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Thorite, as a principally thorium (Th)-bearing mineral, is an important indicator for Th mineralization. However, its occurrence and enrichment processes are still discussed and debated. Here, a unique occurrence of thorite, discovered in Nubian granodiorite rather than in highly evolved granites from southwestern Egypt, is reported. This report presents data derived from optical and backscattered electron (BSE) microscopy and energy-dispersive X- ray spectrometry (EDS) analyses conducted on the thorite and its host rock. The Nubian granodiorite thorites are viewed as secondary, not primary products. Two distinct types of secondary thorites are identified that are referred to as type A thorite and type B thorite herein. Type A thorite occurs as small grains that are enclaved in a fine-grained matrix of altered oligoclase and ferrohornblende, and clinochlore. Thorite grains, up to 100 μm in size are characterized by corona-type structures comprising of clinochlore and hematite with some barite. Their sources are most likely hydrothermal solutions occurring during an alteration stage and having relatively high conditions of sulfate activity. Type B thorite, on the other hand, forms crystallites in altered domains of magmatic allanite-(Ce), ranging in size from ~ 0.1 to ~ 10 μm. Formation of Type B thorite is a direct result of fluid-driven alteration processes, since it requires the in situ-redistribution of elements, particularly thorium, silicon, and uranium. Thorite types A and B are composed mainly of thorium uranium silicate, with variable minor amounts of Y, Al, Ce, Nd, Fe, Ca, Na, Mg, P, and Cl. Thorite compositions are within the range reported for uranothorites from other occurrences. [ABSTRACT FROM AUTHOR]

ABSTRACT The North Qilian Accretionary Belt, situated at the northernmost extent of the Proto‐Tethys tectonic domain, preserves key tectonic events such as Proto‐Tethys Ocean subduction and accretion. Despite ongoing debates about the closure mechanisms and timing of the North Qilian Ocean, our study presents novel findings on granitoids from the Changma region in the western segment of the North Qilian Accretionary Belt. Zircon U–Pb dating indicates an emplacement age of 436 Ma for the Qingshixia pluton and 425 Ma for the Heixialao pluton. The εHf(t) values of the Qingshixia granodiorite range from +8.25 to +10.89, with TDM2 model ages estimated between 614 and 716 Ma. In contrast, the εHf(t) values of the Heixialao monzogranite range from +1.79 to +4.48, with TDM2 model ages spanning from 1127 to 1291 Ma. The Qingshixia granodiorite displays adakitic traits, characterised by high Sr, low Y, low Yb, and a low K2O/Na2O ratio, whilst the Heixialao monzogranite exhibits peraluminous, high‐potassium calc‐alkaline features. The low concentrations of Ni and Cr, along with moderate Mg# values, suggest that the Qingshixia granodiorite likely originated from the partial melting of a subducting slab. By comparison with experimental melts, the relatively low Rb/Ba and Rb/Sr ratios and higher zircon saturation temperatures of Heixialao monzogranite suggest that it may have formed from partial melting of the mafic middle and lower crust. Integrating these findings with regional geological features and differences between east and west segments, we propose that the western segment of the North Qilian Ocean basin may have closed during the Late Silurian, contributing to a diachronic closure process from east to west and offering insights into the tectonic evolution of the Proto‐Tethys Ocean. [ABSTRACT FROM AUTHOR]

The Sonkul and adjacent Kokturpak multiphase plutons are situated along the 'Major Structural Line of Tien Shan' (known also as the 'Nikolaev Line') that extends for over 500 km and divides the terranes of the Middle and Northern Tien Shan. The plutons comprise a broad variety of high-potassic igneous rocks including the early olivine gabbro, intermediate monzonite to quartz monzonite, and later granodiorite, monzogranite, and leucogranite-alaskite, in turn followed by the late mafic dikes. U-Pb dating of zircon grains yields ages of 299 ± 2 Ma (olivine gabbro), 300 ± 3 Ma to 298 ± 3 Ma (monzonite to quartz monzonite), 299 ± 3 Ma to 298 ± 4 Ma to 297 ± 4 Ma (granodiorite), and 289 ± 4 Ma to 285 ± 2 Ma (monzogranite). These consecutive intrusive phases appear to have been produced by partial re-melting of a partially crystallized (mush) magma batch at deeper levels, which is evident by the presence of zircon antecrysts dated at some 306–311 Ma (up to 323 Ma?). Geochemical signatures of the igneous rocks correspond to high-K calc-alkaline to shoshonitic series intrusions emplaced in a transitional subduction-related to post-collisional setting. A low-degree partial melting of the metasomatically enriched upper mantle can be envisioned as the leading process of shoshonitic magma generation; this was followed by amphibole fractionation in a deep (lower crustal ?) magma chamber and possibly a mantle-induced generation of granitic magmas in the crustal protolith. Further mixing/mingling of the mafic magma and crustal granitic magma was followed by the magma fractionation and emplacement at shallow crustal levels. Assimilation of the old continental crust is consistent with the presence of ancient xenocrystic zircons (dated at ca. 1.5 to 2.5 Ga) in the studied rocks. The Late Carboniferous to Early Permian age and high-K calc-alkaline to shoshonitic composition are similar to those of highly mineralized intrusions of the other segments of the Middle Tien Shan. In this regard, several magmatic pulses of high-potassic intrusions and corresponding metallogenic pulses can be suggested in this region. Whereas the early (ca. 337 to 315 Ma) igneous suites accompanied by dominantly porphyry Cu-Au-Mo mineralization, the later (ca. 305 to 285 Ma) suites including the Sonkul and Kokturpak plutons are accompanied by W- and/or Au-dominant mineralization. This mineralization appears to pre-date more substantial intrusion-related to orogenic-type Au mineralization. [ABSTRACT FROM AUTHOR]

