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Oxygen and sulfur isotopic composition of the sulfate ions from mineral and thermal groundwaters of Poland
Journal of Hydrology, 24 (1975) 271--282 © North-Holland Publishing Company, Amsterdam -- Printed in The Netherlands
OXYGEN AND SULFUR ISOTOPIC COMPOSITION OF THE SULFATE IONS FROM MINERAL AND THERMAL GROUNDWATERS OF POLAND
GIANNI CORTECCI and JAN DOWGIALLO Laboratorio di Geologia Nucleare, Universitb di Pisa, Pisa (Italy) Laboratory of Hydrogeology, Institute of Geological Sciences, Polish Academy of Sciences, Warsaw (Poland) (Accepted for publication June 19, 1974)
ABSTRACT Cortecci, G. and Dowgiallo, J., 1975. Oxygen and sulfur isotopic composition of the sulfate ions from mineral and thermal groundwaters of Poland. J. Hydrol., 24: 271--282. This paper gives the 1sO and the uS contents of the sulfate dissolved in some mineral and thermal groundwaters in northwest Poland, in the Carpathians, in the Carpathian foredeep and in the Sudety Mountains. The oxygen isotopic composition of sulfate ions is compared with the 180/1+O and D/H ratios of the environmental waters. From the results obtained, the oxygen and sulfur isotopic composition of the sulfate ions seems generally due to a sulfate bacterial metabolic activity, which has enriched the residual sulfate in the heavy isotopes. No correlation exists between the ~ ~80(SO~-) values and the other parameters, such as depth and age of aquifers, outflow temperature, total salinity, sulfate concentration, 5 ~80 and 5 D values of the environmental waters, except for the SO~--water pairs with 5180(H20) > 0. In this case there is a positive 6 ~sO(SO~-)--6 ~80(H20) correlation which proves a partial isotopic equilibration and excludes for these waters an admixture with relatively recent infiltration waters. The positive ~80 contents of some waters {from +3.0 to +6.7%0) analysed and discussed previously by Dowgiallo (1973) have been newly examined at the light of the experimental results recently published on the oxygen and hydrogen isotopic fractionation in the ultrafiltration processes of water (or aqueous solution) by compacted clay.
INTRODUCTION M a n y p a p e r s h a v e so f a r b e e n p u b l i s h e d o n t h e o x y g e n a n d sulfur i s o t o p i c c o m p o s i t i o n o f n a t u r a l s u l f a t e - w a t e r s y s t e m s ( C o r t e c c i a n d Longinelli, 1 9 7 0 ; LongineUi a n d C o r t e c c i , 1 9 7 0 b ; Cortecci, 1 9 7 3 a ; S c h w a r c z a n d C o r t e c c i , 1 9 7 4 ) a n d o f e v a p o r i t i c sulfates (Sakai, 1 9 7 2 ; Cortecci, 1 9 7 3 b ) . Studies o n the oxygen isotopic behaviour of the sulfate-water system and on the bacterial f r a c t i o n a t i o n o f o x y g e n a n d s u l f u r in t h e r e d u c t i o n o f s u l f a t e a n d in t h e oxidat i o n o f sulfide a n d sulfur h a v e also b e e n carried o u t ( L l o y d , 1 9 6 7 , 1 9 6 8 ; M i z u t a n i a n d R a f t e r , 1 9 6 9 ) . T h e n t h e m e a s u r e m e n t o f t h e 180 a n d ~ S c o n t e n t s o f t h e s u l f a t e dissolved in u n d e r g r o u n d w a t e r s m a y give s o m e i n f o r m a t i o n o n
272
its origin and on the sulfate--sulfide reduction--oxidation processes u~u~leci. Amongst those analysed here, the waters showing 5180 ~ 0 may be considered closed systems, and, accordingly, an eventual oxygen isotopic positive correlation with the dissolved sulfates and the environmental waters would have proved the lack of a mixing with recent infiltration waters.
Experimental procedures The procedure used for the preparation of samples for measuring the 180(SO~-) was the same as that previously reported (Cortecci and Longinelli, 1968). The oxygen isotopic analyses of the resulting BaSO4 samples were carried out using the graphite-reduction technique as described in previous papers (Longinelli and Craig, 1967; Longinelli and Cortecci, 1970a). The sulfur-isotopic analyses were carried out using the technique as described by Ricke {1964). The oxygen and hydrogen isotopic data of all water samples reported here have already been published by Dowgiallo (1973). The isotopic ratios are given in the customary 5 notation, ~ being defined by the equation: 6 = (Rsample/Rstandard - - 1 ) • 1 0 3, in % , where R is the O18/O16 or S~/S 3~ isotopic ratios. The oxygen and hydrogen isotopic results are reported relative to the Standard Mean Ocean Water (SMOW) as defined by Craig (1961a). The standard deviation of the ~ ~80(SO~-) measurement is + 0.1% 0. The 8 ~S(SO~-) values are given relative to meteoritic sulfur standard {Canyon Diablo troilite) (Thode et al., 1961; Ault and Jensen, 1962; Jensen and Nakai, 1962). R E S U L T S AND DISCUSSION
The results obtained and reported in the Tables I, II, III and IV concern samples from different areas of the Poland: Carpathians, Carpathian foredeep, northwest Poland and Sudety Mountains localities (Fig.l).
Carpathian samples Only the 180/160 ratios of the sulfate dissolved in these waters have been measured. The results and other details are reported in Table I. DowgiaUo (1973) reports that these waters may be separated in three groups. To the first belong waters with 8180 not higher than --10°~0 and 8 D not higher than --70%. The low content in heavy isotopes suggests they are infiltration waters recharged from relatively high areas. To the second group belong waters with ~ 180 values from --9 to --2% and ~ D values from --60 to --30%. The presence of an admixture of marine relict water may be assumed here. The waters with 5 '80 ~ 0 have been reported as the result of an isotopic exchange with wall rock oras allochthonic relict waters of evaporating basins., other than the flysch ones. On this suggestion we return critically later The waters show mineralization values lower than that of modern mean sea
273
GDANSK
kLIN S wi n o ujscie..c~-""~K o ~ob r z e9 ~mien
OL.oSZTYN
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o
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./-+.,+I
.+Z ~e
AN
~R SZAWA
o LUBLIN
.2"/~.. Ci~ptice
KIELCE O
\oo~,oL E •%e .¢-,,., • .e'$.. '%~..
\
Busko
KATOWICE o
/
Sotec
,,~"* 2.
KRAKOWJ~
"~"
,,.,oo
"~,
v~.e~
. <_:
~
~"
"%.
