat flow map of the United
on the sihca
States. Pure Appl.
117: 227-241. J. Geophys.
A.H.,
P., 1980. The silica heat flow interpretation of Section
III: Geochemical
and Use of Geothermal
Office, Washington,
1965. Thermal
technique:
assumptions
and
Res., 85: 7206-7214.
1975. Summary
Printing G.A..
in Long Valley.
Vol. 1: 424-438.
Valley, California.
and regional
Symp. on the Development Govt.
Energy
Athens,
F.K.
Africa,
F.K. and Salib.
S.. 1979. Use of water quality
C.A. and Morgan,
applications.
Waring,
Boulos,
from the Imperial
of groundwater
Geophys.,
‘Truesdell.
C.A.,
C.A. and Alexander,
Swanberg,
waters
Egypt and the Gulf of Suez from oil well data.
Geothermal
of Athens,
studies in northeast
tion: an example
of thermal
J.C., Boulos.
Waters,
University
P.. Swanberg,
Geothermal
Swanberg,
D.P., Farris,
and heat flow values for northern
Int. Congr. Morgan,
1976. Geochemistry
Res., 81: 792-800.
springs
techniques
Resources,
in exploration.
San Francisco,
Proc. 2nd U.N.
Calif.. May 1975. U.S.
pp. LIII-LXXIX. of the United
U.S. Geol. Surv., Prof. Pap., 492: 383 pp.
States and other countries
of the world-a
summary.
17
96 (1983) 77-94
Elsevier Science Publishers
GEOTHERMAL
CHANDLER
B.V.. Amsterdam
POTENTIAL
A. SWANBERG
’ Deparmwnts
in The Netherlands
OF EGYPT
‘, PAUL
OJ Earrh Sciences
- Printed
MORGAN
and Physics,
2 and F.K. BOULOS
New Memco
Stare
’
lJniversrt_v, Las Cruces, N.M.
88003
(U.S.A.) .’ Lunar and Planera? ’ Egrp!ian
Instirure, 3303 NASA
Geological Surq
(Received
August
Road One, Housron, Tex. 77058 (U.S.A.)
and Mmrng Aurhority,
24. 1982, revised version
3 Salah Salem Street, Cairo (Egvpt)
accepted
December
2, 1982)
ABSTRACT
Swanberg.
C.A.. Morgan,
P. and Boulos.
F.K.,
1983. Geothermal
potential
of Egypt.
Tectonoph_wcs.
96:
77-94. One hundred chemically thermal
include
inventory. Hammam
Faraoun
this region
“hot
is the most
gradient None
springs.”
presence
along
Application
potential
although
establish
development.
The
in northern geothermal
Farafra
Such wells constitute
Egypt can be considered resource
in the present
background
chemistry.
Musa (48’C)
Eastern
well (Umm Kharga:
Dakhla,
and NaKCaMg
and to be
and ‘Ain
Desert
of Egypt.
heat flow ( - 72.0 < mW mm’) 358°C)
and Bahariya).
but many of the wells tap deep artesian range.
considered
along both shores of the Gulf of Suez
only one thermal
Desert (Kharga,
of the silica, NaKCa.
of a high temperature
are located
for geothermal
in the 35-43’C
of our samples
The samples
1 spring not included
and
to the Red Sea has above normal
is low ( < 20°C/km),
of water
(T > 30°C)
potential.
with data from the literature.
warm springs
promising
area adjacent
geothermal
the east shore of the Gulf of Suez: Uyun
Additional
some geothermal
volumes
resource.
4 springs
together
In the major oases of the Western
temperature large
are located
the coastal
and therefore
samples.
(70°C).
from nearly all parts of Egypt have been collected
to assess the country’s
20 wells (T z 35’C).
springs
particularly located.
in order
The remaining
The hottest and
and sixty samples of groundwater
analyzed
could be
the regional
aquifers
and produce
a low temperature
geothermal
thermal
including
geothermometers
several
reported
does not indicate
the
at any area we visited.
INTRODUCTION
The present study is part of a much larger cooperative effort among scientists from the Geological Survey of Egypt and several American universities to evaluate the geophysical regime in Egypt, particularly the transition area between the active spreading center of the Red Sea and the stable African platform. These studies have included heat flow, microseismics, gravity, fission tracks, geothermal energy evaluation, and the chemistry of groundwaters. In the present paper, we present the results of our geothermal energy studies.
