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The Oligocene Nasrand intrusive rocks (NIRs), located in the central part of the Urumieh–Dokhtar magmatic arc, are mainly composed of granite and subordinate diorite and gabbro. These rocks are characterized by the enrichment of light rare earth elements (LREEs), Nb‐Ta negative anomalies, and high LILE/HFSE, suggesting a subduction‐related origin. The felsic rocks with granite compositions have high SiO2 content (69.77–77.88 wt.%), low Mg# (0.02–0.43), low Nb/Ta, and Zr/Hf (Avg: 12.53, and 33.08, respectively). The initial 87Sr/86Sr ratio and εNd(t) values in felsic rocks range from 0.70577 to 0.70576 and 0.4 to −0.3, respectively. These data suggest that these felsic rocks originated from juvenile crust by heat rising from basaltic magmas in an orogenic setting. The mafic‐intermediate rocks and dikes are gabbro, gabbroic diorite, and monzodiorite, with low SiO2 content (48.08–56.11 wt.%) and high Mg# (0.37–0.68), with average ratios of Nb/Ta and Zr/Hf are 27.88 and 39.84, respectively. The initial 87Sr/86Sr ratio and εNd(t) values for mafic‐intermediate rocks and dikes are 0.70583 to 0.70476 and −0.1 to +2.6, respectively. These characteristics indicate magma from a mantle source that had undergone minor mixing with juvenile crust. It seems mantle‐derived juvenile magma underplating played an important role in the crustal growth in the Urumieh–Dokhtar magmatic belt during the Ediacaran to Early Cambrian, relative to other time frames. [ABSTRACT FROM AUTHOR]

Abstract Abundant tourmaline occurs in Late Triassic biotite-muscovite granites of Mashhad (NE Iran), with several distinct morphologies including tourmaline nodules in granite, pegmatitic tourmalines, aplitic tourmalines, and vein-related tourmalines (quartz-tourmaline vein, tourmaline-rich vein and radial tourmalines). Pegmatitic and aplitic tourmalines are compositionally Fe-rich schorl and the nodule, radial and vein tourmalines are Mg-rich schorl. The tourmalines have generally low abundances for most trace elements except for Sr, Ga, Li, Be, Sn, Pb and some transition elements. Tourmalines have low REE abundances and are enriched in LREE and depleted in HREE (mostly below detection limits) with positive Eu anomalies. The concentration of several trace elements (e.g., Pb, Be, Sn, Ga, Sr, Pb, and REE) correlates well with the major element composition of the tourmalines (e.g. Mg# (Mg/Mg + Fe), vacancy/)X-site vacancy + Na(and Na/)Na + Ca(). Trace element data of coexisting minerals with tourmaline indicate that the oligoclase and albite show the most preference in Sr, Pb and Eu and LREEs, biotite readily incorporates Rb, Ba, Zn, Li, Cs and Nb; K-feldspar has high contents of Rb, Ba, Sr and Pb; and garnet incorporates HREEs and Y during magma differentiation. The B-O-H isotopic compositions for all tourmalines are consistent with an S-type granite source, that was derived from partial melting of the continental crust. The pegmatitic and aplitic tourmalines with Fe-rich schorl composition indicate magmatic conditions and the radial, vein, and nodule tourmalines with Mg-rich schorl composition formed during the transition from magmatic to hydrothermal conditions due to the internal evolution of the granitic magma. Highlights • Various types of schorl-dravite tourmaline occur in Mashhad granite, NW Iran. • Mg-rich schorls have more Sr, La, Ce, Pr, Eu, Eu/Eu*, Nd and ∑REE than Fe-rich schorls. • Coexisting minerals with tourmaline show different trace element preferences. • The B-O-H isotopic compositions tourmalines are consistent with an S-type granite source. • Tourmaline formation records the evolution from magmatic transition to hydrothermal conditions. [ABSTRACT FROM AUTHOR]

Pegmatite-hosted garnets from four localities in the Boroujerd region, Lorestan (Western Iran), have been analysed for major and selected trace element compositions. The mineral assemblage of the granitic pegmatites is primarily quartz, plagioclase (albite), and alkali feldspar (orthoclase-microcline), as well as garnet, muscovite, fluorapatite, tourmaline (schorl-foitite), andalusite and zircon. The mineralogical and geochemical characteristics of the pegmatites indicate that they are peraluminous to slightly metaluminous I-type granites. Based on mineral assemblages and whole-rock geochemistry, the pegmatites are classified as muscovite-type pegmatites. Electron-probe micro-analysis reveals that garnets have concentric compositional zoning and are almandine-spessartine solid solutions with lesser pyrope, grossular and andradite components. Concentric zoning of major elements in the garnet is attributed to magmatic growth from a melt. On a MnO + CaO versus FeO + MgO (wt%) plot, the composition of garnet is consistent with crystallisation from weakly to moderately evolved melts. The garnets from the Boroujerd pegmatites are characterised by decreasing Y, HREE, Ti, Zr, Nb, Ta, Hf, and U abundances from core to rim. The garnets also have high chondrite normalized HREE abundances with nearly flat patterns (YbN/SmN = 0-508), lower LREE contents, and negative Eu anomalies (Eu/Eu* < 0.3). Variation in these elements from core to rim is attributed to increasing magma fractionation. The composition and major and trace element zoning patterns in the garnet of the Boroujerd pegmatites are compatible with a magmatic origin and crystallisation from variably fractionated I-type magmas demonstrating that garnet crystal-chemistry is an important tool for deciphering the origins of pegmatite magmas. [ABSTRACT FROM AUTHOR]

