Sulfur isotopes in the Rammelsberg ore deposit (Germany)

Anger, Gerd; Nielson, Heimo; Puchelt, Harold; Ricke, Werner

doi:10.2113/gsecongeo.61.3.511

Cited by 63 publications

(26 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The ion microprobe results from the Rammelsberg sample are entirely consistent with the larger conventional study of Anger et al (1966) and we would suggest that some of the points covered in Eldridge et al (1988a) can be argued from either data base (Fig. 1).…”

supporting

confidence: 85%

Sulfur isotope variability in sediment-hosted massive sulfide deposits as determined using the ion microprobe SHRIMP; I, An example from the Rammelsberg orebody; reply

Eldridge¹,

Walshe²,

Compston³

et al. 1989

Economic Geology

View full text Add to dashboard Cite

Sir: We wish to thank Goodfellow and Turner for the opportunity to discuss further several points made in our paper (Eldridge et al., 1988a). First, it is imperative that we remove any illusions concerning the discussion of the Rammelsberg orebody from the data gathered in our study of a single sample. We do not view ourselves as pioneers in reporting key features located in a single sample and wish to point out that this study is no special case in the course of geologic investigations. It is not unheard of in the geologic world for one sample to contain the pertinent features of a larger body since, among other examples, it is possible to obtain a sample from a single vein holding four major alteration assemblages associated with significant expanses of porphyry copper mineralization (i.e., Meyer and Hemley, 1967); single samples may be found that contain all types of fluid inclusions from a given porphyry copper orebody (i.e., Bodnar and Beane, 1980); single thin sections of chemically zoned metamorphic minerals may yield critical information for large terrains (e.g., Selverstone et al., 1984); individual samples have been identified which contain a record of all significant thermal events experienced by massive bodies of rock (Black et al., 1986); or a single cube of galena may hold as much information as a whole Mississippi Valley-type deposit and nearly that of the entire Mississippi Valley district (Hart et al., 1981). Similar to these examples, and the Rammelsberg paper in particular, other sizable mineralizing systems have been found, in the course of our studies with the ion microprobe, in which single samples contained as much information as conventional investigations involving greater spatial coverage. Furthermore, several ion microprobe studies, which have actually involved acquisition of more data from an orebody than any previous conventional studies, have brought to light single samples which prove to hold more information than that of the entire conventional study (Eldridge et al., 1988b; McKibben and Eldridge, 1989). While we do not advocate selection of random single samples to use as sole representations of larger areas, we do feel that in this case, as in many others from the geologic community, a sample has been found which is consistent with a much larger body of data concerning a geologic entity. The ion microprobe results from the Rammelsberg sample are entirely consistent with the larger conventional study of Anger et al. (1966) and we would suggest that some of the points covered in Eldridge et al. (1988a) can be argued from either data base (Fig. 1). However, we feel that a major contribution has been made in our paper in that the microanalytical study has augmented the conventional investigation through retention of the continuity in ore textures associated with the isotope results. Finally, it should be recognized that this information has always been available in the small sample; it has only been arduous to uncover due to traditional sampling methods.Second, concerning the source ...

show abstract

supporting

confidence: 85%

Sulfur isotope variability in sediment-hosted massive sulfide deposits as determined using the ion microprobe SHRIMP; I, An example from the Rammelsberg orebody; reply

Eldridge¹,

Walshe²,

Compston³

et al. 1989

Economic Geology

View full text Add to dashboard Cite

show abstract

“…This suggests that some pyrites and chalcopyrites of the Iwami sulfide ores were con taminated by biogenic sulfur present in the depositional and/or postdepositional environments, although the reason why of sulfide minerals pyrite and chalcopyrite were contaminated preferentially by biogenic sulfur cannot be known by the present author. A similar idea has been proposed by ANGER et al (1966) If the idea above mentioned is accepted, isotope data would indicate that chalco pyrite and especially pyrite of the bedded ores were more pronouncedly affected by beiogenic sulfur than those of the disseminated ores. MOTEGI (1968) has suggested that bedded ores were formed by re-deposition of fine-grained ore fragments and clay in the shallow sea floor, while disseminated ores were formed by re-deposition of rather coarse-grained ore fragments in the deeper horizon .…”

Section: Resultssupporting

confidence: 61%

Distribution of sulfur isotopes in the Iwami Kuroko deposits, Shimane Prefecture, Japan

Yamamoto

1974

Geochem. J.