7x
To date we have sampled which when combined reasonable
coverage
groundwater,
and
and chemically
with another
50 samples
for the entire country. in fact our data
available
groundwaters
sufficient
number
in Egypt.
analyzed taken
of wells and springs
from the literature.
a rather
along
the
available
only three areas not covered by the present
of groundwater,
In most cases we sampled
set includes Only
160 samples
large percentage
Mediterranean
to permit
provide
every available coast
selective
study are the interior
of all were
sampling.
a
The
of Sinai (due to the
political situation), the Nile Delta (the abundance of surface water precludes the need for wells), and the Great Sand Sea area of southwest Egypt (due to extreme inaccessability
and absence
of wells for sampling).
Water chemistry studies of thermal waters are a rapid and inexpensive method of geothermal appraisal. Such studies will provide information regarding the type of geothermal reservoir (liquid or vapor dominated), its possible reservoir base temperature, and any environmental problems that might result from the introduction of geothermal fluids into the local environment. Such studies will also expand the general body of hydrologic knowledge of a given area by providing an indication of the water’s origin, subsurface flow patterns, and chemical quality. The study of non-thermal waters is also an important factor in geochemical exploration for geothermal resources. Such studies establish background chemistry, for comparison with thermal water chemistry and this is required for application of thermal
water mixing
the presence
models.
of factors
Background
that render
geochemical
studies
the use of chemical
also tend to reveal
geothermometers
invalid.
Finally, it is also possible to utilize groundwater chemical data to detect the presence of geothermal resources that are not represented by surface features such as hot springs or hot wells (Swanberg and Alexander, 1979). Several qualitative indicators of subsurface temperature Mariner
and Willey,
demonstrated and
Rowe,
to have widespread 1966) is based
water and the NaKCa the temperature magnesium
1976), but only two quantitative
The silica geothermometer
on the temperature
geothermometer
dependence
correction
application.
to the NaKCa
dependence
(Foumier
of the ratios
have been proposed
geothermometers of quartz
and Truesdell.
of sodium,
geothermometer
potassium has recently
(see
ha1.e been (Foumier solubilit>-
in
1973) is based on and
calcium.
A
been published
by Fournier and Potter (1979). Both geothermometers attempt to determine the last temperature of water-rock equilibrium within the geothermal resemoir and both are subject to possible errors resulting from continued water-rock interactions as the water migrates from the geothermal reservoir to the sampling point, mixing of waters that have equilibrated at different temperatures. and precipitation of the ions involved. Both geothermometers also require that the water chemistry be controlled by temperature dependent reactions. The basic assumptions of chemical geothermometry (1979).
and the equations
are given by Truesdell
(1975) and Foumier
and Potter
79
PROCEDURE
Field work has consisted of traveling temperature and depth, and collecting samples collected
were collected
to each site (well, spring. etc.) recording the a water sample for chemical analysis. Two
at each site. For the 1976 data (numbers
one untreated
sample
and one sample
lP 111, Table I) we
which was diluted
by a 10: 1 ratio
with deionized water. Each sample was placed in a 125-ml polyethelene shipment to the chemical laboratory. For the 1979 data (sample numbers
bottle for with letter
prefixes, Table I) we collected a filtered but otherwise untreated sample along with a sample which has been filtered and treated with 2 ml of 1 : 1 HNO,. The purpose of both the dilution
and the acid treatment
is to stabilize
constituents
such as SiO, and
25”s
Fig. 1. Location
of sample
points.
data taken from the literature
The solid dots represent
as follows:
this inventory.
and the Gulf of Suez data
from lssar et al. (1971). Well depth
brackets.
taken near shore.
Red Sea samples
The solid triangles
represent
“1” prefix from Ezzat (1974), “R” prefix from El Ramly (1969). (m) for literature
samples
are shown
in
1
S = Spring
Sample
1
table),
_
_
II
Wumm
S
60
‘Ain Anbagi
0
26.7
DW DW
58
59
Bir Aweina
26.7
DW
57
Bir ‘Asal
Bir Zareib
30.0
El
Bir Umm Gheig (Dup.