..Mu..,o.,
T~.b-"s.~ 9 +,~~,.uw
.~"
\+
.~,, ,~-. t~r .% Fig.1. T h e m a p shows the Poland localities f r o m which the samples ~ave been collected.
water (about 35 g/l), low sulfate concentration and 8 '80(SO~-) values ranging from +12°/00 to +17°&, with a mean value of +14.8%0 relative to SMOW. For the samples with 5180(H20) < 0 there is no correlation of ~ 180(SO~-) values with the isotopic composition of water, the chemical parameters, the outflow temperature, the age and the depth of the aquifers. The samples with 8 lSO(H20) > 0, outflowing from Upper Cretaceous and Tertiary flysch aquifers, show relatively high mineralization values. There is a positive correlation between the 5180(H20) > 0 and the 8 xso(so24 -) of dissolved sulfate (Fig.2). This correlation, with a slope of 0.3, is clearly due to an oxygen isotopic exchange and proves that these waters have not been mixed with recent infiltration waters, which would have shown no such correlation. F~om this point of view is significant that water samples from the same locality, i.e. Szczawnica and Wysowa, show markedly different ~ ~SO(H:O) values. In the case of the Szczawnica sulfate samples, the less positive 8180 = +11.8°/00 may reflect an isotopic exchange with a more negative water
Zakopane Zakopane Rabka Rabka Rabka Rabka Rabka Szczawnica Szczawnica Zegiestow Zegiestow Muszyna Muszyna Krynica Krynica Krynica Krynica Wysowa Wysowa Rymanov
Locality
IG1 IG1 Warzelnia Helena Boleslaw 18 19 Dzikie Magdalena Andrzej Anna Milusia Grunwald Slotwinka Mieczyslow Zuber I Zuber III Bronislawa II Aleksandra Odw. 1
Well name or No.
1,560 1,560 46 460 102 120 95 0.3 3.45 280 1.2 111 1.5 2 65 810 936 18 100 470
Triassic Triassic Tertiary Tertiary Tertiary Tertiary Tertiary U. Cretaceous U. Cretaceous Tertiary Tertiary Tertiary Tertiary Tertiary Tertiary Tertiary Tertiary U. Cretaceous U. Cretaceous Tertiary
36.0 36.0 10.5 12.2 10.1 10.5 13.5 10.8 10.8 9.9 8.8 9.0 9.3 7.9 9.1 11.1 10.3 9.2 12.1 16.1
temp. (°C)
depth (m)
age
Water's
Aquifer's
328 328 16,713 20,623 17,629 12,138 18,011 6,664 25,034 2,642 2,182 3,888 3.430 4,039 4,752 24,655 27,985 3,941 24,500 22,575
total salinity (ppm) 50 50 38 29 15 36 60 67 40 28 39 26 37 27 31 57 67 30 34 40
[SO~- ] (ppm)
---61.7 --55.8 --64.3 --27.6 --33.8
--70.1 --70.1 --30.9 --20.5 --33.0 --20.8 --31.8 --62.3 --35.6 --77.1 --74.7 --76.3 --71.8 --78.1
~ D(H~O
--10.6 --11.1 +2.8 +5.7 +2.3 +6.3 +3.1 --7.4 +3.8 --11.1 --10.9 --10.7 --10.6 --11.2 --11.1 --7.4 --7.5 --8.4 +6.6 +2.2
5 ~80(H20)
+16.1 +16.9 +15.2
+15.0 +14.7 +15.1 +15.5 +15.1 +15.8 +15.3 +11.8 +15.4 +13.2 +12.3 +15.5 +15.0 +15.2 +13.9 +15.2
6 ~sO(SO~-)
(1973).
* The ~ ~sO and 6 D values of the waters reported in this and in the other tables are taken from Dowgiallo and Tongiorgi (1972) and Dowgiallo
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
4 5
1 2 3
Sample No.
Isotopic composition of water and dissolved sulfate samples from the Carpathians*
TABLE I d~
275
17
Q
o o
16
o
O +x++*
o
o
~" %"
15
O~ 0
14
0
13
OiI
oo
•
•
o
0 12
o
1 I L JO J I L L J I I I L I I L I L L I L - 1 2 - 1 1 -1 - 9 - 8 - 7 - 6 - 5 - 4 - 3 - 2 -1 0 0 + 1 +2 +3 +4 +5 +6 +7
~'ao(Hzo )
Fig.2. Relationship among the 8 mO(SO~-) and 5 '80(H20) values. White circles, Carpathian samples; black circles, Carpathian foredeep samples; white squares, northwest Poland samples; black squares, Sudety Mountains samples.
or a mixing o f t w o isotopically different sulfates at least. The isotopicaUy more negative of this sulfate admixture may derive from the oxidation of sulfide compounds, resulting an impoverishment both in 180 and US isotopes. The ~ mO(SO~-) values are higher than that o f the present-day sea-water sulfate (+9.5°o) (Longinelli and Craig, 1967; Molcard et al., 1973). Assuming that the oxygen isotopic composition of the sea-water sulfate has varied little with geological time, and this assumption seems true up to and including the Tertiary (Sakai, 1972; Solomon et al., 1972), the 'sO contents of the analysed sulfate ions may reflect some isotopic enrichment processes, like the bacterial sulfate metabolism (Lloyd, 1967, 1968; Mizutani and Rafter, 1969) and the precipitation of the sulfate ions from the solution as gypsum or anhydrite (Lloyd, 1968). These processes enrich the residual sulfate and the solid phase both in 180 and in uS and may occur at the same time in an evapoxitic basin. It has to be underlined, however, that evaporatic conditions are not characteristic for the flysch basin, except some local phenomena reported by Ksiazkiewicz (1962).
Carpathian foredeep samples The samples c o m e from an area of marine Miocene sediments. The isotopic results and other details are shown in the Table II. As reported b y Dowgiallo (1973), the mineral waters occurring there may contain a lower (Busco, Solec samples) or higher (Debowiec sample) a m o u n t of relict marine water. The Dobowiec sample, which shows an isotopic composition very close to that of present-day sea-water, may be assumed as a relict Miocene sea-water. Its Na-C1, -Br and -I chemical contents and its total salinity agree with a marine origin, b u t the sulfate concentration is much lower than that of the present-day sea (about 2,700 ppm). Evaporitic conditions with CaSO4 precipitation, diagenetic bacterial reduction of sulfate ions and
Locality
Debowiec Busko Solec Solec
Sample No.
1 2 3 4
2 15 Szyb 2
Well name or No.
500 500 120 155
Miocene Maim U. Cretaceous U. Cretaceous
12.0 14.0
temp. (°C)
depth (m)
age
Water's
Aquifer's
31,869 22,861 21,074
total salinity (ppm)
10 920 3,080
[SO~- ] (ppm)
--3.6 --47.9 --39.3 --31.5
D(H20)
Isotopic composition of sulfate--water pairs from marine Miocene sediments (Carpathian foredeep)
TABLE II
0.0 --6.6 --5.7 --2.4
51'O(H20)
+14.7 +15.3 +12.9 +16.8
'~o(so]-)
+33.4 +29.7 +34.0
~3, S
O~
t~
277 dilution by infiltration water may account for the observed low SO~- content. So, the 81sO and 5 D values of the water included in the sediments probably in the Miocene time, should be higher than those meAsl]r~.d, due to ancient evaporitic conclitions. A mixing with more negative infiltration water may explain the observed isotopic values. The 'SO contents of the dissolved sulfates are close to those observed for the Carpathian water sulfates. The US contents are higher than that of presentday sea-water sulfate (6 uS = +20.0o/00) and very far from the 8 US values estimated for the ancient ocean sulfates (Thode and Monster, 1965; Holzen and Kaplan, 1966}. As shown in Fig.3, there is a positive correlation amongst the 180 and 34S contents of the analysed sulfates' and it, together with the high 5180 and 5 uS values, proves a bacterial elaboration of the dissolved sulfates. The Solec samples contain H2S and show different isotopic values both of the water and of the sulfate: to more negative ~ 180(H20) correspond more negative 61sO and 5 '8S of the dissolved sulfate. It may be due to an admixture of more positive sulfate with a 8180 value close to +17%0 with a more negative sulfate formed by H2S oxidation into a surface and oxygenated water.