The Waxing Mo polymetallic deposit is located in the central part of the Lesser Xing'an–Zhangguangcai Range (LXZR), NE China. The Mo (Cu) mineralization in the deposit is dominantly hosted by quartz veinlets and stockworks and is closely related to silicification and potassic alteration, while the W mineralization is most closely related to greisenization. Zircon samples from granodiorite, biotite monzogranite, granodiorite porphyry, and syenogranite in the Waxing deposit yielded U-Pb ages of 172.3 Ma, 172.8 Ma, 173.0 Ma, and 171.4 Ma, respectively. Six molybdenite samples from porphyry Mo ores yielded a Re-Os isochron age of 172.0 ± 1.1 Ma. The granitoids in the ore district are relatively high in total alkali (Na2O + K2O), are metaluminous to weakly peraluminous, and are classified as I-type granitoids. The zircon samples from all granitoids showed a relatively consistent Hf isotopic composition, as shown by positive εHf(t) values (3.1–8.3) and young TDM2 ages (0.69–1.25 Ga). These results, combined with the whole-rock geochemistry, suggest that the magma source of these rocks most likely derived from partial melting of a juvenile middle-lower continental crust, with a minor contribution from the mantle. These granitoids have compositional characteristics of adakites such as relatively high Sr contents (e.g., >400 ppm) and Sr/Y ratios (e.g., >33), as well as weak Eu anomalies (e.g., Eu/Eu* = 0.8–1.1), indicating extensive fractionation crystallization of a hydrous magma. The apatite geochemistry indicates that the ore-related magma in Waxing is F-rich and has a relatively low content of sulfur. The zircon geochemistry reveals that the granodiorite, biotite monzogranite, and granodiorite porphyry have relatively high oxygen fugacity (i.e., ΔFMQ = +1.1~1.3), whereas the fO2 values of the granite porphyry and syenogranite are relatively low (i.e., ΔFMQ = +0.1~0.5). The whole-rock and mineral geochemistry suggest that the Mo mineralization in Waxing is probably genetically related to granitoids (i.e., granodiorite, biotite monzogranite, and granodiorite porphyry), with higher oxygen fugacity and a high water content, whereas the magmatic S concentration is not the key factor controlling the mineralization. A comparison of the geochemical compositions of ore-forming and barren stocks for porphyry Mo deposits in the LXZR showed that geochemical ratios, including Eu/Eu* (>0.8), 10,000*(Eu/Eu*)/Y (>600), Sr/Y (>33), and V/Sc (>8), could be effective indicators in discriminating fertile granitoids for porphyry Mo deposits from barren ones in the region. [ABSTRACT FROM AUTHOR]

The Deki Amhare complex is located in central Eritrea, within the Arabian–Nubian Shield (ANS). It consists of an inner core of monzogranite porphyry and diorite enclaves (MMEs), surrounded outwardly by granodiorite and quartz diorite. The zircon U–Pb ages, whole-rock geochemistry, and Sr–Nd–Hf isotopic compositions of the Deki Amhare complex granitoids were used to discuss the Neoproterozoic tectonics of the ANS. The Late Tonian granodiorite and quartz diorite are metaluminous and calc-alkaline to slightly high-K calc-alkaline I-type plutons, with ages of 811.2 ± 4.8 Ma and 811.6 ± 5.7 Ma, respectively. They exhibit positive εHf(t) (7.6–9.5) and εNd(t) (3.9–4.7) values and relatively low (87Sr/86Sr)i ratios (0.70374–0.70463), indicating that they derived from the partial melting of a metasomatized mantle wedge during intra-oceanic subduction. The Ediacaran monzogranite porphyry and MMEs are subalkaline to alkaline A2-type granitoids with ages of 620.0 ± 4.3 Ma and 614.8 ± 3.9 Ma. These display positive εHf(t) (5.3–8.7) and εNd(t) (4.2–4.7) values, as well as low (87Sr/86Sr)i ratios (0.70310–0.70480), implying that they formed through crust–mantle magma mixing related to post-collisional slab break-off. Based on these data, three stages of regional tectonic evolution can be described: (1) from ~1200 Ma to ~875 Ma, the mafic oceanic crust was derived from depleted mantle during the opening of the Mozambique Ocean; (2) from ~875 Ma to ~630 Ma, intra-oceanic subduction and arc formation occurred with the development of I-type batholiths; and (3) from ~630 Ma to ~600 Ma, crustal and lithospheric reworking took place post-collision, leading to the formation of A2-type granitoids. [ABSTRACT FROM AUTHOR]

