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Deep-seated xenoliths entrained in the Hannuoba basalts of the northern Sino-Korean Craton include mafic and felsic granulites, mantle wall-rock from spinel- and garnet-spinel peridotite facies, and basaltic crystallisation products from the spinel-pyroxenite and garnet-pyroxenite stability fields. The mineral compositions of the xenoliths have been used to estimate temperatures and, where possible,...
Xenolith-bearing Neogene basalts occur in Hebi county, at the southern end of the Taihangshan-Luliangshan paleo-rift zone in the North China block of the Sino-Korean craton. This locality lies on the North-South Gravity Lineament, which divides the craton into two geophysical zones. The spinel peridotite xenoliths hosted by the basalts can be divided into two groups based on the Mg # values...
Spinel peridotite xenoliths recovered from the Tubaf and Edison volcanoes, south of Lihir Island in the Tabar-Lihir-Tanga-Feni island arc in Papua New Guinea, are predominantly fresh, refractory harzburgites. Many of the harzburgite xenoliths have cross-cutting vein networks and show evidence of modal metasomatism. These metasomatic veins contain a secondary mineral assemblage consisting of fibrous,...
Olivine crystal size distributions (CSDs) have been measured in three suites of spinel- and garnet-bearing harzburgites and lherzolites found as xenoliths in alkaline basalts from Canary Islands, Africa; Victoria Land, Antarctica; and Pali Aike, South America. The xenoliths derive from lithospheric mantle, from depths ranging from 80 to 20 km. Their textures vary from coarse to porphyroclastic and...
Mantle-derived garnet and spinel peridotite xenoliths and xenocrysts from the Daoxian basalts (151-131 Ma) and the Anyuan lamprophyres (~44 Ma) provide insights into the nature and evolution of subcontinental lithospheric mantle beneath the Cathaysia block, SE China. The Daoxian area lies astride the translithospheric Ningyuan-Jianghua fault zone in western Cathaysia, whereas the Anyuan area lies...
Some highly depleted harzburgitic mantle xenoliths from two different localities in the Kerguelen Islands display a secondary mineral assemblage unusual for both oceanic and continental settings. Petrographic and chemical evidence indicate reaction of primary orthopyroxene and spinel with an infiltrating melt to form Na-Cr-rich clinopyroxene+olivine+Cr-rich spinel+/-apatite+/-rutile+/-carbonate and...
The mantle xenolith suite from Tallante (Betic Cordillera, southern Spain) comprises peridotites equilibrated in the spinel to plagioclase stability field, ranging in composition from fertile lherzolites to harzburgites residual after partial melting events that occurred in pre-Paleozoic times. Evidence of superimposed metasomatic effects can be attributed to at least two metasomatizing agents with...
Mantle xenoliths and xenocrysts were retrieved from three of the 88-86 Ma Buffalo Hills kimberlites (K6, K11, K14) for a reconnaissance study of the subcontinental lithospheric mantle (SCLM) beneath the Buffalo Head Terrane (Alberta, Canada). The xenoliths include spinel lherzolites, one garnet spinel lherzolite, garnet harzburgites, one sheared garnet lherzolite and pyroxenites. Pyroxenitic and wehrlitic...
Geochemical data are presented for primitive alkaline rocks from the Kutch region, north–northwest of Deccan Volcanic Province (DVP) of west central India, which is generally regarded as related to the Reunion Plume. The trace element systematics of these rocks are similar to those of ocean-island basalts, but there is considerable compositional variation, which is related to a strong overprint from...
In order to provide mantle and crustal constraints during the evolution of the Colombian Andes, Sr and Nd isotopic studies were performed in xenoliths from the Mercaderes region, Northern Volcanic Zone, Colombia. Xenoliths are found in the Granatifera Tuff, a deposit of Cenozoic age, in which mantle- and crustal-derived xenoliths are present in bombs and fragments of andesites and lamprophyres compositions...