18 17 Q
16
,,o
15
Q O10 11 Q9
3 Q2
14 '~3
,~ 2'0 ;5 36 3'~ ,6 ~'s(s0~') Fig.3. 5 ~ S(SO~- ) relative to ~ ~80(SO~- ). Black circles,Carpathian foredeep samples; white squares, northwest Poland samples.
Northwest Poland samples As reported by Dowgiallo and Tongiorgi (1972) these brines from the Mesozoic in northwest Poland may derive from highly saline fossil waters by dilution with recent meteoric waters. The ti 180 and 8 US values (see Table III) are higher than those of m o d e m sea-water sulfate and show a positive correlation (Fig.3) due, also in this case, to a sulfate reductive bacterial activity. No correlations occur with the isotopic quantity of the dissolved sulfate and the other parameters. Only the sample coming from Miedzywodzie Triassic aquifer shows a ~ US lower than that of
Locality
Swinoujscie Miedzywodzie Kam. Pomorski Kolobrzeg Kolobrzeg Kolobrzeg Ciechocinek Ciechocinek Cieehocinek Ciechocinek Ciechoeinek
Sample No.
1 2 3 4 5 6 7 8 9 10 11
5 IG1 Odw. 18 7 B1 8b 11 14 16 18
Well name or No.
185--260 1,015 415 2 41 102 34 414 757 1,364 1,450 Triassic Liassic Quaternary Dogger Dogger Maim Dogger Liassic Liassic Liassic
L. Cretaceous
27.5 32 32
19 10 10 10.5 11
temp. (°C)
depth (m)
age
Water's
Aquifer's
96,426 36,317 45,000 43,522 53,974 3,811 38,881 42,925 63,057 71,794
total salinity (ppm)
Isotopic composition of sulfate--water systems from the Mesozoic in northwest Poland
TABLE III
[ SO~- ]
244 360 44 920 76 496 604
2,560 244
(ppm)
--40.0 --39.0 --38.5
--44.0 --61.0
--56.0
D(H,O)
--7.4 --7.0 --7.2 --5.4 --8.0 --5.0 --4.7 --4.8 --4.6
6 I$O(H20)
+13.6 +13.6 +15.8 +16.5 +16.1 +16.4 +15.1 +16.3 +14.8 +15.4 +15.4
~180(SO~-)
+34.4 +29.0 +27.7 +25.6
+14.9 +31.8 +38.2 +32.2 +32.2
~]4S
Q0
t~
279
the present-day sea-water sulfate. The 6 uS value agrees with the probable value of the Upper Triassic sea-water sulfate (+13.1°/00) (Thode and Monster, 1965; Holzen and Kaplan, 1966; Nielsen, 1966). Assuming for this sample a low enrichment both in 180 and uS by means of bacteria, the 51so value of the Upper Triassic sea-water sulfate should be close to the m o d e m one. Sudety Mountains samples
The low content of heavy isotopes in the Sudetic waters (Table IV) shows f,heir infiltration origin (Dowgiailo, 1973). The waters from Carboniferous granitic aouifer show the lowest 5~80 (SO~-) values and the lowest salt contents. Positive ~ lSO(H20) values o f some Carpathian waters and their implications
As shown in Table I, several waters from Tertiary flysch aquifers show 5~so > 0. In the Fig.4 are shown the ~ 'sO-~ D correlations of the waters with 5180 ~< 0 and with 51so > 0. The 5~so ~< 0 values range from -11.0 to 0.0% 0, with a 5D range from - 7 7 to -3.6%0. All the points with 6~so ~< 0 are close to a straight line with a slope of 6.1, which agrees well with evaporation and wallrock isotopic exchange processes. As regards the samples with ~ 1so > 0, the ~ D-~ lSO straight line intercepts the ~ D--~ 1So line of meteoric waters found by craig (1961b) at ~ 1So = --9% and 5 D = --650/oo. The slope of 2.5 of this line excludes the evaporation process for the observed 180 enrichment. The slope becomes 3.1 if one assumes for the meteoric water in t h e Carpathian area the lowest isotopic values measured for the Carpathian water samples (6180 --11% and 5 D = --770/0o). This last slope agrees perfectly with that found by Coplen and Hanshaw (1973) in their water and solution ultrafiltration by compacted clay membrane experiments. An admixture of an isotopicaily very positive water with meteoric waters seems to be excluded by the very high ~ 1so value of this positive water =
0 •O10
o
"~
~
~
•
o
30
50 60 70 80 i
i
i
i
1
I
1
I
i
i
i
i
I
i
i
I
i
I
I
I
-12-11-10 - 9 -8 -7 - 6 - 5 - 4 -3 -2 -1 0.0+1 +2 +3 +4 +5 +6 +7
~ leO(H=O)
Fig.4. Water 5 D--81sO relationships. F o r the s y m b o l s see Fig.2. The straight line with slope 8 represents the meteoric waters (Craig, 1961b); for the other lines see text.
Locality
Cieplice Cieplice Cieplice Cieplice Cieplice Polanica Polanica
Sample No.
1 2 3 4 5 6 7
Marysienka Sobieski Nowe Waclaw Basenowe Damskie Wilka Pilniawa P300
Well name or No.
25 4.9 60 4.5 2 34 123 Carboniferous Carboniferous Carboniferous Carboniferous Carboniferous U. Cretaceous U. Cretaceous 23.7 22.6 37.6 18.1 43.8 11.5 4.5
(°c)
temp.