The newly discovered Oligocene granitoids (33.1–28.7 Ma) at Pagele are magmatic rocks related to beryllium mineralization during the India–Asia late‐collisional stage. This discovery provides an ideal example to study the late‐collisional orogeny and beryllium prospecting in the Lhasa terrane. The Oligocene granitoids include porphyritic granodiorite, Stage I, II and III granites, and granitic pegmatite. Geochemical analysis shows that the porphyritic granodiorite is characterized by high SiO2, K2O, total ΣREE contents, and (La/Yb)N ratios; while the latter two by higher SiO2, lower ΣREE and (La/Yb)N ratios. Notably, the granitic pegmatite has extremely high Y/Ho, low K/Rb and Zr/Hf, and distinct REE tetrad effect (1.14–1.21). This study suggests that the porphyritic granodiorite may be derived from partial melting of beryllium‐rich materials composed of Lhasa ancient crust (70%–80%) and enriched Lhasa lithospheric mantle (20%–30%) under the tearing subduction of Indian slab. The three‐stage granites and granitic pegmatite, which contain higher beryllium contents or beryls, were likely generated by highly fractionation of the porphyritic granodioritic magma or other homologous magma. Considering the possible genetic and spatial link between Indian slab tear and rifts, we suggest that highly‐fractionated granites in rifting systems represent important Be prospecting targets in the Lhasa terrane. [ABSTRACT FROM AUTHOR]

Laozuoshan Gold Deposit is a large-scale gold deposit located in Northeast China, within the central part of the Jiamusi Block in the eastern section of the Khingan-Mongolia orogenic belt. This area represents a complex tectonic zone, influenced by the subduction and transitions of the Paleo-Asian Ocean, the Mongolia-Okhotsk Ocean, and the Paleo-Pacific Ocean. To explore the nature and composition of the ore-forming fluids and the sources of metallogenic materials, systematic studies on C-H-O isotopes from ore-forming fluid inclusions and S-Pb isotopes from ore minerals were conducted. Results show that δ13CPDB values range from 3. 932 ‰ to 5. 390 ‰, δ18OH2O from 2. 17 ‰ to 5. 60 ‰, and δD from-90. 482 ‰ to -90. 569 ‰, indicating that the ore-forming fluids are primarily derived from deep magmatic sources, with meteoric water mixing during the late mineralization stage and partial interaction with the carbonaceous rock units of the Mashan Group. Sulfides from the ore bodies have δ34S values ranging from 3. 3 ‰ to 5.1‰, sulfides from the mineralized alteration zones have δ34S values between 3. 9 ‰ and 5. 3 ‰, and sulfides from the mixed rocks and granites range from 3. 5 ‰ to 5. 2 ‰, suggesting that the ore-forming fluids were relatively weakly reducing. The Pb isotopic ratios of ore minerals are 206Pb/204Pb=18. 165-18. 571, 207Pb/204Pb=15. 452-15. 613, and 208Pb/204Pb=37. 764-38. 396, while magmatic rocks have 206Pb/204Pb=18. 151-18. 655, 207Pb/204Pb=15. 526-15. 634, and 208Pb/204Pb=37. 855-38. 050, indicating that the ore bodies and the magmatic rocks share a common origin, with ore-forming materials sourced from magmatic rocks. Given that the granodiorite closely associated with mineralization is the product of partial melting of the lower crust, it is further inferred that the ore-forming materials are crust-derived. Based on the geological characteristics of the deposit, it is concluded that Laozuoshan Gold Deposit is a weakly reducing skarn-type gold deposit. [ABSTRACT FROM AUTHOR]

Buziwannan granodiorite and monzogranite associated with gold–polymetallic mineralization are located in the West Kunlun Orogen Belt in northwest China. Granodiorite was emplaced earlier than monzogranite. To determine the genesis of plagioclase from two intrusions and their relation with mineralization, the major, trace elemental, and Sr isotopic compositions of plagioclase were determined through LA-ICP-MS and LA-MC-ICP-MS respectively. The results indicated that the plagioclase from granodiorite had a high-An (around 40%) core and low-An (around 33%) rim, while the plagioclase from monzogranite was uniform with an An value around 18%. The (87Sr/86Sr)i ratios of plagioclase decreased with decreasing An value, which may be caused by small-scale crustal contamination and/or magma mixing. The crystallization process of plagioclase is mainly accompanied by the exsolution of magmatic H2O, and the pressure changes caused by the loss of magma H2O. These magmatic fluids are rich in ore-forming elements, such as Au–Ag–Cu–Zn, and form skarn mineralization near the wall rocks. Because of the co-crystallization of plagioclase, hornblende, and biotite, as well as the addition of minor felsic magma with lower Sr isotopic composition, the plagioclase from monzogranite exhibits low and uniform An values. In addition, a large amount of magmatic H2O carrying ore-forming elements was released during the emplacement of granodiorite, which caused the monzogranite to lose its metallogenic potential. [ABSTRACT FROM AUTHOR]

