Academic literature on the topic 'Magmatism Nd-Sm-Sr-Hf isotopes'

Research subject. The isotopic composition (Pb-Pb, Sm-Nd, Rb-Sr, Os/Os, Hf/Hf, 3 He/4 He, etc.) of magmatic complexes and ore-magmatic systems (OMS) of two ore clusters (Kupolsky and Ilirneysky) located in the subpolar Western Chukotka was studied. These ore clusters differ from each other both in their structural position and the age of their magmatic complexes, within which the largest deposits of Au-Ag type are known. Materials and methods. The Pb-Pb, Rb-Sr, SmNd, Re-Os, Lu-Hf, 3 He/4 He, 40Ar/36Ar and sulphur isotopic systems were studied at the VSEGEI centre for isotopic studies (St. Petersburg), as well as at the Institute of Geology, Geochemistry and Ore Deposits (IGEM, Moscow) and the Laboratory of Stable Isotopes of the Far Eastern Geological Institute (FEGI, Vladivostok). Re and Os were measured using an ELEMENT-2 inductively coupled plasma single-collector mass spectrometer. Sulphur isotopic ratios were measured using a Finnigan MAT 253 isotope mass spectrometer. Results and conclusions. On the basis of the isotope-geochemical data obtained, an assumption was made that various deep sources participated in the magma generation, and the differentiated composition of late melts may reflect the melting processes of the crust upper horizons. When comparing the data on the magmatism of the Ilirneysky and Kupolsky ore clusters, a different degree of crustal rock influence on melt generation was revealed. The Kupolsky ore cluster is characterised by a large influence of mantle sources in intraplate magmatism associated with ore formation processes. This is likely to have determined a greater amount of mineralisation in the Kupolsky cluster compared to the Ilirneysky ore cluster.

Study of petrological and geochemical characteristics of mantle peridotite xenoliths in Pliocene alkaline basalt in Nghia Dan (West Nghe An) was carried out. Rock-forming clinopyroxenes, the major trace element containers, were separated from the xenoliths to analyze for major, trace element and Sr-Nd isotopic compositions. The data were interpreted for source geochemical characteristics and geodynamic processes of the lithospheric mantle beneath the region. The peridotite xenoliths being mostly spinel-lherzolites in composition, are residual entities having been produced following partial melting events of ultramafic rocks in the asthenosphere. They are depleted in trace element abundance and Sr-Nd isotopic composition. Some are even more depleted as compared to mid-ocean ridge mantle xenoliths. Modelled calculation based on trace element abundances and their corresponding solid/liquid distribution coefficients showed that the Nghia Dan mantle xenoliths may be produced of melting degrees from 8 to 12%. Applying various methods for two-pyroxene temperature- pressure estimates, the Nghia Dan mantle xenoliths show ranges of crystallization temperature and pressure, respectively, of 1010-1044°C and 13-14.2 kbar, roughly about 43km. A geotherm constructed for the mantle xenoliths showed a higher geothermal gradient as compared to that of in the western Highlands (Vietnam) and a conductive model, implying a thermal perturbation under the region. The calculated Sm-Nd model ages for the clinopyroxenes yielded 127 and 122 Ma. 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Lamproite is a rare ultrapotassic alkaline rock of petrological importance as it is considered to be derived from metasomatized lithospheric mantle, and of economic significance, being the host of major diamond deposits. A review of the nomenclature of lamproite results in the recommendation that members of the lamproite petrological clan be named using mineralogical-genetic classifications to distinguish them from other genetically unrelated potassic alkaline rocks, kimberlite, and diverse lamprophyres. The names “Group 2 kimberlite” and “orangeite” must be abandoned as these rock types are varieties of bona fide lamproite restricted to the Kaapvaal Craton. Lamproites exhibit extreme diversity in their mineralogy which ranges from olivine phlogopite lamproite, through phlogopite leucite lamproite and potassic titanian richterite-diopside lamproite, to leucite sanidine