depth (m)
age
Water's
Aquifer's
Isotopic composition of sulfate--water pairs from Sudety Mountains
TABLE IV
661 513 651 689 668 1,605 2,692
total salinity (ppm)
[so~-]
166 73 160 154 179 34 63
(ppm)
--68.8 --67.6 --69.1 --65.5 --70.7
,~D(H20)
--10.5 --9.9 --10.4 --10.0 --10.6 --9.8
6~80(H20)
+13.0 +13.2 +11.6 +11.3 +11.7 +14.9 +14.4
6 "o(so,~-)
tO O0
281
(5 'so > 6.6°~0}: Longinelli and Nuti (1968) measuring the oxygen isotopic composition of phosphate from well-preserved fossil marine organism, propose for the Tertiary Mediterranean and for littoral areas of larger basin waters '80 values of +2.0 to +3.0°o relative to the mean m o d e m ocean water with a 5 '80 close to zero. Furthermore, their origin from meteoric infiltration waters submitted to a strong oxygen isotopic exchange with wall rocks is excluded by the relatively high 5 D values. Thus, the '80 contents of these waters and their 5 D---5180 slope are probably due to an isotopic fractionation by ultrafiltration through compacted clayey sediments: this process enriches the water of the residual solution in '80 and D isotopes. CONCLUSIONS
The analysed brines, thermal and cold mineral waters come from various old aquifers of different areas of Poland. Some of these waters are an admixture of relict sea water with infiltration meteoric water. The oxygen and the sulfur isotopic compositions of the analysed sulfate are higher than the m o d e m sea-water sulfate. These high isotopic contents and the positive 8180--~ US correlation may reflect a strong bacterial sulfate reductive activity in the water and in the bottom sediments of lagoons before and during the diagenesis. The dissolved sulfate may be syngenetic with the environmental water in the case of waters showing high or relatively high SO~- concentrations and positive or slightly negative 5 'sO values. For low SO~- concentrations and low 8180 and ~ D values of the waters, the dissolved sulfates may derive from leaching of sulfatic material disseminated in the rocks by infiltration waters. As regards the waters with 5 '80 > 0, the slope of the 8 '80--5 D relationship agrees very well with that found in ultrafiltration experiments using compacted clay as a membrane, and these waters can be explained as the residual ones in ultrafiltration processes through clays and shales. ACKNOWLEDGEMENTS
Thanks are due to E. Tongiorgi for helpful discussions. We are grateful to H. Nielsen who analysed the sulfates for uS at the Geochemischen Institut der Universit~it, GSttingen.
REFERENCES Ault, W.U. and Jensen, M.L., 1962. Summary of sulfur isotopic standards. In: M.L. Jensen (Editor), Biogeochemistry of Sulfur Isotopes, pp.16--19 Coplen, T.B. and Hanshaw, B.B., 1973. Ultrafiltration b y a compacted clay membrane. I. Oxygen and hydrogen isotopic fractionation. Geochim. Cosmochim. Acta, 37 : 2295-2310
282
Cortecci, G., 1973a. Oxygen-isotope variations in sulfate ions in the water of some Italian lakes. Geochim. Cosmochim. Acta, 3 7 : 1 5 3 1 - - 1 5 4 2 Cortecci, G., 1973b. Analisi isotopica di una formazione evaporitica del Miocene Superiore. Rend. Soc. Ital. Mineral. Petrol., 2 9 : 1 - - 1 8 Cortecci, G. and Longinelli, A., 1968". Oxygen-isotope measurements of sulfate ions separated from diluted solutions. Earth Planet. Sci. Lett., 4 : 3 2 5 - - 3 2 7 Cortecci, G. and Longinelli, A., 1970. Isotopic composition of sulfate in rainwater, Pisa, Italy. Earth Planet. Sci. Lett., 8 : 3 6 - - 4 0 Craig, H., 1961a. Standard for reporting concentrations of deuterium and oxygen-18 in natural waters. Science, 1 3 3 : 1 8 3 3 - - 1 8 3 4 Craig, H., 1961b. Isotopic variations in meteoric waters, Science, 1 3 3 : 1 7 0 2 - - 1 7 0 3 DowgiaUo, J., 1973. Wyniki badin skladu isotopowego tlenu i wodorn wodach podziemnych Polski poludniowej (Results of measurements o f the oxygen and hydrogen isotopic composition of groundwaters of South Poland). Inst. Geol. Buil., 2 7 7 : 3 1 9 - - 3 3 8 Dowgiallo, J. and Tongiorgi, E., 1972. Isotopic composition of oxygen and hydrogen in some brines from the Mesozoic in northwest Poland. Geothermics, 1 : 67--69 Holzen, W.T. and Kaplan, I.R., 1966. Isotope geochemistry of sedimentary sulfates. Chem. Geol., 1 : 9 3 - - 1 3 5 Jensen, M.L. and Nakai, N., 1962. Sulfur isotope meteorite standards results and recommendation. In: M.L. Jensen (Editor), Biogeochemistry of Sulfur Isotopes, pp.30--35 Ksiazkiewicz, M., 1962. On the occurrence of gypsum in the Magura flysch. Bull. Acad. PoL Sci., Set. Sci. Geol. Geogr. (Varsovic), 10(1) Lloyd, R.M., 1967. Oxygen-18 composition of oceanic sulfate. Science, 1 5 6 : 1 2 2 8 - - 1 2 3 1 Lloyd, R.M., 1968. Oxygen isotope behavior in the sulfate-water system. J. Geophys. Res., 7 3 : 6 0 9 9 - - 6 1 1 0 Longinelli, A. and Cortecci, G., 1970a. ComPosizione isotopica dell'ossigeno nei solfati. Tecniche di misura. Rend. Soc. Ital. Mineral. Petrol., 2 6 : 7 3 3 - - 7 4 3 Longinelli, A. and Cortecci, G., 1970b. Isotope abundance of oxygen and sulfur in sulfate ions from river water. Earth Planet. Sci. Lett., 7 : 3 7 6 - - 3 8 0 Longinelli, A. and Craig, H., 1967. Oxygen-18 variations in sulfate ions in sea water and saline lakes. Science, 1 5 6 : 5 6 - - 5 9 Longinelli, A. and Nuti, S., 1968. Oxygen-isotope ratios in phosphate from fossil marine organisms. Science, 1 6 0 : 8 7 9 - - 8 8 2 Mizutani, Y. and Rafter, T.A., 1969. Bacterial fractionation of oxygen P-~d sulfur isotopes in the reduction o f sulfate and in the oxidation of sulfur. N. Z. J. Sci., 1 2 : 6 0 - - 6 8 Molcard, R., Cortecci, G. and Noto, P., 1973. Isotopic analysis of the deep staircase structure in the Tyrrhenian Sea. Unclassified SACLANTCEN Memorandum SM-24 Nielsen, H., 1966. Schwefelisotope in marinem Kreislauf und das ~ 34S der friiheren Meere. Geol. Rundsch., 5 5 : 1 6 0 - - 1 7 2 Ricke, W., 1964. Preparation von Schwefeldioxid zur massenspektrometrischen Bestimmung des Schwefel-Isotopen-Verhiiltnisses ~ S/~S in natiirlichen Schwefelverbindungen Z. Anal. Chem., 1 9 9 : 4 0 1 - - 4 1 3 Sakai, H., 1972. Oxygen isotopic ratios of some evaporites from Precambrian to Recent ages. Earth. Planet. Sci. Lett., 1 5 : 2 0 1 - - 2 0 5 Schwarcz, H.P. and Cortecci, G., 1974. Isotopic analyses of spring and stream water sulfate from the Italian/kips and Apennines. Chem. Geol. 1 3 : 2 8 5 - - 2 9 4 Solomon, M., Rafter, T.A. and Dunham, K.G., 1971. Sulfur and oxygen isotope studies in the northern Pennines in relation to ore genesis. Appl. Earth. Sci., 8 0 : 3 2 5 9 - - 3 2 7 5 Thode, H.G. and Monster, J., 1965. Sulfur-isotopic geochemistry of petroleum, evaporites and ancient seas. Reprinted from: Fluids in Subsurface Environments. A Symposium. Am. Assoc. Petrol. Geol., Mem., 4 : 3 6 7 - - 3 7 7 Thode, H.G., Monster, J. and Dunford, H.G., 1961. Sulfur isotope geochemistry. Geochim. Cosmochim. Acta, 2 5 : 1 5 9 - - 1 7 4
OXYGEN AND SULFUR ISOTOPIC COMPOSITION OF THE SULFATE IONS FROM MINERAL AND THERMAL GROUNDWATERS OF POLAND
GIANNI CORTECCI and JAN DOWGIALLO Laboratorio di Geologia Nucleare, Universitb di Pisa, Pisa (Italy) Laboratory of Hydrogeology, Institute of Geological Sciences, Polish Academy of Sciences, Warsaw (Poland) (Accepted for publication June 19, 1974)