A combined study of whole-rock geochemical and Sr-Nd isotopic data, and zircon U-Pb geochronological and Hf isotopes has been carried out for several Neoproterozoic intrusions, including the Lung Thang, Posen and Sin Quyen in the Phan Si Pan Zone, northwest Vietnam to constrain their age, petrogenesis and tectonic implications. The Lung Thang and Posen intrusions, mainly composed of granodiorite, were formed at 803–777 Ma and are characterized by moderate SiO2 (64.43–66.65 wt.%), and K2O (4.05–4.89 wt.%), with A/CNK and A/NK values of (0.94–1.03) and (1.72–2.11), respectively. They have negative whole-rock εNd(t) (−6.16 to −3.73) and zircon εHf(t) values (−7.9 to −4.1), which suggest that the Lung Thang and Posen intrusions were generated by partial melting of ancient, K-rich crustal rocks. The Sin Quyen intrusion, occurring as dykes, is composed of monzodiorite and was emplaced at 742 ± 3 Ma. The Sin Quyen intrusion has high alkalies (K2O+Na2O = 7.42–7.47 wt.%), and low MgO (<1.31 wt.%) and Ni (6.55–6.93 ppm), with A/CNK and A/NK values of (0.67–0.68) and (1.64–1.68), respectively. Their whole-rock εNd(t) and zircon εHf(t) values are −6.15 to −5.92 and −5.8 to + 8, respectively. These geochemical characteristics suggest that the Sin Quyen intrusion was produced by the partial melting of ancient crustal sources mingled with mantle-derived components. Geochemically, the Lung Thang, Posen and Sin Quyen intrusions are medium- to high-K, calc-alkaline in nature and show enrichment in LILE (Th, U, K, Rb) and LREE, and strong negative anomalies of Nb, Ta, and Ti. Such geochemical characteristics suggest that they formed in a subduction-related tectonic environment. The geochronological and geochemical correlation of these intrusions with those along the southwestern margin of the Yangtze Block in South China suggests that the Phan Si Pan zone in northwestern Vietnam is a constituent of the SW Yangtze Block. Additionally, these intrusions show a significant correlation with other contemporaneous magmatic rocks in the northeast Indochina Block, Lhasa Block, the northwestern margin of Greater India as well as those in Seychelles and northern Madagascar. This correlation suggests a similar history and synchronous episode of crustal growth/recycling in an Andean-type arc system along the western and northern margin of the Rodinia supercontinent during the Neoproterozoic. [ABSTRACT FROM AUTHOR]

The Heijianshan granodiorite is located in the Xiao Requanzi-Dananhu Paleozoic residual arc of the Late Paleozoic arcbasin system in the eastern Tianshan orogenic belt. Clues from fieldwork, petrography, geochemistry and Zircon U-Pb geochronology were integrated to provide constraints on the tectonic setting in the Late Devonian. Geochemistry data shows that the granitic amphibolite is a set of type I granite with the characteristics of high silica, quasi-aluminous, and medium-high potassium-calcium alkalinity. The total amount of rare earth elements varies from 112. 82 × 10 - 6 to 129. 91 × 10 - 6, and the light / heavy rare earth ratio varies from 8. 73 to 11. 26 (mean value 9. 64). Eu elements show weakly negative anomalies (δEu = 0. 77 ~ 0. 85). The sample is enriched in large ion lithophile element (LILE, e. g., Rb, Ba,K, U), lacking high-field strength elements (HFSE, e. g., Ta, Nb, and Ti) and P, with significant negative anomalies in Nb and Ta. It shows the characteristics of island arc magmatic rocks. The inductively coupled plasma mass spectrometry(LA-ICP-MS) zircon U-Pb isotope dating results show that the weighted average ages of granitic amphibolites in the area are (373. 0 ± 3. 0) Ma, indicating that the granodiorites were formed during the Late Devonian, and are contemporaneous products of large-scale Late Paleozoic medium-acidic magmatic intrusion in the Xiao Requanzi-Da Nanhu island arc of the east Tianshan Block. The combination of regional geological features, petrography and magma source area characteristics suggests that the Late Devonian granodiorite in the Heijinshan area of the east Tianshan block is a product of the island-arc of the northward subduction of the ancient oceanic plate [ABSTRACT FROM AUTHOR]