lamproite. Diamondiferous olivine lamproites are hybrid rocks extensively contaminated by mantle-derived xenocrystic olivine. Currently, lamproites are divided into cratonic (e.g. Leucite Hills, USA; Baifen, China) and orogenic (Mediterranean) varieties (e.g. Murcia-Almeria, Spain; Afyon, Turkey; Xungba, Tibet). Each cratonic and orogenic lamproite province differs significantly in tectonic setting and Sr–Nd–Pb–Hf isotopic compositions. Isotopic compositions indicate derivation from enriched mantle sources, having long-term low Sm/Nd and high Rb/Sr ratios, relative to bulk earth and depleted asthenospheric mantle. All lamproites are considered, on the basis of their geochemistry, to be derived from ancient mineralogically complex K–Ti–Ba–REE-rich veins, or metasomes, in the lithospheric mantle with, or without, subsequent contributions from recent asthenospheric or subducted components at the time of genesis. Lamproite primary magmas are considered to be relatively silica-rich (~50–60 wt.% SiO2), MgO-poor (3–12 wt.%), and ultrapotassic (~8–12 wt.% K2O) as exemplified by hyalo-phlogopite lamproites from the Leucite Hills (Wyoming) or Smoky Butte (Montana). Brief descriptions are given of the most important phreatomagmatic diamondiferous lamproite vents. The tectonic processes which lead to partial melting of metasomes, and/or initiation of magmatism, are described for examples of cratonic and orogenic lamproites. As each lamproite province differs with respect to its mineralogy, geochemical evolution, and tectonic setting there is no simple or common petrogenetic model for their genesis. Each province must be considered as the unique expression of the times and vagaries of ancient mantle metasomatism, coupled with diverse and complex partial melting processes, together with mixing of younger asthenospheric and lithospheric material, and, in the case of many orogenic lamproites, with Paleogene to Recent subducted material.

Subduction of the Paleo-Pacific slab beneath the North China Craton (NCC) has exerted a strong influence on the Mesozoic destruction of the craton. However, no Andean-type arc magmatism has been reliably identified in the eastern NCC. Here we report the occurrence of Jurassic arc-like lamprophyres in the Liaodong Peninsula, providing a snapshot of the Paleo-Pacific slab subduction beneath the NCC in the early Mesozoic. Zircon U-Pb dating of the lamprophyres yields consistent ages of 158−155 Ma for magma crystallization. These lamprophyres all exhibit typical arc-like trace element distribution patterns, but show a series differences in their radiogenic isotope compositions and the other geochemical variables. Type 1 lamprophyres exhibit weakly enriched Sr-Nd-Hf isotopes with (87Sr/86Sr)i ratios of 0.7075−0.7085, εNd(t) values of −3.9 to −1.3 and εHf(t) values of −5.4 to −0.3, whereas Type 2 lamprophyres exhibit moderately enriched radiogenic isotopes with (87Sr/86Sr)i ratios of 0.7096−0.7117, εNd(t) values of −12.2 to −7.6 and εHf(t) values of −12.8 to −4.7. There are also systematic differences in zircon Hf isotopes and whole-rock Ba/Th, Ba/La, Sr/Nd, Th/Nd, Th/Yb, and La/Sm ratios for the two types of lamprophyre. Taken together, these similarities and differences can be accounted for by metasomatic reaction of the cratonic mantle wedge with two properties of liquid phase derived from subducting Paleo-Pacific slab. One is aqueous solutions from the subducting basaltic oceanic crust, and the other is hydrous melts from the subducting terrigenous. The two properties of subduction zone fluids were incorporated in different proportions into the mantle sources of these lamprophyres. Accordingly, the lamprophyres were derived from the metasomatic mantle sources. This qualitative interpretation is verified by quantitative modeling of the geochemical transfer at the slab-mantle interface in a paleo-oceanic subduction zone. Therefore, the Jurassic lamprophyres in the eastern NCC provide the geochemical evidence for the crust-mantle interaction during the Paleo-Pacific slab subduction beneath eastern Asia in the early Mesozoic, when the chemical metasomatism by the slab-derived fluids would have weakened the cratonic mantle for its thinning and destruction in the Early Cretaceous.