ABSTRACT Cortecci, G. and Dowgiallo, J., 1975. Oxygen and sulfur isotopic composition of the sulfate ions from mineral and thermal groundwaters of Poland. J. Hydrol., 24: 271--282. This paper gives the 1sO and the uS contents of the sulfate dissolved in some mineral and thermal groundwaters in northwest Poland, in the Carpathians, in the Carpathian foredeep and in the Sudety Mountains. The oxygen isotopic composition of sulfate ions is compared with the 180/1+O and D/H ratios of the environmental waters. From the results obtained, the oxygen and sulfur isotopic composition of the sulfate ions seems generally due to a sulfate bacterial metabolic activity, which has enriched the residual sulfate in the heavy isotopes. No correlation exists between the ~ ~80(SO~-) values and the other parameters, such as depth and age of aquifers, outflow temperature, total salinity, sulfate concentration, 5 ~80 and 5 D values of the environmental waters, except for the SO~--water pairs with 5180(H20) > 0. In this case there is a positive 6 ~sO(SO~-)--6 ~80(H20) correlation which proves a partial isotopic equilibration and excludes for these waters an admixture with relatively recent infiltration waters. The positive ~80 contents of some waters {from +3.0 to +6.7%0) analysed and discussed previously by Dowgiallo (1973) have been newly examined at the light of the experimental results recently published on the oxygen and hydrogen isotopic fractionation in the ultrafiltration processes of water (or aqueous solution) by compacted clay.
INTRODUCTION M a n y p a p e r s h a v e so f a r b e e n p u b l i s h e d o n t h e o x y g e n a n d sulfur i s o t o p i c c o m p o s i t i o n o f n a t u r a l s u l f a t e - w a t e r s y s t e m s ( C o r t e c c i a n d Longinelli, 1 9 7 0 ; LongineUi a n d C o r t e c c i , 1 9 7 0 b ; Cortecci, 1 9 7 3 a ; S c h w a r c z a n d C o r t e c c i , 1 9 7 4 ) a n d o f e v a p o r i t i c sulfates (Sakai, 1 9 7 2 ; Cortecci, 1 9 7 3 b ) . Studies o n the oxygen isotopic behaviour of the sulfate-water system and on the bacterial f r a c t i o n a t i o n o f o x y g e n a n d s u l f u r in t h e r e d u c t i o n o f s u l f a t e a n d in t h e oxidat i o n o f sulfide a n d sulfur h a v e also b e e n carried o u t ( L l o y d , 1 9 6 7 , 1 9 6 8 ; M i z u t a n i a n d R a f t e r , 1 9 6 9 ) . T h e n t h e m e a s u r e m e n t o f t h e 180 a n d ~ S c o n t e n t s o f t h e s u l f a t e dissolved in u n d e r g r o u n d w a t e r s m a y give s o m e i n f o r m a t i o n o n
272
its origin and on the sulfate--sulfide reduction--oxidation processes u~u~leci. Amongst those analysed here, the waters showing 5180 ~ 0 may be considered closed systems, and, accordingly, an eventual oxygen isotopic positive correlation with the dissolved sulfates and the environmental waters would have proved the lack of a mixing with recent infiltration waters.
Experimental procedures The procedure used for the preparation of samples for measuring the 180(SO~-) was the same as that previously reported (Cortecci and Longinelli, 1968). The oxygen isotopic analyses of the resulting BaSO4 samples were carried out using the graphite-reduction technique as described in previous papers (Longinelli and Craig, 1967; Longinelli and Cortecci, 1970a). The sulfur-isotopic analyses were carried out using the technique as described by Ricke {1964). The oxygen and hydrogen isotopic data of all water samples reported here have already been published by Dowgiallo (1973). The isotopic ratios are given in the customary 5 notation, ~ being defined by the equation: 6 = (Rsample/Rstandard - - 1 ) • 1 0 3, in % , where R is the O18/O16 or S~/S 3~ isotopic ratios. The oxygen and hydrogen isotopic results are reported relative to the Standard Mean Ocean Water (SMOW) as defined by Craig (1961a). The standard deviation of the ~ ~80(SO~-) measurement is + 0.1% 0. The 8 ~S(SO~-) values are given relative to meteoritic sulfur standard {Canyon Diablo troilite) (Thode et al., 1961; Ault and Jensen, 1962; Jensen and Nakai, 1962). R E S U L T S AND DISCUSSION
The results obtained and reported in the Tables I, II, III and IV concern samples from different areas of the Poland: Carpathians, Carpathian foredeep, northwest Poland and Sudety Mountains localities (Fig.l).
Carpathian samples Only the 180/160 ratios of the sulfate dissolved in these waters have been measured. The results and other details are reported in Table I. DowgiaUo (1973) reports that these waters may be separated in three groups. To the first belong waters with 8180 not higher than --10°~0 and 8 D not higher than --70%. The low content in heavy isotopes suggests they are infiltration waters recharged from relatively high areas. To the second group belong waters with ~ 180 values from --9 to --2% and ~ D values from --60 to --30%. The presence of an admixture of marine relict water may be assumed here. The waters with 5 '80 ~ 0 have been reported as the result of an isotopic exchange with wall rock oras allochthonic relict waters of evaporating basins., other than the flysch ones. On this suggestion we return critically later The waters show mineralization values lower than that of modern mean sea
273
GDANSK
kLIN S wi n o ujscie..c~-""~K o ~ob r z e9 ~mien
OL.oSZTYN
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o
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.+Z ~e
AN
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o LUBLIN
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KIELCE O
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\
Busko
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/
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KRAKOWJ~
"~"
,,.,oo
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. <_:
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..Mu..,o.,
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.~,, ,~-. t~r .% Fig.1. T h e m a p shows the Poland localities f r o m which the samples ~ave been collected.
water (about 35 g/l), low sulfate concentration and 8 '80(SO~-) values ranging from +12°/00 to +17°&, with a mean value of +14.8%0 relative to SMOW. For the samples with 5180(H20) < 0 there is no correlation of ~ 180(SO~-) values with the isotopic composition of water, the chemical parameters, the outflow temperature, the age and the depth of the aquifers. The samples with 8 lSO(H20) > 0, outflowing from Upper Cretaceous and Tertiary flysch aquifers, show relatively high mineralization values. There is a positive correlation between the 5180(H20) > 0 and the 8 xso(so24 -) of dissolved sulfate (Fig.2). This correlation, with a slope of 0.3, is clearly due to an oxygen isotopic exchange and proves that these waters have not been mixed with recent infiltration waters, which would have shown no such correlation. F~om this point of view is significant that water samples from the same locality, i.e. Szczawnica and Wysowa, show markedly different ~ ~SO(H:O) values. In the case of the Szczawnica sulfate samples, the less positive 8180 = +11.8°/00 may reflect an isotopic exchange with a more negative water
Zakopane Zakopane Rabka Rabka Rabka Rabka Rabka Szczawnica Szczawnica Zegiestow Zegiestow Muszyna Muszyna Krynica Krynica Krynica Krynica Wysowa Wysowa Rymanov
Locality
IG1 IG1 Warzelnia Helena Boleslaw 18 19 Dzikie Magdalena Andrzej Anna Milusia Grunwald Slotwinka Mieczyslow Zuber I Zuber III Bronislawa II Aleksandra Odw. 1
Well name or No.