In recent years, the volcanic–plutonic relationship has been a contentious topic among researchers. Based on this issue, they have delved deeper into the constraints of magma reservoir pressure and H2O on pre-eruptive melt accumulation and migration. We selected granodiorite, tonalite, and rhyolite in the Dehailonggang volcanic–plutonic complex to investigate the volcanic–plutonic connection and constraints of reservoir pressure and H2O on the pre-eruptive melt accumulation and migration in water-rich systems. Granodiorite, tonalite, and rhyolite exhibit temporal–spatial similarities (247 Ma) and the same magmatic origin consisting of ca. 75–80% enriched mantle materials mixed with ca. 20–25% lower crustal materials. TESCAN integrated mineral analyzer (TIMA) shows that both granodiorite and tonalite display a typical cumulate texture. The bulk–rock compositional complementary of the granodiorite, tonalite, and rhyolite, coupled with in situ geochemical signatures of feldspars and zircons, feldspar CSD, and rhyolite–MELTS modeling, indicate that (1) the granodiorite represents the crystal cumulate formed after crystal–melt phase separation of the original mush (OM) in the magma reservoir; (2) the interstitial melt of the OM was extracted, migrated, and ultimately erupted as the rhyolite; (3) the tonalite serves as an intermediate product resulting from the phase separation from the OM to the rhyolite. Rhyolite–MELTS modeling reveals that in water-rich environments, an increase in reservoir pressure (prior to reaching overpressure threshold) can lead to a reduction in melt viscosity. This, in turn, accelerates mechanical compaction and phase separation processes, ultimately shortening the pre-eruptive melt aggregation timescale. In contrast, it is noteworthy that H2O has a relatively minor influence on phase separation in such water-rich systems (> 4 wt. %). This study demonstrates the volcanic–plutonic genetic coupling and highlights the significance of reservoir pressure in controlling the dynamics of pre-eruptive melt within water-rich systems. [ABSTRACT FROM AUTHOR]

Mesozoic granitoid formations offer crucial insights into the tectonic history of the North China Craton. New zircon U-Pb ages of two Mesozoic granitoids in the Huai'an terrane yield ages of 226.4 ± 1.1 Ma for the Yihe (YH) granite and 156.3 ± 2.9 Ma for the Zhujiagou (ZJG) granodiorite. The negative Nb, Ta, and Ti anomalies; high Nb/Ta ratios (20.4 to 24.1); high (La/Yb)N (30–84); low initial 87Sr/86Sr ratios (0.707725–0.708188); and negative ƐNd(t) values of the Yihe complex suggest that it originated from the partial melting of the lower crust and lithospheric mantle. However, the geochemical and Sr-Nd isotopic results of the ZJG granodiorite are characterized by I-type granites: Na2O + K2O values of 7.27 to 7.94 wt%, negative Nb anomalies, positive Pb anomalies, higher initial 87Sr/86Sr ratios (0.710979–0.714841), and much lower ƐNd(t) values (−27.1 to −30.1). The Late Jurassic Zhujiagou complex was derived from partial melting of a thickened low crust, and during the Late Triassic, magmatic rocks were formed under a post-collisional extensional regime. Multiple upwellings of the asthenosphere facilitated the mixing of magmas derived from partial melting of the lithospheric mantle and lower crust. These mixed magmas then ascended to the upper crust after undergoing fractional crystallization, leading to the formation of the YH complex. In the Late Jurassic, the tectonic regime of the NCC shifted from compression to extension. The Late Jurassic intrusion identified in this study developed within a compressional setting linked to the subduction of the Paleo-Pacific Ocean. [ABSTRACT FROM AUTHOR]

The Baoshan Cu-Pb-Zn deposit is situated at the intersection of the Qin-Hang Cu polymetallic and Nanling W-Sn polymetallic metallogenic belts. The age, lithology, petrogenesis, and tectonic setting of granodiorite porphyry within the deposit remain subjects of debate. Additionally, there is a lack of comparative studies with the W-Sn-related granites in the region. This study conducted whole-rock major and trace element analysis, Sr-Nd isotope analysis, and zircon U-Pb dating on the Baoshan granodiorite porphyry. The zircon U-Pb age of the granodiorite porphyry is 162 ± 1 Ma. The whole-rock SiO2 and K2O contents range from 65.87 to 68.21 wt.% and 3.42 to 5.62 wt.%, respectively, indicating that the granodiorite porphyry belongs to high-potassium calc-alkaline I-type granite. The granodiorite porphyry is characterized by enrichment in LREE and depletion in HREE (LREE/HREE ratio = 6.2–21.2). The samples of granodiorite porphyry generally exhibit weak negative Eu anomalies or no Eu anomalies (δEu = 0.62–1.04, mean = 0.82). The (87Sr/86Sr)i and εNd(t) values are 0.707717–0.709506 and −7.54 to −4.87, respectively. The whole-rock geochemical composition and Sr-Nd isotopic values indicate that the magma originated from the partial melting of the Mesoproterozoic ancient crust and Neoproterozoic mafic juvenile lower crust, with the addition of high oxygen fugacity and water-rich lithospheric mantle melts. The source of the granodiorite porphyry in the Baoshan deposit is significantly different from the crust-derived metapelite source of the W-Sn-related granite in the area, indicating that different magma sources might be the main reason for the co-spatial and nearly contemporaneous development of Cu-Pb-Zn and W-Sn mineralization in the southern Hunan region. [ABSTRACT FROM AUTHOR]