26.7
DW
29.4
26.7
25.0
DW
55
56
26.0
27.7
34.0
22.0
26.0
25.9
Bir Umm Gheig
no. 56)
_
DW
IO
Bir ‘Asali
Bir Nabi
Laseifa
0
S
El6
_
Bir Beizah (Dup. no. 9)
DW
El4
9
Bir El Ranga (Dup. no. 8)
DW
29.2
DW
Bir Beizah
8
Bir El Ranga
Bir Abu Ghalaga
27.0 25.0
DW _
_
DW
Bir El Shadli
6
_
DW
4
G. Sukkari
Bir Hafafit
35.8 28.0
27.0
PW _
DW
27.8
3
_
("C)
T
estimated
2
D
TMg = temperature
Umm Khariga
DW
ss
equations.)
geothermometer;
Well (sample
from
75
57
63
56
79
83
85
92
94
71
84
80
19
77
92
105
73
85
44
46
74
("(3
Ts,o*
by the Na-K-Ca-Mg
exit pipe,
T NaKCa
geothermometer.
112 59 77
96 x3
X8 152
67 45
80
71
69 76
69
88 69
88 69
53 46
RX
88
88 75
78
33
30
cold
40
37
cold
cold
cold
("C)
TMg*
(See Truesdell,
78
33
30
148
40
37
157
150
142
r-7
from iron exit
well operating
by the SiO, geothermome-
Well (sample
iron
estimated
in mine), AW = Artesian
TsIoI = temperature
water
PW = Pumped
M = Mine (standing
top of water
Barramiya
(Dup. no. I)
El7
no.
Barramiya
Deserr
by the Na-K-Ca
1979, for geothermometry
estimated
and Potter,
Barramiya
Eastern
Source
1975 and Fournier
ter; TNaKCa = temperature
from
of discharge),
D = Depth (m); T= in situ temperature;
from point
from shore);
(sample
baled
and wells of Egypt
DW = Dug Well (sample
data for springs
pipe), SL = Salt Lake or salt slough (sample
unless noted),
Source,
depth and geothermal
SS = Sample
continuously
Notes:
Temperature,
TABLE
DW
62
63
64
E2
65
66
67
68
Bir El Sid
Bir Umm Fawakhn
Bir Seiyala
Bir Seiyala (Dup. no. 64)
El ‘Ain
Bir Gahliya
Bir Quei’
Umm Huweitat
DW
El1
Bir Kanayis
Marsa
El3
Bir Wafi
AW AW AW AW
17
18
19
20
5
5 *’New”
Bulaq 5
Garmashin
Garmashin
16
Balad
Ginah
Bulaq Balad
PW
15
PW PW
14
Balad
Kharga
13
Ginah
PW
12
Mahariq
PW
DW
DW
DW
DW
DW
DW
Mahariq
Kharga Oam
El2
Bir Ghadir
Tundaba
E9
El0
Bir Abbad
E7
E8
Bir Faruqiya
E6
Bir Ambar
Bir ‘Aras
DW
E5
Bir El Laqeita
AW
E4
El Laqeita
DW
S
72
of St. Anthony
Monastery
E3
S
71
of St. Paul
Bir El Hammamat
M
69
Umm Huweitat
Monastery
DW
DW
DW
S
DW
DW
DW
61
Bir Beida
_
500
450
105
768
504
262
642
650
160
28
51
2
18
4
450
34.0
33.3
28.8
35.0
33.2
31.0
38.0
37.5
29.0
28.0
26.0
24.5
32.0
34.0
26.0
24.0
30.0
35.0
25.0
0
65
_
29.4
_
25.6
25.0
26.1
25.0
25.0
26.7
0
150
_
0
15
27.X 26.1
48
47
47
48
50
47
52
50
45
74
77
60
46
89
76
78
85
84
57
x1
58
62
63
66
50
96
107
89
91
x5
79
70
257
23x
242
268
300
320
245
237
196
58
88
139
91
159
51
16
191
152
89
86
56
57
IX7
70
136
92
77
84
x2
79
x4
x2
x2
64
61
49
48
75
57
59
68
33
58
66
23
34
cold
51
76
44
19
65
86
56
57
19
59
27
cold
77
x4
x2
79
66
AW S
83
84
‘Ain El Base1
‘Ain El Gedid
S AW AW AW
87
88
89
90
91
92
Bir Sigam
‘Ain El Bishmu
‘Ain Et Bishmu
Halfa Well
American Well
El Maesra “New”
106
Bir El Gidiba Qibii no. 2A
AW
AW
x00
AW
104
LOS
642
AW
103
400
500
AW
AW
640
305
246
755
820
200
250
330
250
650
0 _
_
0
250
102
101
AW
Bir Balat no. IOA
I
?
100
Bir Ma’xara no. 3
Bir Balat no. IO
Bir Tincida no.
Bir Budkhula no.
Bir Ezab El Qasr no. 1A
AW
AW
Bir El Qasr El Balad
99
AW
97
98
Bir El Mahub no. 4
I
AW
96
Bir Ezah El Qasr no. 3
Bir Ezal El Qasr no.