View full text Add to dashboard Cite

Abstract-Sulfur isotope study of the Iwami Kuroko deposits shows that sulfide minerals from the disseminated ores, the bedded ores, the mudstones and the gypsum ores have 8345 values ranging from +1.2 to +5.5%o, from -0.8 to +5.4'/00, from -7.7 to -1.20/00, and from -15.3 to +5.4%o, respectively. Pyrites from the bedded ores exhibit a wider spread in the 8345 value (-0.8 to +5.4%o) than pyrites from the disseminated ores (+3.1 to +5.5%0), and chalcopyrites of the bedded ores have 8345 values ranging from +0.9 to +2.2%o, which are lower than those for chalcopyrites of the disseminated ores (+2.1 to +4.6%o). 8345 values for barites from the bedded ores and the mudstones and gypsums from the gypsum ores are fairly uniform, ranging from +19.5 to +23.2 %o.Sulfur isotope temperatures calculated for sphalerite-galena pairs of the dissemi nated ores are fairly constant, giving the values of around 290°C, which are not so much different from 250°C obtained for most sulfide pairs from the Kuroko deposits in Northeast Japan (KAJIWARA and DATE, 1972). Other sulfide pairs including pyrite and/or chalcopyrite, however, give so much variable isotope temperatures.The observed isotopic distribution in the disseminated ores and the bedded ores may be explained by the assumption that pyrite and chalcopyrite were preferentially contaminated by biogenic sulfur during and/or after the ore deposition. Low and variable 534S values obtained for pyrites from the mudstones and the clay of the gypsum ores suggest that these pyrites are of biogenic origin.

show abstract

“…13 to 37 per mil and average 23 per mil (Anger et al, 1966). If we accept the interpretation of Anger et al that the barite sulfate is of seawater origin, then the fact that these isotopic values are considerably less than values predicted for a system closed to sulfate (i.e., >70%0) demonstrates further that the assumption of closed conditions is probably incorrect and that sulfate did exchange across the redox boundary.…”

Section: Values Of •Ia4s For Barite At Rammelsberg Range Frommentioning

confidence: 69%

“…We further suggest that the sulfur isotope data presented by Eldridge et al (1988) and Anger et al (1966) is more reasonably interpreted in the light of a model in which most of the Rammelsberg su!fides were derived from an ambient anoxic water column that is at least semiopen to both sulfide and sulfate. This model not only explains the magnitude and range of •ia4S values, and the consistency of isotopic ratios between host rocks and ores, but also the lack of isotopic differences between the "biogenic" and "hydrothermal" textural types described by Eldridge et al (1988). Comments and suggestions by J. W. Lydon, I. R. Jonasson, and E. M. Cameron for this discussion are greatly appreciated.…”

Section: Values Of •Ia4s For Barite At Rammelsberg Range Frommentioning

confidence: 77%

“…Goldhaber and Kaplan (1974), for example, have demonstrated that there is usually open exchange of sulfur between pore waters and the overlying water column in modern basins characterized by low sedimentation rates. At Rammelsberg, biogenic sulfides from the host Wissenbacher shales have about the same average (13%0) and range as ore sulfides (Anger et al, 1966), indicating that a model envisaging exchange of sulfide between sediment and water column is more realistic than two independent closed systems, and furthermore, is consistent with deriving sulfide sulfur from the ambient water column.…”

mentioning

confidence: 70%

See 1 more Smart Citation

Sulfur isotope variability in sediment-hosted massive sulfide deposits as determined using the ion microprobe SHRIMP; I, An example from the Rammelsberg orebody; discussion