Abstract Magmatic Ni-Cu-platinum group element (PGE)-Te mineralization in the Gondpipri mafic-ultramafic layered intrusion of ca. 3323 ± 74 Ma age, western Bastar craton, central India, is one of the most prospective exploration targets for magmatic sulfides in India. The Gondpipri layered intrusion is divided into two distinct group of rocks based on their mineralization potential, which includes (1) mineralized layered gabbro and pyroxenite and (2) a barren olivine gabbro intrusion. The host rocks show Cu + Ni concentrations up to 5,000 ppm with a Cu/Ni ratio <1 and all platinum group element (PGE) values between 0.1 and 1.1 ppm. Mineralization occurs in two modes: type I mineralization occurring as blebs, specks, and dissemination and type II mineralization occurring as stringers and minor veins. The geochemical data suggest that the parental magma of the host rock was generated at depths between spinel and garnet peridotite mantle source regions and subsequently modified by assimilation fractional crystallization (AFC) of the continental crust. High large ion lithophile elements, Th/Yb ratios of the studied rocks, and Sm-Nd isotope studies are consistent with a depleted mantle source. The geochemical proxies such as Th versus Ba/Th and (Ta/La)PM versus (Hf/Sm)PM and higher Sr/Nd (2.21–82.58) ratios indicate involvement of fluid-related subduction metasomatism and enrichment processes in an island-arc tectonic setting. Mineral assemblages and textural relationship between platinum group minerals (PGMs) and base metal sulfides suggest that sulfide-silicate liquid immiscibility was brought about by the precipitation of magnetite/Cr magnetite resulting in sulfide saturation in the melt by decreasing S solubility. Sulfur isotope compositions (δ34S: 1.61–3.30‰) and Sm-Nd geochemistry suggest that the sulfur was added in the tholeiitic magma by magmatic process. Crustal contamination played a significant role in sulfide saturation and in bringing about PGE and Te, As, Bi, Sb, Se (TABS) mineralization. PGM-NiTeBi developed at relatively low temperatures, where moncheite (PtPd)Te2 and merenskyite (PdTe) were formed at 650°C. The identification of Ni-Cu-PGM-Te in the margin of the western Bastar craton boosts deeper subsurface exploration.

Knowledge of the subduction to postcollision tectonic transition in response to oceanic closure is crucial for tracking the final stage of orogenic evolution. Here, we report new geochronology, geochemistry, and isotopic data for Carboniferous magmatism in East Junggar (NW China), southwestern Central Asian orogenic belt, which may record such processes following the closure of the Kalamaili Ocean (a branch of the Paleo-Asian Ocean). The early Carboniferous calc-alkaline volcanic rocks (dominated by basalt and basaltic andesite) yielded zircon U-Pb ages of ca. 340−330 Ma and are characterized by arc-like trace-element patterns showing enrichment of light rare earth elements (LREEs) and large ion lithophile elements (LILEs; e.g., Pb) but depletion of high field strength elements (HFSEs; e.g., Nb, Ta, and Ti). Combined with their variable Ba/Nb (9.80−454) and low Nb/La (0.21−0.54) and Sm/Yb (1.77−3.08) ratios as well as depleted mantle−like Sr-Nd-Pb-Hf (whole-rock 87Sr/86Sri = 0.7037−0.7040; ɛNd[t] = +3.5 to +5.9; 206Pb/204Pbi = 17.728−17.996; zircon ɛHf[t] = +11.8 to +18.8) isotopic values, we suggest that they were produced by melting of a lithospheric mantle wedge fluxed by slab-derived fluids under spinel-facies conditions. With whole-rock 40Ar/39Ar dating of ca. 320 Ma, the late Carboniferous mafic dikes have geochemical features and Sr-Nd-Pb (87Sr/86Sri = 0.7039−0.7041; ɛNd[t] = +6.6 to +6.8; 206Pb/204Pbi = 17.905−17.933) isotopic compositions similar to those of the early Carboniferous volcanics, but they show less pronounced Pb anomalies and negative Nb and Ta anomalies. They are interpreted to have formed by partial melting of a spinel-bearing lithospheric mantle metasomatized by limited influx of subduction-related fluids. The late Carboniferous felsic volcanic rocks (dacite and rhyolite) yielded zircon U-Pb ages of ca. 305 Ma and are geochemically equivalent to those of A2-type granites in East Junggar. They have juvenile isotopic compositions (ɛNd[t] = +4.5 to +6.8; ɛHf[t] = +13.3 to +18.7) and relatively young Nd and Hf model ages that roughly coincide with the ages of the ophiolites in the area, suggesting that they could have originated from melting of a juvenile basaltic lower crust. Whole-rock geochemistry, assimilation−fractional crystallization (AFC), and isotopic mixing modeling argue for insignificant crustal contamination for the Carboniferous magmatism. We suggest that the early Carboniferous lavas erupted in an island-arc setting related to the northward subduction of the Kalamaili oceanic crust, whereas the late Carboniferous magmatism formed in a postcollisional extensional regime in response to slab breakoff or lithospheric delamination. Combined with regional geological information, we propose that a rapid tectonic transition from oceanic subduction to postcollisional extension may have occurred in East Junggar during the Carboniferous, marking the final closure of the Kalamaili Ocean, which most likely took place ca. 330−320 Ma. This study provides overall geochronological and petrogeochemical evidence to better constrain the amalgamation of the southwestern Central Asian orogenic belt and may be of great importance for understanding the final stage of orogenic evolution elsewhere.

