Rare earth element geochemistry of the Scourian complex N.W. Scotland ? Evidence for the granite-granulite link

Pride, C.; Muecke, G. K.

doi:10.1007/bf00376632

Cited by 76 publications

(27 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar patterns are reported' from garnetiferous mafic granulites (Pride and Muecke, 1980) in the Lewisian at Scourie, from the Fiskenaesset amphibolites, West Greenland (Weaver et al, 1982), and from present day N-type Rollinson, 1978;Sills et al, 1982). middle to heavy REE [(Ce/Sm), = 1.57); (Gd/ Yb)n --2.54] (Fig.…”

Section: Primary Geochemistrysupporting

confidence: 81%

Early basic magmatism in the evolution of Archaean high-grade gneiss terrains: an example from the Lewisian of NW Scotland

Rollinson¹

1987

Mineral. mag.

View full text Add to dashboard Cite

Amphibolite blocks from an Archaean (2.9 Ga) trondhjemite-agmatite complex in the Lewisian at Gruinard Bay have a varied trace element and REE content. Whilst some of the variability is attributable to element mobility during high-grade metamorphism and subsequent trondhjemite magmatism, it is for the main part considered to be a primary feature of the amphibolites. The observed trace element and REE chemistry is best explained in terms of source region heterogeneity and suggests a melting regime comparable with that beneath certain types of mid-ocean ridge. There are geochemical similarities between the amphibolites and the Lewisian layered gabbro-ultramafic complexes, and the two may represent the derivative liquid and associated cumulates respectively from a common parent magma. Thus there is a parallel between the processes which generated some Archaean amphibolites and layered gabbro complexes and those operating beneath modern ocean ridges. Hornblendite and amphibolite pods enclosed within tonalitic gneiss, also found as blocks in the agmatite complex, are geochemically distinct from the main group of amphibolites and are probably of calc-alkaline parentage.K E Y w 0 R D S : magmatism, gneiss, amphibolite, Lewisian, Scotland.

show abstract

Section: Primary Geochemistrysupporting

confidence: 81%

Early basic magmatism in the evolution of Archaean high-grade gneiss terrains: an example from the Lewisian of NW Scotland

Rollinson¹

1987

Mineral. mag.

View full text Add to dashboard Cite

show abstract

“…Variations in La N /Yb N ratio, graphically represented on Fig. 2, are consistent with the trends for normal, cogenetic igneous rock sequences (Pride and Muecke, 1980). The La N /Sm N ratios, plotted on Fig.…”

Section: Sampling Analytical Methods and Resultssupporting

confidence: 55%

Rare-earth elements as source indicators of Pan-African granites from Obudu Plateau, Southeastern Nigeria

Ukaegbu

Beka

2008

Chin. J. Geochem.

View full text Add to dashboard Cite

The rare-earth element (REE) concentrations of representative granite samples from the southeast of the Obudu Plateau, Nigeria, were analyzed with an attempt to determine the signatures of their source, evolutionary history and tectonic setting. Results indicated that the granites have high absolute REE concentrations (190×10 -6 -1191×10 -6 ; av.=549×10 -6 ) with the chondrite-normalized REE patterns characterized by steep negative slopes and prominent to slight or no negative Eu anomalies. All the samples are also characterized by high and variable concentrations of the LREE (151×10 -6 -1169×10 -6 ; av.= 466×10 -6 ), while the HREE show low abundance (4×10 -6 -107×10 -6 ; av.=28×10 -6 ). These are consistent with the variable levels of REE fractionation, and differentiation of the granites. This is further supported by the range of REE contents, the chondrite-normalized patterns and the ratios of La N /Yb N (2.30-343.37), Ce N /Yb N (5.94-716.87), La N /Sm N (3.14-11.68) and Tb N /Yb N (0.58-1.65). The general parallelism of the REE patterns, suggest that all the granites were comagmatic in origin, while the high Eu/Eu* ratios (0.085-2.807; av.=0.9398) indicate high f O2 at the source. Similarly, irregular variations ratios and REE abundances among the samples suggest behaviors that are related to mantle and crustal sources.

show abstract

“…1984;Pride and Muecke 1980). O n e important aspect concerns the distinctive chemical nature of the lower crust, notably its proposed tonalitic composition (Weaver and Tarney 1984) and marked depletion in large-ion lithophile elements (LILEs, including Th, U , K and Rb-Heier and Adams 1965;Rudnick et al 1985).…”

Section: Introductionmentioning

confidence: 98%

“…Ben O t h m a n et al. 1984;Pride and Muecke 1980) attribute this to partial fusion of an upper crustal protolith, generating LILE-enriched granitic melts which migrate upwards to form high level plutons and leave a complementary residue of "depleted" granulites at depth (i.e. intracrustal partial melting or the restite model).…”

Section: Introductionmentioning

confidence: 98%

“…Geochemical investigations to date have been concerned with these "endmembers" of the range of metamorphic variation (e.g. Weaver andTarney 1980, 1981;Pride and Muecke 1980, 1982Rollinson and Windley 1980a, b). However, in the region of Gruinard Bay, at the southern margin of the Scourian Complex of the mainland Lewisian outcrop (Sutton and Watson 1951;Rollinson and Fowler 1987), a transitional terrain is preserved where mineral assemblages of hornblende-granulite sub-facies were formed at the peak of the Scourian metamorphic event (Fowler 1985).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Rare earth element geochemistry of Lewisian grey gneisses from Gruinard Bay

Fowler

Plant

1987

SJG

View full text Add to dashboard Cite

Synopsis Previous work has suggested that Lewisian grey gneisses from Gruinard Bay suffered hornblende-granulite sub-facies Badcallian meta-morphism, during which depletion of the large-ion lithophile elements (K, Rb, U and Th) proceeded to a degree intermediate between amphibolite-facies and pyroxene-granulite-facies counterparts. Rare earth element data for the gneisses are presented here, and used to test current theories of Lewisian petrogenesis, including the processes responsible for the observed LILE depletion. Intracrustal partial melting—as recently applied to the type Scourian pyroxene-granulites—is shown to be inappropriate to the specific conditions leading to an amphibole-bearing (hornblende-granulitic) residue, such as that required at Gruinard Bay. On the other hand, hydrous melting of Archaean tholeiite, retaining a mineralogically variable eclogitic residue, is apparently capable of accurately reproducing the REE patterns of the gneiss suite, especially when coupled with local amphibole fractionation. This model requires a subsequent phase of LILE loss during metamorphism.

show abstract

Rare earth element geochemistry of the Scourian complex N.W. Scotland ? Evidence for the granite-granulite link

Cited by 76 publications

References 39 publications

Early basic magmatism in the evolution of Archaean high-grade gneiss terrains: an example from the Lewisian of NW Scotland

Early basic magmatism in the evolution of Archaean high-grade gneiss terrains: an example from the Lewisian of NW Scotland

Rare-earth elements as source indicators of Pan-African granites from Obudu Plateau, Southeastern Nigeria

Rare earth element geochemistry of Lewisian grey gneisses from Gruinard Bay

Contact Info

Product

Resources

About