Near-solidus evolution of oceanic gabbros: insights from amphibole geochemistry

Coogan, L. A.; Wilson, Robert N.; Gillis, K. M.; MacLeod, C. J.

doi:10.1016/s0016-7037(01)00714-1

Cited by 136 publications

(117 citation statements)

References 38 publications

Supporting

Mentioning

102

Contrasting

Order By: Relevance

“…Therefore, a water-rich plagioclase-undersaturated melt, carrying fluid mobile elements, reacted with the cumulate/mush pile to produce late-stage interstitial amphibole. The reaction of clinopyroxene with a melt, to form amphibole has been observed in cumulates (Best 1975;Debari et al 1987;Coogan et al 2001;Smith 2014;Bouilhol et al 2015) and we believe this is a common process in Martinique plutonic xenoliths.…”

Section: VIsupporting

confidence: 60%

“…McBirney and Noyes 1979;Morse 1996), or in an open system involving the input of percolating reactive melts or liquids (Reiners 1998;Coogan et al 2000Coogan et al , 2001Meurer and Claeson 2002;Leuthold et al 2014;Smith 2014;Bouilhol et al 2015;Stuart et al 2016). It has been shown that the products of reactive liquid flow will differ from one produced by simple crystallisation along a liquid line of descent (Reiners 1998) and the addition of low degree melts cause large variations in incompatible trace elements.…”

Section: VImentioning

confidence: 99%

See 1 more Smart Citation

Plutonic xenoliths from Martinique, Lesser Antilles: evidence for open system processes and reactive melt flow in island arc crust

Cooper

Davidson

Blundy

2016

Contrib Mineral Petrol

View full text Add to dashboard Cite

Section: VIsupporting

confidence: 60%

Section: VImentioning

confidence: 99%

Plutonic xenoliths from Martinique, Lesser Antilles: evidence for open system processes and reactive melt flow in island arc crust

Cooper

Davidson

Blundy

2016

Contrib Mineral Petrol

View full text Add to dashboard Cite

“…However, the Wadi Gaz pargasitic amphiboles have also a high TiO 2 content, correlated with a high fluor content (Figures 12a and 12b). High values of these two elements are considered as the signature of magmatic amphiboles [MacLeod and Yaouancq, 2000;Coogan et al, 2001]. At this stage, we discern that the question of magmatic versus hydrothermal origin of pargasitic amphiboles cannot be settled by our data.…”

Section: Origin Of Watermentioning

confidence: 70%

Root zone of the sheeted dike complex in the Oman ophiolite

Nicolas

Boudier

Koepke

et al. 2008

Geochem Geophys Geosyst

View full text Add to dashboard Cite

[1] In the Oman ophiolite crustal section, a contact zone between the gabbro unit and the volcanics and diabase sheeted dikes, called the root zone of the sheeted dike complex, has been recently mapped at a fine scale in a selected area. The Oman ophiolite is derived from a fast spreading ridge which had a melt lens located between the main gabbro unit and the root zone of the sheeted dike complex. With a few exceptions accounted for, this horizon has a fairly constant thickness, $100 m, and a crude internal pseudo-stratigraphy. At the base of the root zone are isotropic ophitic gabbros interpreted as a thermal boundary layer. This layer is transitional between the magmatic system of the melt lens, convecting at 1200°C, and a high-temperature (<1100°C) hydrothermal system, convecting within the root zone. Above this level, the isotropic gabbros have been, locally, largely molten due to an influx of seawater, at $1100°C, thus generating varitextured ophitic and pegmatitic gabbros. These latter gabbros constitute the upper part of the root zone and are associated with trondjhemitic intrusions as screens in the lower sheeted dikes. Diorites and trondjhemites were also generated by hydrous melting, at temperatures below 1000°C. The whole root zone is a domain of very sharp average thermal gradient ($7°C/m). At the top of the root zone, a new thermal boundary layer, with diabase dikes hydrated in amphibolite facies conditions, separates the preceding high-temperature convective system from the well-known greenschist facies (<450°C) hydrothermal system operating throughout the sheeted dike complex, up to the seafloor. The isotropic gabbros near the base of the root zone are intruded by protodikes with distinctive microgranular margins and an ophitic center. Protodike swarms are exceptional because, intruding a medium at $1100°C, they are largely destroyed by dike-in-dike intrusions and by hydrous melting. However, they demonstrate that this zone was generated by melt conduits issued from the underlying melt lens. Each dike of the sheeted dike complex is thus fed by one protodike. As this zone has been recently drilled by IODP in the eastern Pacific Ocean, a brief comparison is proposed.