Abstract The temporal and spatial distribution of enriched source components at sites of continent–continent collision provides critical insights into mantle dynamic processes associated with subduction- and collision-related events. However, determining the origin of such enriched components remains a significant challenge. We report a comprehensive dataset of the Linzizong volcanic succession (LVS) from four locations with varying distance across-strike to the Indus–Yarlung suture in southern Tibet, which marks the exposed surface expression of the India–Asia collision zone. The LVS rocks in this study can be divided into two groups: a calc-alkaline Group 1 (69–55 Ma), mainly including basaltic–andesitic varieties, and a shoshonitic Group 2 (52–50 Ma), consisting predominantly of silicic rocks with minor mafic compositions. Group 1 samples are likely derived from the fractional crystallization of primitive basaltic melts as a result of the partial melting of a metasomatized mantle wedge. These samples are decoupled in Nd–Hf isotopic compositions, suggesting an incorporation of subducting sediment-derived melts into the mantle wedge. The influence of sediment-derived melt on the mantle source increases away from the suture zone toward Asia (i.e., from the south to the north) as indicated by the more enriched Sr, Nd, Pb, and Hf isotopic compositions, as well as elevated Th/La and La/Sm ratios. The heavy δ26Mg values, and high Ba/Th and Sr/Th ratios of samples close to the suture coincide with the dehydration of the subducting Neo-Tethyan slab. Group 2 mafic samples have depleted and coupled εNd–εHf isotopic compositions and are characterized by elevated (La/Yb)N and Dy/Yb ratios as well as low Zr/Nb ratios, indicating an origin of enriched garnet-bearing lithospheric mantle with contributions from asthenosphere-derived materials. Group 2 silicic samples are isotopically enriched both near and far away from the suture, which can be attributed to the involvement of ancient lower crust-derived melt from Tethyan Himalaya and central Lhasa subterrane basement, respectively. Our results show that the LVS are the magmatic response to late subduction (Group 1), and to initial India–Asia collision and slab breakoff (Group 2). Negative trends in the whole-rock Nd and zircon Hf isotopic compositions at ~51 Ma should be treated with caution for geodynamic interpretations, depending on the distance between the samples and the India–Asia suture.

Abstract Daqingshan is located in the northwestern North China Craton where late Neoarchaean supracrustal rocks occur widely, but where magmatic zircon ages have rarely been reported for plutonic rocks. In this study, we report SIMS U–Pb zircon ages and Hf isotope, whole-rock element and Nd isotope compositions for 12 magmatic samples, including TTG, quartz monzonitic and monzogranitic gneisses, and meta-gabbroic and dioritic rocks. They have magmatic zircon ages of 2530–2469 Ma; some samples have ages of <2.48 Ga likely influenced by late Palaeoproterozoic tectonothermal events, making their ages less reliable. TTG gneisses have low Sr/Y and La/Yb ratios, with whole-rock ϵNd(t) and in situ magmatic zircon ϵHf(t) values of +1.2 to +2.4 and −1.1 to +6.2, respectively. Quartz monzonite and monzogranite gneisses and gabbroic to dioritic rocks have similar Nd–Hf isotope compositions to the TTG gneisses. The absence of zircon >2.6 Ga in the early Precambrian rocks suggests that the Sanggan Group may have formed in an oceanic environment, whereas the TTG rocks formed as a result of partial melting of the basaltic rocks of the Sanggan Group under relatively low-pressure conditions. Combined with previous studies, the main conclusions are that in the Daqingshan area, late Neoarchaean magmatism was widespread, the late Mesoarchaean – early Neoarchaean was an important period of juvenile continental crustal growth, and the late Neoarchaean supracrustal and plutonic rocks most likely formed in an arc environment. These are common signatures for Neoarchaean crustal evolution throughout much of the North China Craton, and also globally.