Goodfellow¹,

Turner²

1989

Economic Geology

View full text Add to dashboard Cite

Sir: Eldridge et al. (1988) present important evidence obtained by SHRIMP ion probe sulfur isotope microanalysis of sulfides from a single clastic sample of the Rammelsberg deposit for retention of sulfur isotope compositions in sulfides subjected to greenschist metamorphism, for lack of isotopic equilibria between adjacent sulfide grains, and for homogeneity of isotopic compositions within individual sulfide grains. Using these results, the authors argue that sulfide sulfur in the Rammelsberg deposit must have been introduced with hydrothermal fluids by dismissing the other possible source, biogenic sulfide in a reduced, ambient water column. Notwithstanding the problem of extrapolating the results of one sample to the entire deposit, it is our opinion that arguments advanced by Eldridge and his coauthors do not in fact preclude a seawater source of isotopically heavy sulfide sulfur in the Rammelsberg deposit. Analyses of pyrite reported by Eldridge and coworkers fall into two groups: •34S = -13 to 0 per mil (3 samples) and •;34S = 12 to 14 per rail (4 samples). Three chalcopyrite grains range from 12 to 14 per mil; chalcopyrite mantles both isotopically lighter pyrite (•4S ---10%0) and isotopically similar pyrite (•4S = +12%0). Eldridge et al. (1988) interpret the isotopically light pyrite to have formed by biogenic sulfate reduction, and the isotopically heavier pyrite and chalcopyrite to have formed from sulfur of hydrothermal origin. No data for the economically important minerals sphalerite and galena are presented. The authors dismiss a seawater source of sulfide sulfur because the character and isotopic systematics of the Rammelsberg deposit is not predicted by their models of ore-forming environments. We question whether the models the authors have chosen are appropriate. Eldridge et al. (1988) consider two models for biogenic reduction in a water column: a basinal environment closed to both sulfide and sulfate, and an environment open to sulfide but closed to sulfate. Also assumed are sulfate/sulfide ratios are equivalent to the modern Black Sea, and that the ores formed from a single, nonreplenished volume of seawater. However, based on available evidence, we feel that (1) the Black Sea is a poor analogue for reduced Paleozoic basins, (2) the duration of ore formation precludes the assumption of a fixed seawater volume, and (3) the Rammelsberg depositional environment is more accurately modeled as open to sulfide and sulfate. First, the Black Sea is a poor analogue for ancient anoxic basins because the percentage of sulfate (•2% of dissolved SO• 2) bacterially reduced to sulfide is very small. Goodfellow and Jonasson (1984), for example, have shown, using Rayleigh distillation equations (Nakai and Jensen, 1964) in conjunction with sulfur isotope values in pyrite from shales not associated with Pb-Zn deposits, that greater than 60 percent of the ambient seawater sulfate was reduced to sulfide during several periods in the history of the Paleozoic Selwyn basin. The Wissenbacher shales, host to the Rammel...

show abstract

Sulfur isotopes in the Rammelsberg ore deposit (Germany)

Cited by 63 publications

References 0 publications

Sulfur isotope variability in sediment-hosted massive sulfide deposits as determined using the ion microprobe SHRIMP; I, An example from the Rammelsberg orebody; reply

Sulfur isotope variability in sediment-hosted massive sulfide deposits as determined using the ion microprobe SHRIMP; I, An example from the Rammelsberg orebody; reply

Distribution of sulfur isotopes in the Iwami Kuroko deposits, Shimane Prefecture, Japan

Sulfur isotope variability in sediment-hosted massive sulfide deposits as determined using the ion microprobe SHRIMP; I, An example from the Rammelsberg orebody; discussion

Contact Info

Product

Resources

About