AW
94
95
Bir El Omda AW
AW
Bir El Dinariya
Dokhlu Omis
S AW
S
85
86
‘Ain El Gedid
‘Ain Yausef
s
82
‘Aweina
AW
81
‘Ain El Wadi
Buhariya Oasis
PW
24
EL Qasr
470
31.7
52
54 60
37.2
56
49
49
55
52
58
60
60
60
62
55
53
60
54
53
60
53
53
53
53
53
58
44
45
41.1
38.9
32.X
33.9
37.8
33.9
38.3
42.8
42.x
3x.3
39.0
3x.1
29.4
42.2
31.7
29.4
41.1
28.9
28.3
28.9
26.1
26.7
41.1
29.0
33.5
86
337
6X
73
61
33
62
43
so
59
69
57
57
79
82
87
66
59
x2
91
80
86
60
316
201
202
124
253
PW
45 49
23
32.9 33.9
Baris 14
500 500
252
AW
22
AW
21
NuKC‘.r
Baris 9-A
1
Baris 9-B
I
_~..
I
(W
Sample
no.
Source
TABLE I (continued)
*
50
xx
68
41
61
33
62
43
50
59
69
57
57
cold
cold
cold
cold
cold
cold
cold
52
cold
37
59
60
82
IO
68
66
~__._
T
,d”,a, c
Siwa3
Siwa4
DW DW
Siwal I
Siwa I2
Siwal3
1
Bir El Hilw (N. Siwa)
Bir El Gellaz (N. Siwa)
Abar
DW DW
DW DW
Ah3
Ali
Ah5
Ali
Ah7
Ali
Ah9
AlilO
‘Ain Zeidan
‘Ain Kureshet
‘Ain Abu Shuruf
‘Ain Deriaat
‘Ain Nakb
‘Ain Zeitun
‘Ain Guba
‘Ain Dakruri
Oasis)
Oasis)
‘Ain El Selein (Faiyum
‘Ain El Selein (Faiyum
S S
78
79
DW
DW
DW
PW
PW
Ali
‘Ain Khalit
32.2
0
IO1
69
100
29.0
_
67
22.2
30.0
_
64
65
65
67
65
67
68
68
28
25
29
90
68
67
66
58
68
64
66
65
57
53
54
53
62
s.1
21.7
26.5
_
0
26.0
27.0
26.0
32.0
27.5
27.0
27.0
20.0
21.0
27.0
29.0
29.0
29.0 _
26.0
27.0
22.0
23.0
33.3
35.0
33.9
42.2
_
_
5
5
5 _
7
DW
DW
12
8
600
5
31
9
3
3
2x2
70X
375
_
Ali
Cairo Area
2x0 I220
SL
AW
‘Ain Tamusi
(N. Siwa)
SiwalO
Birket Siwa
El Kandyis
Siwa9
‘Ain Abo El Gabba
AW
Siwa8
AW
Siwa7
‘Ain El Hagali
AW
AW
DW
AW
DW _
‘Ain Meshendit
Siwa6
Government
Well
Siwa5
‘Ain Camisa
Hetat Rahmon
Bir El Dehaba
Guar
Siwal
Siwa2
Well (N. Siwa)
Bir El Noss (N. Siwa)
Government
Siwa Oasis
AW
AW
III
I IO
I
Bir MUI El Balad
Bir Mut
AW
109
AW
AW
Bir Mut 3A
IO7
I OR
El Balad
Bir Mut 3
Bir El Qalamum 96
51 cold
29
26
26
23
cold
cold
cold
cold
24
83
29
70
79
41
cold
30
27
23
56
31
24
24
43
81
64
62
69
77
42
51
166
I61
168
154
156
169
15x
158
93
163
70
79
250
234
158
161
159
205
166
164
I61
220
219
64
77
69
30x
St. Bishoy
St. Bishoy
St. Bishoy
Monastery
Monastery
I
f)W I>W
Med4
Med5
Med6
Med7
MedX
McdY
Med 10
El Qasr 4
Umm El Rakham
Hessien Saad
Angiela
Marsa Garguh
El Aitof
Sidi Barrani
47
26
4
4
I)W IIW
4
4
DW DW
4
DW
4
5
22.5
20.0
19.0
22.0
23.0
20.5
2 I .o
22.0
21 .o
24.0
70.0
6
4X.3
23.0
31.0
30.0
26.0
32.0
29.0
31.0
32.8
32.2
28.9
26.7
_
DW DW
T (“0
0
110
25
55
IO
2
117
95
60
DW
Med3
El Qasr
El Qasr 3
I
S
AW
Med2
Med
PW SL
I El Qasr 2
Mediferruneun
76
CAS30
Faraoun
Uyun Musa
Siwa22
‘Ain Hammam
Sinai
Birket
Makaryus
Siwa2
Bani Salama
Monastery
PW
Siwaf9 PW
DW
Siwalil
AW Ditch
Siwal6
AW
Siwal7
Siwa20
Baramus
Pl,
Siwal4
Siwa 15
Bir Hooker
Monastery
Near St. Bishoy Ceramic
St. Bishoy
Monastery
Wadi Na~run
Monastery DW
0
S
14
S
‘Ain Sukhna (Gulf of Suez)
0
S
13
0
0
S
D
51
ss
50
“0.
