On the formation of metal-rich deposits at ridge crests

Edmond, John M.; Measures, C.I.; Mangum, B.; Grant, B.; Sclater, F.R.; Collier, Robert W.; Hudson, Andrew; Gordon, Louis; Corliss, John B.

doi:10.1016/0012-821x(79)90062-1

Cited by 290 publications

(86 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Vein-related alteration is manifest as different-colored alteration halos along veins. Black halos contain celadonite and have been interpreted to result from the presence of upwelling distal low-temperature hydrothermal fluids enriched in iron, silica, and alkalis (Edmond et al, 1979; see summary in Alt and Teagle, 1999). The iron oxyhydroxide-rich brown mixed halos are later features that formed by circulation of oxidizing seawater.…”

Section: Headline Results From Previous Drilling At Site 1256: Odp Lementioning

confidence: 99%

Expedition 335 summary

Teagle¹,

Ildefonse²,

Blum³

et al. 2012

Proceedings of the IODP

View full text Add to dashboard Cite

Section: Headline Results From Previous Drilling At Site 1256: Odp Lementioning

confidence: 99%

Expedition 335 summary

Teagle¹,

Ildefonse²,

Blum³

et al. 2012

Proceedings of the IODP

View full text Add to dashboard Cite

“…Black halos contain celadonite and have been interpreted to result from the presence of upwelling distal low-temperature hydrothermal fluids enriched in iron, silica, and alkalis (Edmond et al, 1979;see summary in Alt, 1999). Iron oxyhydroxide-rich brown mixed halos are later features that formed by circulation of oxidizing seawater.…”

Section: Expedition 309/312 Scientists Site 1256mentioning

confidence: 99%

Site 1256

2006

Proceedings of the IODP

View full text Add to dashboard Cite

“…Subsequent discovery of high-temperature vents at mid-ocean ridges [e.g., Edmond et al, 1979), seamounts [MalaJwff et al, 1982], and back arc basins [Horbie et al, 1986] showed that hydrothermal circulation is a fundamental process in many oceanic environments.…”

Section: In1roouc110nmentioning

confidence: 99%

Patterns and processes of alteration in the lavas and dykes of the Troodos Ophiolite, Cyprus

Gillis¹,

Robinson²

1990

J. Geophys. Res.

112

View full text Add to dashboard Cite

Alteration panenu in the lavas and dykes of the Troodos Ophiolite, Cypnu, record a compte~ ~st~ of axial hydrochennal alteration, crustal aging, and.subsequent uplift ~d c;rnptac~ent of ~e ophiolite. ~1eld mappina shows that distribution of five alteration zooes, each ~ith duunct rruneralog•cal, gcochermcal, and hydroloaic characteristics, is influenced by igneous stratigraphy, st~cture~ a~d the nature a.nd thickness of the overlying aedimenu. Paragenetic aequences of ICCOlldary ~erals indicate .that alteration conditions changed proareasively as the crust cooled and moved o(f~Uls. Along spreading axes, low temperatures ~SO"C) were mainuined by the rapid flow of seawater m and out of the lavas, and .only minimal alteration took place. In contrast, lower water/rock ratios and hlgh~r te.mperarures (>200°C) m the dykes promoted extensive seawater·rock interaction. Althou~~ the sharp rue .m ~perarure between the two reJ.imes generally coincides with the lava-dyke transJUoo, late· stage mtrus1ons or hydrothermal upwellina zooes locally cause high·temperarure alteration to extend upward .into the lavas. As a segment of crust moved off·axis, temperatures remained tow in the lavas and proaress1vety decreased, ~rom. >250" 10 <80"C in the dykes. High permeability in the uppermost lavas led to the downward rruarauon of an oxidati~e alteration front whose thickness and spatial distribution was dependent upon the. rate and nature of sedimentation and, thus, the original seafloor morphology. Although field relations sho.w that alteration has a consistent vertical pattern in Troodos, the alteration zooes are not laterally oonunuous, and the stratigraphic depth of their boundaries varies considerably. IN1ROOUC110NEarly studies of the massive sulfide deposits [Constantinou and Govett, 1973) and alteration patterns within the Troodos ophiolite [Gass and Smewing, 1973) contributed greatly to the development of models for oceanic hydrothermal systems [SpooMr et al., 1977; C haprno.n and SpooMr, 1977] and subseafloor metamorphism [Coleman, 1977]. Subsequent discovery of high-temperature vents at mid-ocean ridges [e.g., Edmond et al., 1979), seamounts [MalaJwff et al., 1982], and back arc basins [Horbie et al., 1986] showed that hydrothermal circulation is a fundamental process in many oceanic environments.Mineralogical and chemical zonations within the Troodos massive sulfide ore deposits indicate that they formed from hydrothermal flu1ds whose compositions were remarkably similar to those venting on the seafloor today [Adamides, 1987;Herzig and Friedrich , 1987;Richards et al., 1989). Fluid compositions in Troodos were buffered by epidosites at conditions similar to those inferred for the root-zones of active systems at mid-ocean ridges [Bowers and Taylor, 1985;Richardson et al., 1987;Schiffman et al., 1987;Schiffman and Smith, 1988;Seyfried et al., 1988;Von Damm, 1988] . Because of these and other similarities, the upflow zones of the Troodos hydrothermal systems are thought to be ancient analogues of modem active systems [Oud...

show abstract

On the formation of metal-rich deposits at ridge crests

Cited by 290 publications

References 36 publications

Expedition 335 summary

Expedition 335 summary

Site 1256

Patterns and processes of alteration in the lavas and dykes of the Troodos Ophiolite, Cyprus

Contact Info

Product

Resources

About