show abstract

“…Tribuzio et al, 1999a;Tiepolo and Tribuzio, 2005;Renna et al, 2006). Mineral-melt interaction during late stage crystallization has been identified in rocks of variable geochemical affinity, including tholeiitic (Gillis, 1996;Tribuzio et al, 1999bTribuzio et al, , 2000Coogan et al, 2001) and continental calc-alkaline magmas, the latter sometimes associated with post-collisional geodynamic settings (Monjoie et al, 2005;Tiepolo and Tribuzio, 2005;Renna et al, 2006). The nature of magmas formed during orogenic events is commonly unclear due to the involvement of several geochemical reservoirs (crust and mantle) and the leading role played by differentiation processes (e.g., fractional crystallisation and crustal contamination), which may obliterate the primary geochemical signature.…”

Section: Introductionmentioning

confidence: 99%

“…The determination of major and trace element mineral composition by microanalytical techniques (Electron Microprobe and Laser Ablation ICP-MS) in rock suites subjected to complex crystallization stories has proved as a main tool in deciphering the type of operating magmatic processes (e.g., Tribuzio et al, 1999b;Coogan et al, 2001;Claeson and Meurer, 2004;Bernstein, 2006;Borghini and Rampone, 2007). This approach allows the characterization of trace element mineral zoning and other micro-scale chemical heterogeneities.…”

Section: Introductionmentioning

confidence: 99%

Mineral chemistry of late Variscan gabbros from central Spain: constraints on crystallisation processes and nature of the parental magmas

García

Losantos

Villaseca

et al. 2015

Journal of Iberian Geology

View full text Add to dashboard Cite

Major and trace element chemistry has been determined in the main minerals (olivine, orthopyroxene, clinopyroxene, plagioclase, amphibole, phlogopite) from the Talavera and La Solanilla gabbroic intrusions (Spanish Central System). The results show a heterogeneous mineral composition illustrative of the chemical evolution of calc-alkaline basic magmas during crystallization. The formation of incompatible element-rich interstitial minerals, such as amphibole, phlogopite and accessory phases (e.g., zircon, apatite), and the presence of zoning patterns in major minerals towards a more evolved composition, point to a progressive differentiation of the parental melt. The chemical variation depicted by trace elements usually incompatible with clinopyroxene (e.g., rare earth elements (REE), Th, Zr, Nb, Ti) implies co-precipitation with phases displaying a compatible behaviour with respect to these elements (e.g., apatite, zircon, amphibole). However, the very high LILE (large ion lithophile elements) and LREE (light REE) shown by clinopyroxene can not be explained exclusively by a closed-system in-situ crystallization process. Several features of the mineral chemistry (e.g. positive correlation of (La/Sm) N with La and Na in clinopyroxene and plagioclase, respectively) support the involvement of an external component (wall-rock assimilation or hybridization with an evolved melt). The petrography and mineral chemistry of the gabbros, in conjunction with bulk rock data from previous studies, favour a calc-alkaline affinity for the parental melts. Thus, metasomatism in the mantle sources related with this basic magmatism might be associated with recycling of crustal components during the Variscan orogeny.Keywords: Late orogenic gabbros, late-stage crystallization, Spanish Central System, Variscan Orogeny, calc-alkaline magmas Resumen Se ha caracterizado la composición química de elementos mayoritarios y trazas en los minerales principales de las intrusiones gabroideas de Talavera y La Solanilla (Sistema Central Español). Los resultados muestran una composición mineral heterogénea que es ilustrativa de una evolución química de los magmas básicos calco-alcalinos durante la cristalización. La formación de minerales intersticiales con elevados contenidos en elementos incompatibles, como por ejemplo el anfíbol, la flogopita y algunos minerales accesorios (circón, apatito...), y la presencia de zonados en los minerales principales, con tendencia a desarrollar una composición más evolucionada hacia el borde, indican la diferenciación progresiva del fundido parental. La variación química de elementos traza normalmente incompatibles en el clinopiroxeno (e.g., REE, Th, Zr, Nb, Ti) implica la co-precipitación de fases con un comportamiento compatible con dichos elementos (e.g., apatito, circón, anfíbol). Sin embargo, las elevadas concentraciones de LILE y LREE del clinopiroxeno no se pueden explicar exclusivamente por un proceso de cristalización en un sistema cerrado. Varias características de la química mineral (e.g., corr...

show abstract

Near-solidus evolution of oceanic gabbros: insights from amphibole geochemistry

Cited by 136 publications

References 38 publications

Plutonic xenoliths from Martinique, Lesser Antilles: evidence for open system processes and reactive melt flow in island arc crust

Plutonic xenoliths from Martinique, Lesser Antilles: evidence for open system processes and reactive melt flow in island arc crust

Root zone of the sheeted dike complex in the Oman ophiolite

Mineral chemistry of late Variscan gabbros from central Spain: constraints on crystallisation processes and nature of the parental magmas

Contact Info

Product

Resources

About