Sample
(Gulf of Suez)
‘Ain Sukhna
Sulphur
Spring
New Spring
Helwan
Helwan
Source
TABLE I (continued)
49
4.1
37
52
41
so
s5
50
5X
47
94
75
134
19
71
69
116
71
60
59
69
63
63
82
14
Ll, (“C) --
T?bKC:,
IS3
I60
191
IXX
76
177
200
210
201
cold
cold
X5
cold
52
4%
cold
cold
25
cold
85
232
63
63
33
47
46
24
22
28
28
25
26
26
25
21
38
153
84
x0
x9
141
145
123
136
147
151
129
130
120
X6
(“C)
Medl3
Med14
Medl5
Medl6
El Hawala
Harun
Haleit
Zawyet
Ras El Hekma
Fuka
Med20
Med2l
Med22
70
El5 75
77 93
Burg El Arab
Sidi Krir
Abu Yossef
Red Sea So. of Quseir
Red Sea at Marsa Alam
Birket Qarun
“cold”
indicates
at Marsa
Mediterranean
* The designation
Well no. 3
East Oweinat
Matruah
1T
Well no. 2
East Oweinat
that a magnesium
Siwa14A
2T
El8
River Nile at Luxor
River Nile at Asyut
(Faiyum
Oasis)
Medl9
El Daba 2
Musa Sinai
Medl8
I
El Daba
Uyun
Med17
Gaber
Sanyet
Basin
Medll
Medl2
El Maabdiya
Alam El Rum
correction
cannot
be applied
(see Fournirr
and Potter,
51
1979).
-50
44
_
54
31
55
~ 50
~62
41
64
63
33
82
53
97
95
44
47
42
_
22.8
_
_
20.0
21.0
22.0
22.0
21.0
20.0
20.5
22.0
20.0
19.0
63
sample
_
_
SL _
22.0 20.0
_
0 _
SL
0
I6
17
I2
26
24
ix
IX
I I:
4
I4
47
0 0
_ _
DW
DW
DW
DW
DW
DW
DW
DW
DW
DW
DW
DW lost
288
96
143
60
24
153
186
179
I82
89
167
I61
I78
234
91
265
149
229
92
149
cold
34
cold
60
24
36
70
cold
cold
cold
cold
cold
33
60
cold
33
cold
cold
33
cold
86
Fe. The samples Mexico within within
were sent to the State Soil and Water Testing
State University
for chemical
analyses.
The laboratory
Laboratory,
at New
work was completed
a few days of their shipment from Egypt so that most waters were analyzed three weeks of their collection in the field. The laboratory tests were
conducted
by standard
NaKCa-Mg
analytical
geotemperatures
Table I gives the SiO,,
for each of our samples.
ing those taken from the literature HOT SPRING
methods.
The sample
NaKCa,
locations
and
includ-
are given in Fig. 1.
DISTRIBUTION
Any discussion of hot springs must necessarily take into account the prevailing mean air temperature of the area in question. At Cairo, the mean air temperature is 22°C and temperature of Egypt
depth
may have a mean
data from the western ground
temperature
desert oasis indicate as high as 26°C.
that much
If one accepts
87
Waring’s
(1965) definition
temperature,
then
of a hot spring as one being 8.3”C (15°F)
temperatures
order to be classified
of Egyptian
as thermal.
Using
springs
this definition,
need
above mean air
to exceed
30-35°C
many of the thermal
reported by El Ramly (1969) cannot be strictly their temperatures (25-35°C) may be sufficient
classified as thermal, for some geothermal
Figure
(T > 30°C) that are considered
2 shows the wells (T > 35°C) and springs
be thermal.