Nodular tourmalines composed of dark cores and white haloes occur in the Mashhad leucogranite. The cores are made up of tourmaline and quartz, and the haloes of quartz, muscovite, microcline and orthoclase. The host granite consists of quartz, plagioclase, microcline, muscovite and biotite. Geochemical analyses show that the studied tourmalines are schorl. They are characterized by oscillatory zoning, increasing concentrations of Ca and Mg from core to rim, moderate Fe/Fe + Mg ratios (56-63), and REE distribution patterns similar to those of the host granite. The tourmalines exhibit high Ti content due to breakdown of biotite. Petrographic and geochemical results show that the formation of tourmaline can be attributed to two stages. In the first stage, bubbles containing vapor-rich liquid, Fe, and B were generated by magma differentiation. During rise and cooling of the magma, core tourmaline was produced with Fe rich schorl composition. In the second stage, the tourmaline composition changed to that of Mg rich schorl because of the decomposition of biotite (biotite is considered as a source of Mg), and the mixing with vapor-rich liquid in bubbles [ABSTRACT FROM AUTHOR]

The Noorabad-Harsin ophiolite is a part of the eastern Mediterranean-Zagros-Oman Tethyan ophiolites. This area is located in the south-southwest of the main Zagros thrust zone. This ophiolite consists of peridotites, serpentinites and pegmatite gabbros as mantle sequence whereas crustal sequence is composed of locally layered gabbros, isotropic gabbros, sheeted dike complex, basaltic to andesitic lavas and sedimentary rocks (radiolarites and Late Cretaceous pelagic limestones). The diabase dikes are enriched in LREE relative to HREE (La(n)/Yb(n)=1.7-3.3). Also, the andesites are enriched in LREE relative to HREE (La(n)/Yb(n)=3.1-5.37) and the pillow lavas are enriched in LILE (Th(n)/La(n)=2.1) while show a depletion in HFSE (Nb(n)/La(n)=0.07-0.2). The basaltic-andesitic lavas exhibiting mainly calc-alkaline, with minor island-arc tholeiitic affinities, are characterized by enrichment in LILE and LREE and depletion in HFSE. These geochemical characteristics compared with other Tethyan ophiolites along the Bitlis-Zagros suture zone reveal a suprasubduction zone environment for the genesis of the Noorabad-Harsin ophiolites. [ABSTRACT FROM AUTHOR]

Abstract: The Astaneh plutonic complex consists of a series of granitoid rocks ranging in composition from quartz-diorites to monzogranites and evolving from metaluminous to weakly peraluminous compositions. They belong to the high-K calc-alkaline series, having features of typical Andean-type cordilleran granitoids. Trace and rare-earth elements distribution patterns for the Astaneh rocks indicate a distinctive depletion in Nb, Sr, Ba, P and Ti relative to other trace elements and a greater enrichment in LILE compared to HFSE. These geochemical characteristics suggest the participation of an important recycled (sedimentary?) component in the source region of the granitoids. They have Sr initial isotopic ratios in the range 0.7078–0.7084 and negative ε Nd values of −5.39 to −6.13 for a time of generation of 170Ma. There is a genetic link between quartz-diorites and granodiorites, the dominant rock types of the Astabeh intrusion. Direct melting or fractionation from a diorite source is very unlike. It is proposed that the Astaneh parental Qtd-diorite magmas were produced by the partial melting of a mixed source, dominantly composed of amphibolites and sediments, that was formed during subduction of Neo-Tethyan oceanic crust below the Iranian microcontinent during Middle Jurassic times. [Copyright &y& Elsevier]