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In this study, the effect of using waste granodiorite powder (WGP) as a cement replacement material in percentages ranging from 1 to 9% on various physical and mechanical properties of ordinary concrete was investigated. The resistance of produced concretes with WGP to the high temperature effects on the 28 days compressive strength were studied as well. Granodiorite is one of the well-known igneous rocks that have been used in previous research as a replacement for coarse or fine aggregates due to the hardness of its grains. However, rare studies have investigated its powder as a partial cement replacement material. Results showed the ability of investigated WGP with high surface area to act as a supplementary cementitious material that contributed to enhance the results of mechanical and physical properties of concrete. At traditional room temperature, the optimal replacement percentage was 7%, where the 28 days compressive and tensile strengths were improved by 28.3% and 17.3%, respectively. The optimal replacement ratio varied between 7 and 9% in the case of high temperatures, according to exposure time and temperature degree. Statistical and sensitivity analysis was conducted on 66 available compressive strength value represents all variables before and after elevated temperature exposure. While the regression equation showed good R2 value of 85.3%, sensitivity analysis indicated that compressive strength value is most sensitive to temperature, followed by WGP ratio and exposure time, with importance values of 56, 26, and 18 %, respectively. Results showed also that the setting times and consistency was decreased with increasing the replacement ratio with WGP, while the workability was slightly improved up to 5% replacement ratio. Furthermore, microstructure analysis showed that WGP can help to densify the concrete matrix due to its small size and ability to fill the interstitial voids in the concrete matrix. [ABSTRACT FROM AUTHOR]

The Aruhan granodiorite intrusion in Xiwuqi, Inner Mongolia, is exposed along the central and eastern parts of the Hegenshan suture zone. LA-ICP-MS zircon U-Pb dating shows that the ages of the granodiorite are ranging from 332±3 to 327 ±1 Ma, suggesting emplacement during the Early Carboniferous. The Aruhan granodiorite is characterized by high contents of SiO2 (65.20% to 68.27%), Al2O3 (15.61% to 17.35%), Sr (472x10-6 to 552x10-6) and low contents of MgO (1.16% to 1.61%), Yb (0.86x10-6 to 1.13x10-6), Y (7.29x10-6 to 11.42x10-6, with Na2O/K2O and Sr/Y ratios ranging from 2.56 to 4.35 and 43.45 to 75.68, respectively. The total REE is low (44.73x10-6 to 88.11x10-6), the fractionation of REE is significant [(La/Yb)N = 6.65 ~ 13.85], and the anomaly of Eu (δEu = 0.79 to 1.07) is not obvious. The geochemical characteristics of the whole-rock indicate that the Aruhan granodiorite belongs to typical high-SiO2 island arc adakites (O-type) series, formed in an environment of active continental marginal arc. The source of the maga might be the product of partial melting of subducting oceanic crust with oceanic sediments, which reacts with overlying mantle peridotite. Crystallization differentiation and contamination by crustal materials might occurre during its emplacement. This discovery may support the fact that the central and eastern parts of the Hegenshan Ocean was not yet closed during the Early Car-boniferous. Combined with the regional research, we preliminarily believe that the Hegenshan Ocean may have undergone bidirectional subduction and abatement during the Early Carboniferous, which is different from the previous view that the Hegenshan Ocean underwent unidirectional subduction and abatement northward only. [ABSTRACT FROM AUTHOR]

In this paper, an assessment of the natural radioactivity level, radon exhalation, metal contamination, and mineralogy of a granodiorite rock sample from Stilo, in the Calabria region, Southern Italy is presented as a case study. This rock was employed as a building material in the area under study. The specific activity of 226Ra, 232Th and 40K natural radioisotopes was assessed through high-purity germanium (HPGe) gamma-ray spectrometry. Then, several indices such as the absorbed gamma dose rate (D), the annual effective dose equivalent (AEDE), the activity concentration index (ACI) and the alpha index (Iα), were quantified to determine any potential radiological health risk related to radiation exposure from the analyzed rock. Furthermore, E-PERM electret ion chambers and inductively coupled plasma mass spectrometry (ICP-MS) measurements were carried out to properly quantify the radon exhalation rate and any possible metal pollution, respectively. In particular, to further address metal pollution factors, the geo-accumulation index (Igeo) was calculated to properly address the toxicity levels of the ecosystem originating from the detected metals. Finally, with the aim of successfully discriminating the provenance of such naturally occurring radionuclides, a combined approach involving X-ray diffraction (XRD) and µ-Raman spectroscopy was employed for the identification of the main radioisotope-bearing minerals characterizing the investigated granodiorite. The results achieved in this case study can be taken as the basis for further inquiries into background levels of radioactivity and chemical contamination in natural stone employed as building materials. [ABSTRACT FROM AUTHOR]