Representative
thermal
springs
springs
probably
in Egypt
thermal
water
are located
owe their existence
along
chemistry the shores
to tectonic
is given
even though applications.
in Table
of the Gulf
(or volcanic)
heating
in
springs
to
II. All the
of Suez. These associated
with
the opening of the Red Sea-Gulf of Suez rift. Also shown in Fig. 2 is the Helwan sulphur spring (sample 51). This spring is located just south of Cairo and has been reported as having a temperature of 31.6”C (El Ramly, 1969). This spring exits into a bathing pool where obtaining a reliable temperature measurement is difficult and our measurement deeply circulating
of 28.9”C may be slightly low. This spring probably represents groundwater which has ascended to the surface along a fault zone.
In the Western “ thermal.” plot
of surface
Bahariya
Desert,
there
All of the occurrences temperature
are no springs of thermal
against
that
well depth
for wells
oases. Since all these wells are either artesian
agricultural
purposes,
the surface temperature
can be strictly
classified
as
water are from deep wells. Figure 3 is a from
or pumped
should adequately
the Kharga
and
continuously
for
reflect the bottom-
24 0
I1 200
I 400
Fig. 3. Plot of bottom Bahariya
oases.
I1 I I I I , I I 600 000 1000 1200 1400 DEPTH (ml
hole temperature
against
depth
for the deep artesian
wells from the Kharga
and
TABLE
II
Chemistry
of representative
Sample
Temp.
no. *
(“C)
waters
Ca
Na
Mg
K
Cl
co1
35.8
165.3
98.2
469.4
3.1
1038.4
0
E4
35
187.6
50.2
512.2
14.2
730.7
0
13
37.5
19.4
8.7
loo.5
30.1
20.6
0
14
38.0
25.8
Ii.7
66.0
26.6
5.3
0
17
35.0
35.7
21.3
57.2
35.2
102.1
0
87
41.1
15.6
15.3
45.1
6.6
73.4
0
3
CAS
thermal
90
42.2
13.8
14.3
48.3
7.0
81.5
0
94
39.0
14.2
6.8
22.3
3.5
1.8
0
96
42.8
9.2
7.0
13.6
4.7
0
0
103
38.9
Il.0
7.5
14.5
6.0
3.9
0
108
42.2
11.4
6.4
13.6
18.0
110
35.0
22.6
8. I
28.7
8.6
76
48.3
196.8
66.4
556.6
30
70.0
623.0
150.5
4272.9
74
32.8
479.4
255.0
1643.3
51
28.9
282.0
151.5
1382.4
24 -
0
I,
8
200
400
Fig. 4. Plot of bottom
/
/
I
0
0
9.9
0
8.6
904.1
0
151.3
7176.4
0
45.0
3442.3
0
29.3
2302.1
0
/ / L 3 I I
600
800 1000 DEPTH (ml hole temperature
1200
I400
against
depth
for the deep artesian
wells from the Dakhla
oasis.
89
HCO,
TDS
so4
PH
F
B
Fe
SiO z
208.7
587.9
2692
7.42
1.07
0.48
222.3
557.6
2200
7.34
0.16
0.41
0.19
239.2
73.0
492
7.96
0.18
0.90
< 0.10
14.0
194.0
61.5
280
7.98
0.08
1.14
< 0.10
12.5
109.8
86.5
468
7.46
0.06
0.45
< 0.10
13.0
86.6
25.0
264
7.10
0.05
0.36
0.23
18.5
95.2
21.1
268
6.93
0.05
0.34
0.35
18.5
46.4
61.5
140
6.50
0.03
< 0.20
0.93
19.0
47.6
50.0
108
6.72
0
< 0.20
0.10
18.0
65.9
32.7
141
6.93
0.02
< 0.20
< 0.10
16.5
52.5
46.1
148
6.65
0
-c 0.20
0.16
19.0
52.5
71.1
190
6.4
0.03
< 0.20
0.31
15.5
104.9
614.8
2844
-
0.73
1.05
2.98
27.0
< 0.1
34.0 16.9
135.4
1400.0
13909
6.98
1.84
2.21
0.11
42.5
162.3
922.2
8992
7.04
1.25
2.34
-c 0.10
20.0
272.1
845.3
7048
7.11
1.65
4.02
-c 0.10
32.0
l
Sample
no. refer to Fig. 1.
hole temperature
and can thus be used to estimate
squares fit to these data respectively. The former Morgan
the geothermal
gradient.