The migmatites in the Boroujerd region, Western Iran are spatially associated with felsic and mafic magmatism. However, the genetic relationship between partial melting and magmatism in the region is unclear. Four metapelite migmatite samples (two melanosome and two leucosome) were selected for U-Pb zircon geochronology to determine the timing of anatexis. Major and trace element compositions of leucosome in the migmatites are consistent with being derived from biotite-breakdown partial melting of metapelites and not from the injection of granites associated with the Boroujerd igneous complex. Cores of zircon from metapelitic migmatite are inferred to be detrital in origin and yield ages of 320–250 Ma. The age of the detrital zircons is compatible with the timing of Paleozoic and Mesozoic magmatism in the Central Iranian micro-plate. The pelitic protolith of the migmatites in the Boroujerd region were probably originated from the Mesozoic continental margin of the Central Iranian microplate. Zircon rims and neoblastic grains yield ages of 220–210 Ma and 170–160 Ma. The geological significance of the older age population is unclear, but the younger population is similar to that of mafic and felsic intrusions in the area and is interpreted to record the general timing of high-temperature–low-pressure contact metamorphism and partial melting. We infer that the Middle Jurassic mafic and felsic magmatism was the principal heat source for the metamorphism and partial melting of the Boroujerd migmatites in response to the subduction of Neotethyan oceanic lithosphere. • Migmatites in the Boroujerd complex record high-temperature metamorphism. • Protoliths have maximum depositional ages of c 320–250 Ma. • The older metamorphism at c. 220 Ma was followed by partial melting at c. 170 Ma. • Jurassic mafic magmatism was the primary heat source for low-P–high-T anatexis. [ABSTRACT FROM AUTHOR]

The Almogholagh batholith in the northern Sanandaj-Sirjan magmatic–metamorphic zone comprises three intrusive bodies (gabbroic diorite, quartz syenite, and quartz monzonite) that were generated during the northeastward subduction of Neo-Tethys beneath the Iranian sector of the Eurasian plate. These bodies intruded at different time phases and are related to post-collision magmatism. The quartz syenite and quartz monzonite rocks with specifications of metaluminous, generally ferroan, alkalic to alkali-calcic types, high content of Na 2 O + K 2 O, Zr, Ce, Ga, Y, Nb, Ta, and rare earth elements, and depleted in Eu, Sr, and Ti show borderline characteristics between A 1 and A 2 types granitoids but with more affinity to A 2 type. The gabbroic dioritic rocks show borderline specifications between A 1 and I types rocks but with more affinity to I type. Distinctive spiked peak patterns in spider diagrams accompanied by (La/Yb) CN values equal to 2.44 to 6.11 and a Ba/La ratio >3 indicate the magmatism activity in the volcanic arc environment. The characteristics (Ba/Rb) PN < 1, (Ba/Th) PN < 1, and Th/Ta ratio from 3.18 to 8.42 suggest the magmatism activity of the continental margin setting. The specifications of post-collision magmatic activities, 143 Nd/ 144 Nd > 0.512638 in some samples, ε t Nd > 0, ε t Sr > 0, and high content of Nb, Ta, and Zr (589 ppm) demonstrate the involvement of the mantle source, subducted slab fluids, high flux of mantle-derived halogen-rich volatiles, and contamination within the crust during the petrogenesis of intrusions. After the initial collision, the operation of minor subduction (with slab break-off) or foundering of the lithospheric mantle (delamination) occurred because of asthenospheric upwelling and heat flows in the mantle in the Sanandaj-Sirjan zone. Stretch and local disruptions were created by these heat flows; simultaneously, magma was formed and ascended upward. [ABSTRACT FROM AUTHOR]

• There are 59 English-speaking countries in the world. • For 37 nations, the data on the regulations about driving and seizures were lacking. • Only the UK has made distinctions between epilepsy and FS. • Many nations have not made distinctions between private and commercial driving. We investigated the existing regulations about driving eligibility and restrictions for persons with seizures in all English-speaking countries in the world. We aimed to identify: 1) Is there a distinction between epilepsy and functional seizures (FS) in the regulations? 2) What is the required seizure-free period before a person with seizure regains their driving eligibility? First, we identified all the English-speaking countries in the world. Then, we referred to the website of the Department of Motor Vehicles or its equivalent in each nation or we searched the Google engine with the name of each specific nation and "driving" and "epilepsy". There are 59 English-speaking countries in the world. For 37 nations, the data on regulations about driving eligibility for persons with seizures were lacking. Only the UK has made distinctions between epilepsy and FS. The required seizure-free period before a person with seizure regains their driving eligibility varied significantly between nations. Not all nations have made distinctions between private driving and commercial driving. Finally, only some nations have specific rules and regulations for different scenarios (e.g., provoked seizures vs epilepsy, or nocturnal seizures only, etc.) Many English-speaking nations in the world do not have explicit rules and regulations about driving eligibility and restrictions for persons with seizures. International scientific organizations should do more to provide appropriate and personalized guidelines for different scenarios of seizures, so the governments can adopt appropriate regulations. [ABSTRACT FROM AUTHOR]