1,560 1,560 46 460 102 120 95 0.3 3.45 280 1.2 111 1.5 2 65 810 936 18 100 470
Triassic Triassic Tertiary Tertiary Tertiary Tertiary Tertiary U. Cretaceous U. Cretaceous Tertiary Tertiary Tertiary Tertiary Tertiary Tertiary Tertiary Tertiary U. Cretaceous U. Cretaceous Tertiary
36.0 36.0 10.5 12.2 10.1 10.5 13.5 10.8 10.8 9.9 8.8 9.0 9.3 7.9 9.1 11.1 10.3 9.2 12.1 16.1
temp. (°C)
depth (m)
age
Water's
Aquifer's
328 328 16,713 20,623 17,629 12,138 18,011 6,664 25,034 2,642 2,182 3,888 3.430 4,039 4,752 24,655 27,985 3,941 24,500 22,575
total salinity (ppm) 50 50 38 29 15 36 60 67 40 28 39 26 37 27 31 57 67 30 34 40
[SO~- ] (ppm)
---61.7 --55.8 --64.3 --27.6 --33.8
--70.1 --70.1 --30.9 --20.5 --33.0 --20.8 --31.8 --62.3 --35.6 --77.1 --74.7 --76.3 --71.8 --78.1
~ D(H~O
--10.6 --11.1 +2.8 +5.7 +2.3 +6.3 +3.1 --7.4 +3.8 --11.1 --10.9 --10.7 --10.6 --11.2 --11.1 --7.4 --7.5 --8.4 +6.6 +2.2
5 ~80(H20)
+16.1 +16.9 +15.2
+15.0 +14.7 +15.1 +15.5 +15.1 +15.8 +15.3 +11.8 +15.4 +13.2 +12.3 +15.5 +15.0 +15.2 +13.9 +15.2
6 ~sO(SO~-)
(1973).
* The ~ ~sO and 6 D values of the waters reported in this and in the other tables are taken from Dowgiallo and Tongiorgi (1972) and Dowgiallo
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
4 5
1 2 3
Sample No.
Isotopic composition of water and dissolved sulfate samples from the Carpathians*
TABLE I d~
275
17
Q
o o
16
o
O +x++*
o
o
~" %"
15
O~ 0
14
0
13
OiI
oo
•
•
o
0 12
o
1 I L JO J I L L J I I I L I I L I L L I L - 1 2 - 1 1 -1 - 9 - 8 - 7 - 6 - 5 - 4 - 3 - 2 -1 0 0 + 1 +2 +3 +4 +5 +6 +7
~'ao(Hzo )
Fig.2. Relationship among the 8 mO(SO~-) and 5 '80(H20) values. White circles, Carpathian samples; black circles, Carpathian foredeep samples; white squares, northwest Poland samples; black squares, Sudety Mountains samples.
or a mixing o f t w o isotopically different sulfates at least. The isotopicaUy more negative of this sulfate admixture may derive from the oxidation of sulfide compounds, resulting an impoverishment both in 180 and US isotopes. The ~ mO(SO~-) values are higher than that o f the present-day sea-water sulfate (+9.5°o) (Longinelli and Craig, 1967; Molcard et al., 1973). Assuming that the oxygen isotopic composition of the sea-water sulfate has varied little with geological time, and this assumption seems true up to and including the Tertiary (Sakai, 1972; Solomon et al., 1972), the 'sO contents of the analysed sulfate ions may reflect some isotopic enrichment processes, like the bacterial sulfate metabolism (Lloyd, 1967, 1968; Mizutani and Rafter, 1969) and the precipitation of the sulfate ions from the solution as gypsum or anhydrite (Lloyd, 1968). These processes enrich the residual sulfate and the solid phase both in 180 and in uS and may occur at the same time in an evapoxitic basin. It has to be underlined, however, that evaporatic conditions are not characteristic for the flysch basin, except some local phenomena reported by Ksiazkiewicz (1962).
Carpathian foredeep samples The samples c o m e from an area of marine Miocene sediments. The isotopic results and other details are shown in the Table II. As reported b y Dowgiallo (1973), the mineral waters occurring there may contain a lower (Busco, Solec samples) or higher (Debowiec sample) a m o u n t of relict marine water. The Dobowiec sample, which shows an isotopic composition very close to that of present-day sea-water, may be assumed as a relict Miocene sea-water. Its Na-C1, -Br and -I chemical contents and its total salinity agree with a marine origin, b u t the sulfate concentration is much lower than that of the present-day sea (about 2,700 ppm). Evaporitic conditions with CaSO4 precipitation, diagenetic bacterial reduction of sulfate ions and
Locality
Debowiec Busko Solec Solec
Sample No.
1 2 3 4
2 15 Szyb 2
Well name or No.
500 500 120 155
Miocene Maim U. Cretaceous U. Cretaceous
12.0 14.0
temp. (°C)
depth (m)
age
Water's
Aquifer's
31,869 22,861 21,074
total salinity (ppm)
10 920 3,080
[SO~- ] (ppm)
--3.6 --47.9 --39.3 --31.5
D(H20)
Isotopic composition of sulfate--water pairs from marine Miocene sediments (Carpathian foredeep)
TABLE II
0.0 --6.6 --5.7 --2.4
51'O(H20)
+14.7 +15.3 +12.9 +16.8
'~o(so]-)
+33.4 +29.7 +34.0
~3, S
O~
t~
277 dilution by infiltration water may account for the observed low SO~- content. So, the 81sO and 5 D values of the water included in the sediments probably in the Miocene time, should be higher than those meAsl]r~.d, due to ancient evaporitic conclitions. A mixing with more negative infiltration water may explain the observed isotopic values. The 'SO contents of the dissolved sulfates are close to those observed for the Carpathian water sulfates. The US contents are higher than that of presentday sea-water sulfate (6 uS = +20.0o/00) and very far from the 8 US values estimated for the ancient ocean sulfates (Thode and Monster, 1965; Holzen and Kaplan, 1966}. As shown in Fig.3, there is a positive correlation amongst the 180 and 34S contents of the analysed sulfates' and it, together with the high 5180 and 5 uS values, proves a bacterial elaboration of the dissolved sulfates. The Solec samples contain H2S and show different isotopic values both of the water and of the sulfate: to more negative ~ 180(H20) correspond more negative 61sO and 5 '8S of the dissolved sulfate. It may be due to an admixture of more positive sulfate with a 8180 value close to +17%0 with a more negative sulfate formed by H2S oxidation into a surface and oxygenated water.
