Focused fluid flow during subduction: Oxygen isotope data from high-pressure ophiolites of the western Alps

Barnicoat, A. C.; Cartwright, Ian

doi:10.1016/0012-821x(95)00040-j

Cited by 75 publications

(59 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Oxygen isotope studies of relatively undeformed high-P metamorphic rocks suggest that the isotope values of seafloor alteration may be preserved during metamorphism (e.g., Barnicoat and Cartwright 1995;Putlitz et al 2000;Früh-Green et al 2001). In this case, the heavy d…”

Section: Discussionmentioning

confidence: 99%

“…In these zones, the fluid may interact with mafic and pelitic rocks to produce melts or trace element-rich fluids that then ascend into the mantle wedge to contribute to arc magma-genesis . Field and isotopic evidence from PEM and other high-P terranes (e.g., Barnicoat and Cartwright 1995;Scambelluri and Philippot 2001;Ague 2006) suggest that large-scale fluid flow in subduction zones is highly channellized. The interaction between fluids derived from lower-slab serpentinite and upper-slab mafic and pelitic rocks may therefore be somewhat limited.…”

Section: Formation Of Hybrid Rocks In Subduction Mélangesmentioning

confidence: 99%

See 1 more Smart Citation

The importance of talc and chlorite “hybrid” rocks for volatile recycling through subduction zones; evidence from the high-pressure subduction mélange of New Caledonia

Spandler

Hermann

Faure

et al. 2007

Contrib Mineral Petrol

154

111

View full text Add to dashboard Cite

The transfer of fluid and trace elements from the slab to the mantle wedge cannot be adequately explained by simple models of slab devolatilization. The eclogite-facies mélange belt of northern New Caledonia represents previously subducted oceanic crust and contains a significant proportion of talc and chlorite schists associated with serpentinite. These rocks host large quantities of H 2 O and CO 2 and may transport volatiles to deep levels in subduction zones. The bulk-rock and stable isotope compositions of talc and chlorite schist and serpentinite indicate that the serpentinite was formed by seawater alteration of oceanic lithosphere prior to subduction, whereas the talc and chlorite schists were formed by fluid-induced metasomatism of a mélange of mafic, ultramafic and metasedimentary rocks during subduction. In subduction zones,

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Formation Of Hybrid Rocks In Subduction Mélangesmentioning

confidence: 99%

The importance of talc and chlorite “hybrid” rocks for volatile recycling through subduction zones; evidence from the high-pressure subduction mélange of New Caledonia

Spandler

Hermann

Faure

et al. 2007

Contrib Mineral Petrol

154

111

View full text Add to dashboard Cite

show abstract

“…Barnicoat and Cartwright, 1995;Bebout, 2007;Zheng et al, 2003 (Fig. 5), indicating O isotopic equilibration based on the approximate limits of equilibrium fractionation between omphacite and garnet at eclogite-facies conditions (Zheng et al, 2003).…”

Section: Morb-type Eclogites: Evidence For Seafloor Alterationmentioning

confidence: 99%

“…Oxygen isotope signatures of ocean-floor basalts are generally preserved through subduction-zone metamorphism, although δ 18 O can locally be modified (e.g., Barnicoat and Cartwright, 1995). Devolatilization of subducting rocks is not considered to produce appreciable shifts in the O isotope composition because the majority of the O reservoir is retained in the residue (Bebout, 2007), and prograde metamorphic effects are thought not to lower δ 18 O of a rock by more than 1-2 ‰ (Valley, 1986).…”

Section: Morb-type Eclogites: Evidence For Seafloor Alterationmentioning

confidence: 99%

“…Unlike oxygen, lithium has trace concentrations in most rocks and has therefore a differing sensitivity to fluid-rock interaction than the O isotope system, which is widely used to constrain the extent of fluid flow and to distinguish between external and internal fluid sources (e.g., Barnicoat and Cartwright, 1995;Bebout and Barton, 1993;Zheng et al, 2003).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A stable (Li, O) and radiogenic (Sr, Nd) isotope perspective on metasomatic processes in a subducting slab

et al. 2011

View full text Add to dashboard Cite

Two distinct types of eclogites from the Raspas Complex (Ecuador), which can be distinguished based on petrography and trace element geochemistry, were analyzed for their stable (Li, O) and radiogenic (Sr, Nd) isotope signature to constrain metasomatic changes due to fluid-overprinting in metabasaltic rocks at high-pressure conditions and to identify fluid sources. MORB-type eclogites are characterized by a relative LREE depletion similar to MORB. High-pressure (HP) minerals from this type of eclogite have highly variable oxygen isotope compositions (garnet: +4.1 to +9.

show abstract

Sulfur isotope evolution in sulfide ores from Western Alps: Assessing the influence of subduction-related metamorphism

Giacometti

Evans

Rebay

et al. 2014

Geochem. Geophys. Geosyst.

View full text Add to dashboard Cite

Sulfides entering subduction zones can play an important role in the release of sulfur and metals to the mantle wedge and contribute to the formation of volcanic arc-associated ores. Fractionation of stable sulfur isotopes recorded by sulfides during metamorphism can provide evidence of fluid-rock interactions during metamorphism and give insights on sulfur mobilization. A detailed microtextural and geochemical study was performed on mineralized samples from two ocean floor-related sulfide deposits (Servette and Beth-Ghinivert) in high-pressure units of the Italian Western Alps, which underwent different metamorphic evolutions. The combination of microtextural investigations with d 34 S values from in situ ion probe analyses within individual pyrite and chalcopyrite grains allowed evaluation of the effectiveness of metamorphism in modifying the isotopic record and mobilizing sulfur and metals and have insights on fluid circulation within the slab. Textures and isotopic compositions inherited from the protolith are recorded at Beth-Ghinivert, where limited metamorphic recrystallization is attributed to limited interaction with metamorphic fluids. Isotopic modification by metamorphic processes occurred only at the submillimeter scale at Servette, where local interactions with infiltrating hydrothermal fluid are recorded by metamorphic grains. Notwithstanding the differences recorded by the two deposits, neither underwent intensive isotopic reequilibration or records evidence of intense fluid-rock interaction and S mobilization during metamorphism. Therefore, subducted sulfide deposits dominated by pyrite and chalcopyrite are unlikely to release significant quantities of sulfur to the mantle wedge and to arc magmatism sources at metamorphic grades below the lower eclogite facies.

show abstract

Focused fluid flow during subduction: Oxygen isotope data from high-pressure ophiolites of the western Alps

Cited by 75 publications

References 22 publications

The importance of talc and chlorite “hybrid” rocks for volatile recycling through subduction zones; evidence from the high-pressure subduction mélange of New Caledonia

The importance of talc and chlorite “hybrid” rocks for volatile recycling through subduction zones; evidence from the high-pressure subduction mélange of New Caledonia

A stable (Li, O) and radiogenic (Sr, Nd) isotope perspective on metasomatic processes in a subducting slab

Sulfur isotope evolution in sulfide ores from Western Alps: Assessing the influence of subduction-related metamorphism

Contact Info

Product

Resources

About