Coarse-grained, granular spinel lherzolites xenoliths from the Premier kimberlite show evidence of melt extraction and metasomatic enrichment, documenting a complex history for the shallow mantle beneath the Bushveld complex. Compositions of orthopyroxene, clinopyroxene and spinel indicate equilibration within the spinel–peridotite facies of the upper mantle, at depths from 80 to 100 km and temperatures...
The Neoproterozoic (∼ 820 Ma) Aries micaceous kimberlite intrudes the central Kimberley Basin, northern Western Australia, and has yielded a suite of 27 serpentinised ultramafic xenoliths, including spinel-bearing and rare, metasomatised, phlogopite–biotite and rutile-bearing types, along with minor granite xenoliths. Proton-microprobe trace-element analysis of pyrope and chromian spinel grains derived...
Mantle xenoliths from the Olot volcanic district (NE Spain) comprise a bi-modal suite consisting of protogranular spinel lherzolites (cpx 12–14%) sometimes with pargasitic amphibole, and highly refractory spinel harzburgites (cpx≤1%) with coarse-grained granular textures. The lherzolites range from slightly depleted to moderately LREE-enriched with flat HREE patterns between 1.5 and 2.7×chondrite...
The composition and geochemical signatures of the mantle wedge beneath the Lesser Antilles arc are documented by the ultramafic xenoliths included in alkali basalts (M-series) on Grenada. Xenoliths consist of harzburgites, lherzolites, dunites and subordinate wehrlites and pyroxenites. Primary minerals phases are olivine, low-Al and high-Al orthopyroxene, clinopyroxene and Cr-Spinel. In addition to...
At Mt. Vulture volcano (Basilicata, Italy) calcite globules (5–150 μm) are hosted by silicate glass pools or veins cross-cutting amphibole-bearing, or more common spinel-bearing mantle xenoliths and xenocrysts. The carbonate globules are rounded or elongated and are composed of a mosaic of 2–20 μm crystals, with varying optical orientation. These features are consistent with formation from a quenched...
The Monglo adakite contains mafic and ultramafic xenoliths, which probably originated from the mantle section of an Early Cretaceous supra-subduction zone ophiolitic complex located within the Luzon arc crust. Spinel-bearing dunites are dominant among this xenolith collection and display evidence for three episodes of subduction-related melt percolation. The first one is evidenced by an undeformed...
Concentrations of Li, Be and B and the isotopic composition of lithium have been measured in minerals from a suite of dry and metasomatised spinel peridotite and pyroxenite xenoliths from Harrat Uwayrid, a Pliocene–Quaternary volcanic field in the NW part of the Arabian peninsula, developed during formation of the Red Sea. In most peridotites, Li concentrations in pyroxene and olivine grains show...
A suite of mantle ultramafic xenoliths hosted in Cenozoïc alkali basalts and pyroclastic rocks associated with a back-arc tectonic environment occur at Cerro de los Chenques and Cerro Clark localities, North Patagonia (44.5–46.5°S). The suite of mantle xenoliths consists predominantly of anhydrous spinel-bearing lherzolites and olivine-bearing websterites. These two rock types share at least one stage...
A suite of mantle-wedge amphibole+phlogopite-bearing spinel peridotite xenoliths in Plio-Pleistocene alkali basalts from Southern Patagonia (Gobernador Gregores, Santa Cruz Province, Argentina) contains carbonic fluid inclusions, glass and carbonate in several textural domains. Here we present a microstructural and fluid inclusion study showing that fluid (corresponding to pure CO 2 ) and...
The Cape Verde Islands lie in the Atlantic Ocean off West Africa, in a clearly oceanic setting. The lavas of some islands carry mantle-derived xenoliths of depleted peridotites petrologically similar to those derived from cratonic lithospheric mantle. Oceanic lithospheric mantle, in contrast, consists mainly of less-depleted lherzolites and harzburgites formed by the extraction of mid-ocean ridge...
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