The University foidolite-gabbro pluton is located among the Cambrian carbonate-volcanogenic deposits. Its composition is dominated by moderately-alkaline and alkaline mafic rocks, broken by dikes of ijolite-urtites, nepheline and alkaline syenites. The chemical composition of igneous rocks is characterized by low silica contents (SiO2 = 41–49 wt. %), wide variations of alkalinity (Na2O + K2O = 3–19 wt. %; Na2O / K2O = 1.2–7.2 wt. %), low titanium content (TiO2 = 0.07 1.59 wt. %) and high alumina content (Al2O3 = 15–28 wt. %), which corresponds to the K-Na derivatives of the basic alkaline formation. By the content of rare earth elements, alkaline rocks (104–246 ppm; La/Yb(n) = 5.79–12.73) are more differentiated derivatives than gabbro (94–111 ppm; La/Yb(n) = 6.87‑6.95). All varieties are characterized by low concentrations of most highly charged elements (Nb, Ta, Zr, Hf + Y), which in terms of accumulation are located between the basalts of oceanic islands and basalts of island arcs. The presence of negative Nb–Ta anomaly and the relative enrichment of Rb, Ba, Sr, and U indicate the probable interaction of plume material with previously formed accretionary complexes of subduction zones. The primary isotope 87Sr/86Sr ratio (~ 0.705 – 0.706) and a wide range of εNd (T) from +3.2 to +8.7 in the rocks also indicate a mantle-crustal nature and a complex geodynamic setting of the Paleozoic alkaline magmatism of the Kuznetsk Alatau. The obtained results of Sm‑Nd dating suggest the formation of moderately-alkaline gabbroids in the Early Paleozoic (494–491 ± 36 Ma), with the intrusion of dikes of alkaline rocks of the Middle Paleozoic age (394 ± 16 and 389 ± 37 Ma).

The Tarim craton in modern Central Asia was an important component of the supercontinent Rodinia in the Neoproterozoic, although its paleogeography in Rodinia during that era is still controversial. Here, we present new stratigraphic, geochemical, and geochronological data from the Neoproterozoic sedimentary and volcanic rock successions along the northwestern margin of the Tarim craton and discuss the significance of these data and our interpretations for its tectonic evolution and paleogeographic position within Rodinia. The Lower Ediacaran sedimentary sequence (Sugetbrak Formation) in northwest Tarim includes terrestrial and shallow-marine clastic rocks intercalated with two discrete basaltic lava flows near the top. The Upper Ediacaran sedimentary sequence conformably overlying the volcanic and clastic rocks consists mainly of stromatolitic dolomite (Chigebrak Formation), representing a transgressive shallow-marine environment. Previous U-Pb zircon dating of the basaltic lava flows has constrained the timing of their eruption in the early Ediacaran (615 Ma). Detrital zircon U-Pb dating of a feldspar-quartz-sandstone unit situated between the two lava flows revealed an oldest age of 2517 ± 18 Ma and a youngest age of 612 ± 6 Ma, with a majority of zircon grains (n = 42) dated at 891−754 Ma (Tonian). A quartz-sandstone unit above the upper lava flow revealed an oldest age of 2724 ± 15 Ma and a youngest age of 607 ± 8 Ma, with a missing age group of 891−800 Ma. These data and observations indicate: (1) a major switch in the depositional setting from a terrestrial (synrifting) to shallow-marine environment following the eruption of the upper lava unit; and (2) an abrupt disappearance of the source rocks of the 891−800 Ma zircons and sediments from the provenance of the post-615 Ma (postrifting) sedimentary sequence. The basaltic rocks have low SiO2 and MgO but high total Fe2O3 and TiO2 contents (2.34−3.19 wt%), analogous to high-Ti basalts and continental flood basalts. Their Ti/V ratios (65−88), low Th/Nb ratios (∼0.1), and high TiO2/Yb ratios (∼1.1) are similar to those of ocean-island basalt (OIB). Combined with their Sm/Yb and La/Sm ratios and Sr-Nd-Pb-Hf isotope values, we infer that magmas of the Sugetbrak basalts were likely derived from partial melting of an enriched mantle source (EM I) in a transitional spinel-garnet lherzolite field. This petrogenetic evolution was a result of mantle plume−influenced rift magmatism during the Ediacaran breakup of Rodinia. The Central Tianshan terrane, which was attached to the northern Tarim craton until the Ediacaran Period, was the provenance of 891−800 Ma (Tonian) zircons in the synrift sedimentary succession. As the Central Tianshan terrane broke away from the Tarim craton after ca. 615 Ma, Tonian-aged zircons were no longer available to the depocenter of the postrift sedimentary sequence. The transition from rifting to drifting between the Tarim craton and the Central Tianshan terrane marked the final breakup of Rodinia, a global event that was possibly driven by mantle plume activities coeval with the development of the Central Iapetus magmatic province in Laurentia during the Ediacaran.