Although considered a crucial component of the Rodinia supercontinent, it remains uncertain how the Yangtze craton relates to the accretion and breakup of Rodinia. Here, the Huanglingmiao granitic complex (HGC), an intermediate-acid rock series that intruded on the southern Kongling terrane of the northern Yangtze craton margin, is investigated to help resolve this conundrum. Our analysis indicates that these rocks consist of tonalite, trondhjemite, granodiorite, oligoporphyritic granodiorite, porphyric biotite granodiorite, and fine- to medium-grained granodiorite dyke compositions. Collectively, this assemblage is further subdivided into two categories by their temporal, spatial, and geochemical features into early TTG-like and later granitic–dioritic units, which are composed of tonalite, trondhjemite, granodiorite, porphyritic granodiorite, and the fine- to medium-grained granodiorite dykes, respectively. Zircon U-Pb dating yields ages of 865~850 Ma for the TTG-like rocks, 844~825 Ma for the porphyritic granodiorites, and ~800 Ma for the granodiorite dykes. Combined with geochemical evidence, the data suggest that the early- and late-series rocks were formed by a partial melting of Mesoproterozoic and Paleoproterozoic crustal materials, respectively, suggesting that the vertical layering of the crust controlled the composition of the independent units. In addition, isotopic evidence points to different sources for the various rocks in the Kongling terrane and that mantle-derived materials influenced the early-series lithologies. Combined with previous studies on the northern margin of the Yangtze craton, it is inferred that the early-series rocks formed in an active continental margin environment, while the late-series rocks display within-plate boundary formation characteristics. The multiple magmatic activities revealed by this study record sequential partial melting with tectonic transition characteristics from an Andean-type to within-plate magmatism in the northern margin of the Yangtze craton. Taken together, these observations point to a strong association between these rocks, convergence, and incorporation of the northern Yangtze craton margin into the Rodinia supercontinent during the Tonian Period. [ABSTRACT FROM AUTHOR]

The Osumi Granodiorite, located on the Osumi Peninsula in southwest Japan, is an example of outer zone granites that were formed during a limited period (13–15 Ma) in response to the subduction of the Philippine Sea Plate. This event, which is linked to the separation of southwest Japan from continental Asia, resulted in unique igneous activity. The Osumi Granodiorite is the largest Miocene granite body in the region. It intrudes into the Mesozoic to Paleogene accretionary complex of the Shimanto Belt and affects contact metamorphism. Despite considerable research on the Osumi Granodiorite, limited geochemical studies, especially on trace and rare earth element (REE) analyses, have been conducted. Furthermore, there are insufficient data on the Rb–Sr isotopic system, leaving the formation process unclear. This study presents whole-rock geochemical and Rb-Sr isotopic data to investigate the petrogenesis of the Osumi Granodiorite. The results suggest a common magma origin for this pluton, as indicated by linear trends on the Harker diagrams and similar REE patterns. The presence of a relatively large Eu anomaly implies formation under a reducing environment. The AKF diagram indicates predominant contamination by pelitic rocks of the Shimanto Belt during magma formation. The Rb–Sr whole-rock isochron diagram and SrI–1000/Sr diagram suggest that the Osumi Granodiorite body was formed by heterogeneous assimilation of magma into the Shimanto Belt. Furthermore, the whole-rock isochron age is 64.3 Ma, which differs by approximately 50 My from the previously reported biotite K–Ar age (14–22 Ma). This age is considered to be a pseudo-isochron age, rather than the consolidation age. During the middle Miocene, the compressive stress field in the outer zone south of the Butsuzo Tectonic Line made it difficult for magma to rise. As a result, it reacted with the sedimentary rocks of the Shimanto Belt to various degrees. The Osumi Granodiorite underwent magma differentiation upon intrusion into the Shimanto Belt. It subsequently ascended, cooled, and interacted with pelitic rocks under stable geological conditions. [ABSTRACT FROM AUTHOR]

This study investigates the individual and combined effects of micro and nano lead monoxide (PbO) and granodiorite (GD) on concrete's mechanical and radiation shielding properties. Both materials were partially substituted for cement at varying ratios. Additionally, mixtures with optimal radiation shielding performance were prepared to explore the synergy of combining them. The mentioned materials are used for the first time in an extensive study at the nano scale to investigate their impact on concrete's mechanical properties, microstructure, and gamma radiation attenuation. Two gamma ray sources of uranium (U238) and cesium (Cs137) were used measure the radiation attenuation coefficients for all designed concrete mixes. A simple methodology was followed to assess the concrete shields efficiency via utilizing portable handheld gamma‐ray spectrometer that offers two reading modes. Results indicated that increasing the ratio of PbO is directly proportional to the concrete ability to attenuate radiation, where the optimal individual replacement ratios were recorded at 5% for micro and nano particle sizes. At this ratio, the linear attenuation coefficient (μ) values were improved by 39.57% and 24.78% for the nano and micro PbO, respectively. Additionally, the optimal ratio for improving mechanical properties was at 3% and 2% for nano and micro PbO, while the higher ratios showed a decline in mechanical properties especially at 5% micro PbO with 7.02% reduction in the compressive strength value. Regarding GD powder, the optimal replacement ratios for improving concrete radiation shielding were consistent with those enhancing its mechanical properties at 4% and 7% in both nano and micro scales, respectively. The combined mixes further enhanced the overall concrete performance, especially its radiation shielding ability. Compared to the control mix, the compressive strength, tensile strength, and μ were increased by 25.7%, 16.2%, and 44.7% at the optimal mixture of 5% nano PbO + 4% nano GD. [ABSTRACT FROM AUTHOR]