yield a slope and intercept of 16.5 mK/m value is consistent with the gradient data
et al. (1980) for northern
Egypt. The latter value is consistent
A least
and 26.O”C reported by with the mean
annual ground temperature of Egypt (26.6’C) calculated on the basis of the temperatures observed at the top of the water table for the hand-dug wells of the Eastern Desert. Thus, it appears that the hot wells of these oases owe their thermal nature
to heating
exploitable
The situation temperature-depth intercept anomalously escarpment
by a normal
geothermal
to low geothermal
gradient
and not to the presence
of
reservoirs.
at the Dakhla
oasis is somewhat
different.
data from wells at the Dakhla
of 11.8 mK/m
and
high temperatures forming the northern
29.4”C,
respectively.
A least squares
fit to the
oasis (Fig. 4) yields a slope and Further,
the wells that
show
are concentrated to the north (Fig. 5), near the boundary of the oasis. These data are most easily
reconciled by assuming that water, heated by a normal to low geothermal gradient, is ascending along conduits at the north end of the oasis and migrating south through the principal aquifers. Finally, it is worth noting that two regions of Egypt have shown thermal activity in the recent past. These are the extinct geysers on both sides of the Cairo-Suez highway and the Jebel Uweinat area of southwest Egypt (El Ramly, 1969).
90
200 -
290
50’
29010’
DAKHLA
-
25’50’
25O50’
OASIS
25O40’
-4
wells with respect
to the
25O40’
.
106
Fig. 5. Sketh map of the Dakhla escarpment
oasis showing
the locations
of the hottest
at the north end of the oasis.
SUBSURFACE
TEMPERATURE
ESTIMATES
The silica, NaKCa, and NaKCaMg geothermometers have been applied to all the samples collected as part of the present survey and the results are given in Table I. A quick scan of these data fails to reveal any samples with abnormally high geotemperatures.
Figure 6 shows the silica geotemperatures
for the thermal
subset
histogram
the silica geotemperatures
waters
included
Faraoun
(sample
beneath
a histogram
in this inventory.
showing
With
CAS 30) the thermal
the possible
exception
waters plotted of ‘Ain
as a
for all Hammam
waters give results that are comparable
to the
non-thermal waters for both the Eastern and Western Desert. Thus this geothermometer cannot be used to infer the presence of abnormally high subsurface temperatures. A similar conclusion is reached by analysis of the NaKCa and NaKCaMg geotemperatures. Figure 7 shows a plot (and least squares regression) of the NaKCa temperatures against SiO, temperatures for the thermal and non-thermal waters of the Eastern Desert. If the groundwater chemistry is being controlled by temperature dependent reactions, this plot should show a positive correlation. The data in Fig. 7 not only fail to show such a correlation but also fail to show elevated
91
WERN
DESERT
j--L
eii
WdTERS
.--I:
n= 88
40
THERMAL ”
meon=55.2 z 11.WC
ITeD”
=
17
=
57.314.i’C
WTERS
34.1 i 30 -
20 z e z z
IO-
g,
p-y
23 I
0
L
80
100
120
60 60 T6,02 V’C)
IO0
120
20
w
2
EJ_STERN
“0
20
Fig. 6. Histogram (bottom)
DESERT
deserts.
40
of silica geotemperatures Note that both the thermal
that the values are more compatible
for all groundwaters and non thermal
with low temperature
from
the western
(top)
and
waters yield similar geotemperatures,
rather
than high temperature
eastern and
hydrothermal
activity EASTERN
DESERT
WELL OR SPRING 1, T”ERMIL WELL 0R SPRlW l
,““I 0
20
40
”
60 T&O2
Fig. 7. Plot of NaKCa Desert.
s ’
80 (W
)
L
100
geotemperatures
Note the lack of any obvious
s
“1
120
I40
against
silica geotemperatures
high temperature
geothermal
for groundwaters
fluids.
of the Eastern
92
01 0
I”“’ 20
I’ I ( I ” 1 60 80 100 120 140 TS,02 VT)
40
Fig. 8. Plot of NaKCaMg Desert.
geotemperatures
Note the lack of any obvious
against
silica geotemperatures
high temperature
geothermal
for groundwaters
of the Eastern
fluids.
geotemperatures for the thermal waters relative to the non-thermal waters. A more realistic plot is obtained by plotting (with a least squares regression) the NaKCaMg temperatures the value
against of applying
the SiO, temperatures the magnesium
(Fig. 8). This improvement
correction,
underscores
at least for this data
set. Still.
however, there is no tendency for the thermal waters to give higher geotemperatures than the non-thermal waters and we thus conclude that there is no evidence from the geothermometry associated
TABLE
data
to support
the existence
with any of the thermal
springs
of a major
geothermal
of Egypt.