18 17 Q
16
,,o
15
Q O10 11 Q9
3 Q2
14 '~3
,~ 2'0 ;5 36 3'~ ,6 ~'s(s0~') Fig.3. 5 ~ S(SO~- ) relative to ~ ~80(SO~- ). Black circles,Carpathian foredeep samples; white squares, northwest Poland samples.
Northwest Poland samples As reported by Dowgiallo and Tongiorgi (1972) these brines from the Mesozoic in northwest Poland may derive from highly saline fossil waters by dilution with recent meteoric waters. The ti 180 and 8 US values (see Table III) are higher than those of m o d e m sea-water sulfate and show a positive correlation (Fig.3) due, also in this case, to a sulfate reductive bacterial activity. No correlations occur with the isotopic quantity of the dissolved sulfate and the other parameters. Only the sample coming from Miedzywodzie Triassic aquifer shows a ~ US lower than that of
Locality
Swinoujscie Miedzywodzie Kam. Pomorski Kolobrzeg Kolobrzeg Kolobrzeg Ciechocinek Ciechocinek Cieehocinek Ciechocinek Ciechoeinek
Sample No.
1 2 3 4 5 6 7 8 9 10 11
5 IG1 Odw. 18 7 B1 8b 11 14 16 18
Well name or No.
185--260 1,015 415 2 41 102 34 414 757 1,364 1,450 Triassic Liassic Quaternary Dogger Dogger Maim Dogger Liassic Liassic Liassic
L. Cretaceous
27.5 32 32
19 10 10 10.5 11
temp. (°C)
depth (m)
age
Water's
Aquifer's
96,426 36,317 45,000 43,522 53,974 3,811 38,881 42,925 63,057 71,794
total salinity (ppm)
Isotopic composition of sulfate--water systems from the Mesozoic in northwest Poland
TABLE III
[ SO~- ]
244 360 44 920 76 496 604
2,560 244
(ppm)
--40.0 --39.0 --38.5
--44.0 --61.0
--56.0
D(H,O)
--7.4 --7.0 --7.2 --5.4 --8.0 --5.0 --4.7 --4.8 --4.6
6 I$O(H20)
+13.6 +13.6 +15.8 +16.5 +16.1 +16.4 +15.1 +16.3 +14.8 +15.4 +15.4
~180(SO~-)
+34.4 +29.0 +27.7 +25.6
+14.9 +31.8 +38.2 +32.2 +32.2
~]4S
Q0
t~
279
the present-day sea-water sulfate. The 6 uS value agrees with the probable value of the Upper Triassic sea-water sulfate (+13.1°/00) (Thode and Monster, 1965; Holzen and Kaplan, 1966; Nielsen, 1966). Assuming for this sample a low enrichment both in 180 and uS by means of bacteria, the 51so value of the Upper Triassic sea-water sulfate should be close to the m o d e m one. Sudety Mountains samples
The low content of heavy isotopes in the Sudetic waters (Table IV) shows f,heir infiltration origin (Dowgiailo, 1973). The waters from Carboniferous granitic aouifer show the lowest 5~80 (SO~-) values and the lowest salt contents. Positive ~ lSO(H20) values o f some Carpathian waters and their implications
As shown in Table I, several waters from Tertiary flysch aquifers show 5~so > 0. In the Fig.4 are shown the ~ 'sO-~ D correlations of the waters with 5180 ~< 0 and with 51so > 0. The 5~so ~< 0 values range from -11.0 to 0.0% 0, with a 5D range from - 7 7 to -3.6%0. All the points with 6~so ~< 0 are close to a straight line with a slope of 6.1, which agrees well with evaporation and wallrock isotopic exchange processes. As regards the samples with ~ 1so > 0, the ~ D-~ lSO straight line intercepts the ~ D--~ 1So line of meteoric waters found by craig (1961b) at ~ 1So = --9% and 5 D = --650/oo. The slope of 2.5 of this line excludes the evaporation process for the observed 180 enrichment. The slope becomes 3.1 if one assumes for the meteoric water in t h e Carpathian area the lowest isotopic values measured for the Carpathian water samples (6180 --11% and 5 D = --770/0o). This last slope agrees perfectly with that found by Coplen and Hanshaw (1973) in their water and solution ultrafiltration by compacted clay membrane experiments. An admixture of an isotopicaily very positive water with meteoric waters seems to be excluded by the very high ~ 1so value of this positive water =
0 •O10
o
"~
~
~
•
o
30
50 60 70 80 i
i
i
i
1
I
1
I
i
i
i
i
I
i
i
I
i
I
I
I
-12-11-10 - 9 -8 -7 - 6 - 5 - 4 -3 -2 -1 0.0+1 +2 +3 +4 +5 +6 +7
~ leO(H=O)
Fig.4. Water 5 D--81sO relationships. F o r the s y m b o l s see Fig.2. The straight line with slope 8 represents the meteoric waters (Craig, 1961b); for the other lines see text.
Locality
Cieplice Cieplice Cieplice Cieplice Cieplice Polanica Polanica
Sample No.
1 2 3 4 5 6 7
Marysienka Sobieski Nowe Waclaw Basenowe Damskie Wilka Pilniawa P300
Well name or No.
25 4.9 60 4.5 2 34 123 Carboniferous Carboniferous Carboniferous Carboniferous Carboniferous U. Cretaceous U. Cretaceous 23.7 22.6 37.6 18.1 43.8 11.5 4.5
(°c)
temp.
depth (m)
age
Water's
Aquifer's
Isotopic composition of sulfate--water pairs from Sudety Mountains
TABLE IV
661 513 651 689 668 1,605 2,692
total salinity (ppm)
[so~-]
166 73 160 154 179 34 63
(ppm)
--68.8 --67.6 --69.1 --65.5 --70.7
,~D(H20)
--10.5 --9.9 --10.4 --10.0 --10.6 --9.8
6~80(H20)
+13.0 +13.2 +11.6 +11.3 +11.7 +14.9 +14.4
6 "o(so,~-)
tO O0
281
(5 'so > 6.6°~0}: Longinelli and Nuti (1968) measuring the oxygen isotopic composition of phosphate from well-preserved fossil marine organism, propose for the Tertiary Mediterranean and for littoral areas of larger basin waters '80 values of +2.0 to +3.0°o relative to the mean m o d e m ocean water with a 5 '80 close to zero. Furthermore, their origin from meteoric infiltration waters submitted to a strong oxygen isotopic exchange with wall rocks is excluded by the relatively high 5 D values. Thus, the '80 contents of these waters and their 5 D---5180 slope are probably due to an isotopic fractionation by ultrafiltration through compacted clayey sediments: this process enriches the water of the residual solution in '80 and D isotopes. CONCLUSIONS
The analysed brines, thermal and cold mineral waters come from various old aquifers of different areas of Poland. Some of these waters are an admixture of relict sea water with infiltration meteoric water. The oxygen and the sulfur isotopic compositions of the analysed sulfate are higher than the m o d e m sea-water sulfate. These high isotopic contents and the positive 8180--~ US correlation may reflect a strong bacterial sulfate reductive activity in the water and in the bottom sediments of lagoons before and during the diagenesis. The dissolved sulfate may be syngenetic with the environmental water in the case of waters showing high or relatively high SO~- concentrations and positive or slightly negative 5 'sO values. For low SO~- concentrations and low 8180 and ~ D values of the waters, the dissolved sulfates may derive from leaching of sulfatic material disseminated in the rocks by infiltration waters. As regards the waters with 5 '80 > 0, the slope of the 8 '80--5 D relationship agrees very well with that found in ultrafiltration experiments using compacted clay as a membrane, and these waters can be explained as the residual ones in ultrafiltration processes through clays and shales. ACKNOWLEDGEMENTS
Thanks are due to E. Tongiorgi for helpful discussions. We are grateful to H. Nielsen who analysed the sulfates for uS at the Geochemischen Institut der Universit~it, GSttingen.