The Arabian-Nubian shield reflects the complex interplay between juvenile oceanic and continental arc fragments accreted during the final stages of Gondwanian super continental assembly. To date, much of the geochronological and geochemical data from the Arabian Shield, Saudi Arabia, is absent or poorly constrained and extrapolated from neighbouring Middle Eastern and African countries. Little attention has been paid to the petrogenesis and tectonic significance of the plutonic rocks pursuant to lithospheric orogenesis. A total of 137 samples from 26 geological units were collected from the Midyan, Hijaz, Asir, Tathlith, Afif, Ad Dawadimi and Ha’il terranes with particular emphasis on accretionary suture zone and within plate setting relationships. Extensive data bases are constructed using zircon U-Pb geochronology and Hf isotopes to evaluate Gondwanian significance and whole rock major and trace element geochemistry, Nd, Sm, Sr isotopes and zircon geochemistry to determine their petrogenetic properties. These parameters provide new insight into changing mantle conditions beneath collisional sutures (Yanbu, Nabitah and Halaban) and within plate asthenospheric upwelling. 19 granitic units are subdivided into metaluminous, peraluminous and peralkaline groups that possess distinguished island arc (~950-730Ma), syncollisional (~<730-636Ma), post tectonic (~<636-600Ma) and anorogenic (<600Ma) U-Pb geochronology. These magmatic phases represent accretionary cycles initiating from the dismantlement of Rodinia, closure of the Mozambique Ocean and final Gondwana amalgamation. Evidence for final assembly is recorded at ~525Ma (Najd fault reactivation) which is now the youngest dated magmatism in the Arabian-Nubian Shield and warrants repositioning of the regional unconformity at ~542Ma. Emplacement of sampled Arabian Shield classic A-type post-tectonic and anorogenic granitoids falls into three categories: 1) Intrude sutures immediately following collision which contain extensive mafic cumulate fractionation and N-MORB affiliation. 2) Plate boundary juxtaposed suites without obvious mafic cumulates, but posses contaminated N-MORB geochemistry. 3) Within plate granitoids isolated from plate boundaries and also without obvious mafic cumulates, but with a distinctive enriched (OIB) like asthenospheric mantle source. All categories produce similar felsic endmembers, but contain isotopically distinct mantle source. These are differentiated using a newly developed geochemical scheme (contaminated and enriched mantle granitoids) that is successfully applied to regional Arabian-Nubian examples. The diachronous Nabitah Orogenic Belt symbolises collision and subduction between western oceanic and eastern continental terranes that was terminated by the appearance of category 1 post-tectonic granitoids. This long lived (~50Ma) granitic magmatism contains mingling textures, discrete crystallisation ages, distinguished zircon morphologies and isotopically less juvenile mafics that geochronologically and geochemically reflect magmatic pulsing from a contaminated lower crustal MASH zone. The transition from N-MORB like mafics to isotopically enriched granitoids (isotopically similar to category 3 suites) reflects subduction magmatism followed by slab tear and asthenospheric influx. Conversely, the appearance of category 3 anorogenic plutons is characterised by widespread, tightly constrained (<10Ma) magmatism that is geochemically enriched, economic and symbolic of lithospheric delamination and asthenospheric (OIB like) upwelling. Differences between category 1, 2 and 3 zircon geochemistry constrain further contaminated and enriched mantle source behaviour that produces similar felsic products from distinguished petrogenetic processes. In summary, the work presented in this thesis establishes clear distinctions between accretionary syncollisional suites and anorogenic suites, but more significantly, post-orogenic plutons confined to suture zones from those confined to within plate settings. This allows new petrogenetic insights into changing juvenile mantle beneath the Arabian Shield.
Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2014