III
Heat flow estimates
of Egypt based on the silica heat flow technique
Location
Number samples
of
Ts,o, (“C)
r, (“C)
4 (mW m-‘)
Traditional (mW mm’)
Eastern
Desert
44
75.4*
15.3
21.9
12.2
77.6 rl
Kharga
Oasis
13
47.55
2.4
26.0
32.1
40-45
12
54.8*
2.8
26.0
43.0 46.1
Bahariya
Oasis
18
55.1 k
4.2
24.4
21
55.4*
17.3
21.2
51.0
22 7
60.3 k 13.7
26.4
50.6
74.7 * 19.4
26.0
12.7
Cairo Area
4
24.9
96.0
Sinai (West Coast)
4
89.2 + 13.4 73.8 + 14.6
25
72.8
Dakhla
anomaly
Oasis
Mediterranean
Coast
Siwa Oasis Wadi Natrun
a Morgan
et al. (1980).
’ Morgan
et al. (1976).
80-100
.J
b
q
93
SILICA
HEAT FLOW
Swanberg and Morgan (1979, 1980) have shown that it is possible to use the silica content of groundwaters to estimate regional heat flow. Normally, this technique is used to supplement where
existing
heat flow data by providing
additional
coverage
in areas
traditional data are sparse. The appropriate equation is q = (7”,o, - q;,)/m in “C, T, is the mean Ts,o is the quartz conductive silica geotemperature
where annual ground temperature in “C, m is 670°C m2 W-’ and q is heat flow in mW m -l. Table III gives the silica heat flow data for various parts of Egypt. In general the agreement between the silica and the traditional heat flow data is good (Swanberg and Morgan, 1980). Eastern Desert heat flow averages 72.2 mW mp2 which is higher than is normally observed in stable platform areas and implies a major heat flow anomaly in the Precambrian of eastern Egypt. The heat flow throughout the western desert oases and along the Mediterranean coast is low ( < 51 mW mm’). On the basis of a very scanty data set, it would appear that high heat flow may exist from the Gulf of Suez area as far west as the Cairo-Faiyum-Wadi Natrun area. CONCLUSIONS
The use of silica estimating
regional
times normal) Hammam
geotemperatures
exists on the border
Faraoun,
of groundwater
heat flow in Egypt. A relatively
is a valuable
technique
for
high heat flow zone (1.7 to 2.3
of the Gulf of Suez and this area contains
‘Ain
the hottest spring in Egypt at 70°C. This zone, which is the most
favorable for geothermal exploration and development, could possibly extend as far west as Cairo and the Faiyum oasis and Wadi Natrum areas based on the groundwater
silica data, extinct
The Eastern
Desert
in general
Geysers
and the historic
has a moderately
seismicity
high regional
of these areas. heat flow of about
75 mW rnp2 based on both the silica data and traditional measurements (Morgan et al., 1980). This area should also be favorable for geothermal discovery although only one thermal well was located during the present study. The Western
Desert has low regional
heat flow ( < 50 mW me2)
and correspond-
ingly low geothermal potential. However, many of these oases (perhaps all of them) are underlain by deep artesian aquifers which produce high quality water in the 30-45°C
temperature
range. These aquifers
may have low temperature
potential. A similar deep artesian aquifer has been observed E4, Table I, Fig. 2) in the Eastern Desert between the River hills. Therefore, it is possible that much of the area immediately also have low temperature geothermal potential. There is no that a major high temperature geothermal field underlies any
geothermal
at El Laqeita (sample Nile and the Red Sea east of the Nile may geochemical evidence area we visited.
94
ACKNOWLEDGEMENTS
The present study could not have been completed without the considerable assistance of Dr. Rushdi Said, and Mr. Gala1 A. Moustafa, Consecutive Directors of the Egyptian
Survey and Mining
Mr. A.A. El-Sheriff, Daggett,
Authority.
Mr. A.A. El-Sayed,
and Mr. T. Roemer
We also acknowledge
Mr. S.F. Hennin,
Mr. N.Z. Basta, Mr. Y.S. Melic, Dr. P.H.
for their help with the data collection.
The work was
funded by the U.S. National Science Foundation through grant numbers EAR7723354 and INT78-16649 from the Earth Sciences program and the Office of International
Programs,
respectively.
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