REFERENCES Ault, W.U. and Jensen, M.L., 1962. Summary of sulfur isotopic standards. In: M.L. Jensen (Editor), Biogeochemistry of Sulfur Isotopes, pp.16--19 Coplen, T.B. and Hanshaw, B.B., 1973. Ultrafiltration b y a compacted clay membrane. I. Oxygen and hydrogen isotopic fractionation. Geochim. Cosmochim. Acta, 37 : 2295-2310
282
Cortecci, G., 1973a. Oxygen-isotope variations in sulfate ions in the water of some Italian lakes. Geochim. Cosmochim. Acta, 3 7 : 1 5 3 1 - - 1 5 4 2 Cortecci, G., 1973b. Analisi isotopica di una formazione evaporitica del Miocene Superiore. Rend. Soc. Ital. Mineral. Petrol., 2 9 : 1 - - 1 8 Cortecci, G. and Longinelli, A., 1968". Oxygen-isotope measurements of sulfate ions separated from diluted solutions. Earth Planet. Sci. Lett., 4 : 3 2 5 - - 3 2 7 Cortecci, G. and Longinelli, A., 1970. Isotopic composition of sulfate in rainwater, Pisa, Italy. Earth Planet. Sci. Lett., 8 : 3 6 - - 4 0 Craig, H., 1961a. Standard for reporting concentrations of deuterium and oxygen-18 in natural waters. Science, 1 3 3 : 1 8 3 3 - - 1 8 3 4 Craig, H., 1961b. Isotopic variations in meteoric waters, Science, 1 3 3 : 1 7 0 2 - - 1 7 0 3 DowgiaUo, J., 1973. Wyniki badin skladu isotopowego tlenu i wodorn wodach podziemnych Polski poludniowej (Results of measurements o f the oxygen and hydrogen isotopic composition of groundwaters of South Poland). Inst. Geol. Buil., 2 7 7 : 3 1 9 - - 3 3 8 Dowgiallo, J. and Tongiorgi, E., 1972. Isotopic composition of oxygen and hydrogen in some brines from the Mesozoic in northwest Poland. Geothermics, 1 : 67--69 Holzen, W.T. and Kaplan, I.R., 1966. Isotope geochemistry of sedimentary sulfates. Chem. Geol., 1 : 9 3 - - 1 3 5 Jensen, M.L. and Nakai, N., 1962. Sulfur isotope meteorite standards results and recommendation. In: M.L. Jensen (Editor), Biogeochemistry of Sulfur Isotopes, pp.30--35 Ksiazkiewicz, M., 1962. On the occurrence of gypsum in the Magura flysch. Bull. Acad. PoL Sci., Set. Sci. Geol. Geogr. (Varsovic), 10(1) Lloyd, R.M., 1967. Oxygen-18 composition of oceanic sulfate. Science, 1 5 6 : 1 2 2 8 - - 1 2 3 1 Lloyd, R.M., 1968. Oxygen isotope behavior in the sulfate-water system. J. Geophys. Res., 7 3 : 6 0 9 9 - - 6 1 1 0 Longinelli, A. and Cortecci, G., 1970a. ComPosizione isotopica dell'ossigeno nei solfati. Tecniche di misura. Rend. Soc. Ital. Mineral. Petrol., 2 6 : 7 3 3 - - 7 4 3 Longinelli, A. and Cortecci, G., 1970b. Isotope abundance of oxygen and sulfur in sulfate ions from river water. Earth Planet. Sci. Lett., 7 : 3 7 6 - - 3 8 0 Longinelli, A. and Craig, H., 1967. Oxygen-18 variations in sulfate ions in sea water and saline lakes. Science, 1 5 6 : 5 6 - - 5 9 Longinelli, A. and Nuti, S., 1968. Oxygen-isotope ratios in phosphate from fossil marine organisms. Science, 1 6 0 : 8 7 9 - - 8 8 2 Mizutani, Y. and Rafter, T.A., 1969. Bacterial fractionation of oxygen P-~d sulfur isotopes in the reduction o f sulfate and in the oxidation of sulfur. N. Z. J. Sci., 1 2 : 6 0 - - 6 8 Molcard, R., Cortecci, G. and Noto, P., 1973. Isotopic analysis of the deep staircase structure in the Tyrrhenian Sea. Unclassified SACLANTCEN Memorandum SM-24 Nielsen, H., 1966. Schwefelisotope in marinem Kreislauf und das ~ 34S der friiheren Meere. Geol. Rundsch., 5 5 : 1 6 0 - - 1 7 2 Ricke, W., 1964. Preparation von Schwefeldioxid zur massenspektrometrischen Bestimmung des Schwefel-Isotopen-Verhiiltnisses ~ S/~S in natiirlichen Schwefelverbindungen Z. Anal. Chem., 1 9 9 : 4 0 1 - - 4 1 3 Sakai, H., 1972. Oxygen isotopic ratios of some evaporites from Precambrian to Recent ages. Earth. Planet. Sci. Lett., 1 5 : 2 0 1 - - 2 0 5 Schwarcz, H.P. and Cortecci, G., 1974. Isotopic analyses of spring and stream water sulfate from the Italian/kips and Apennines. Chem. Geol. 1 3 : 2 8 5 - - 2 9 4 Solomon, M., Rafter, T.A. and Dunham, K.G., 1971. Sulfur and oxygen isotope studies in the northern Pennines in relation to ore genesis. Appl. Earth. Sci., 8 0 : 3 2 5 9 - - 3 2 7 5 Thode, H.G. and Monster, J., 1965. Sulfur-isotopic geochemistry of petroleum, evaporites and ancient seas. Reprinted from: Fluids in Subsurface Environments. A Symposium. Am. Assoc. Petrol. Geol., Mem., 4 : 3 6 7 - - 3 7 7 Thode, H.G., Monster, J. and Dunford, H.G., 1961. Sulfur isotope geochemistry. Geochim. Cosmochim. Acta, 2 5 : 1 5 9 - - 1 7 4