Cooling techniques following thermal treatments and related microcracking are a hot spot in rock mechanics and must be precisely studied. Hence, this research performed systematic experiments on the influences of rapid cooling on the behavior of thermally treated granodiorite at different temperatures. Furthermore, using the optical microscope, a comparison between rapid and slow cooling methods was studied to investigate how the cooling process affected the microstructure of the Egyptian granodiorite. The granodiorite samples were heated to 200, 400, 600, and 800 °C and then cooled slowly by air and rapidly by the water. According to the experimental results, the changes in examined properties occurred in three distinct temperature stages: zone I (25–200 °C), zone II (200–400 °C), and zone III (400–800 °C). Zone II was a conspicuous transition region for the rapid cooling approach, distinguished by a significant increase in porosity, thermal damage, crack density, and a substantial decrease in wave velocities, uniaxial compressive strength, and elastic modulus. Microcrack densities and widths increased with temperature for both cooling methods. According to microscopic analyses of granodiorite samples, boundary cracks were formed at the boundaries of quartz and feldspar first due to their minimal lattice energy, followed by biotite of high lattice energy. However, due to the thermal shock induced, the intragranular microcracks of the rapid cooling technique began to form at lower temperatures (200 °C). The physical and mechanical properties of rapidly cooled granodiorite significantly dropped between 200 and 400 °C, and the failure mode altered from axial splitting to shear modes. Consequently, over 600 °C, longitudinal waves could not penetrate rock samples due to the thermal fusion of inter and transgranular fissures, which turned into macrocracks. Hence, the elastic modulus measurements and wave velocity at 800 °C were challenging with an extremely low UCS and complex failure mode. [ABSTRACT FROM AUTHOR]

The paper studies the geochronology and geochemistry of Qinjialing granodiorite and Hongqiling quartz diorite in Xiuyan-Fengcheng area, eastern Liaoning Province. The LA-ICP-MS zircon U-Pb dating yields the weighted average ages of 1 27.5±0.9 Ma for Qinjialing granodiorite and 1 26.5±0.8 Ma for Hongqiling quartz diorite, both of which were formed in the Early Cretaceous. The lithogeochemical analysis results show that the content of SiO2 in Qinjialling granodiorite is 70.40%-72.28%, with the A/CNK and ANK values of 0.99-1.06 and 1.44-1.61, respectively. The granodiorite is characterized by relatively enriched LREEs, depleted LILEs (Ba and Sr) and HFSEs (Nb, P and Ti), and enriched Rb, Th, La, Nd, and Hf, with the zircon saturation temperature ranging from 755 °C to 8 1 6 °C, belonging to peraluminous I-type granite, formed by the partial melting of lower crust. The content of SiO2 in Hongqiling quartz diorite is 56.42%-57.22%, with the ACNK and ANK values of 1.04-1.09 and 1.70-1.83, respectively. The quartz diorite is characterized by obvious negative Eu anomaly, depleted Sr, Nb, Ta, Ti and P, and enriched Ba, Rb, K, Zr, Hf and Th. The source material is derived from the crust with minors of mantle-derived component. The Qinjialing granodiorite and Hongqiling quartz diorite were formed in the Early Cretaceous extensional environment of eastern Liaoning, which are closely related to the destruction of North China Craton and lithospheric thinning. [ABSTRACT FROM AUTHOR]

Pressure–temperature estimates of a xenolith found within a post-obduction granodiorite in southern New Caledonia provide evidence for subcrustal, granulite facies, peak crystallisation conditions (ca. 850 °C—8.5 ± 1.0 kbar), followed by isobaric cooling to 700 °C, and final decompression with partial rehydration at ca. 650 °C—3.5 kbar. The xenolith, dated at 24.7 Ma (U-Pb zircon), i.e., the same age as the granodiorite host rock, has low SiO2 (35.5 wt%) and high Al2O3 (33.2 wt%) contents, suggesting that it is the restite of a previous melting episode, while the elevated Ca (Ba and Sr) contents suggest mantle metasomatism. Although the concentrations of Rb, K, Ca, Ba, and Sr have been strongly modified, some geochemical (REE patterns and some "immobile" trace element ratios) and isotopic (Sr and Nd isotopic ratios, U-Pb zircon age) characteristics of the granulite facies xenolith are similar to those of the xenoliths found in other Late Oligocene intrusions in southern New Caledonia; therefore, this rock is interpreted to be related to an early magmatic episode. The rock protolith was emplaced and equilibrated at the base of the crust where it underwent ductile deformation. Younger ascending magma picked it up and they eventually crystallised together at a shallow crustal level, near the tectonic sole of the ophiolite. The recrystallisation and ductile deformation at ~8.5 kbar suggest that a rheological discontinuity existed at about 25–28 km, probably representing the Moho. It is concluded that a continental crust of normal thickness must have existed beneath New Caledonia at about 24 Ma, i.e., 10 Ma after obduction. [ABSTRACT FROM AUTHOR]

Mineral transformations often induce microstructural deteriorations during temperature variations. Hence, it is crucial to understand why and how this microstructure weakens due to mineral alteration with temperature and the correlated physical and mechanical responses. Therefore, in this study, physical, chemical, thermal, petrographic, and mechanical analyses were carried out to comprehend better the thermal behaviors of Egyptian granodiorite exposed to temperatures as high as 800 °C. The experimental results indicate that the examined attributes change in three distinct temperature phases. Strength zone (up to 200 °C): During this phase, the temperature only slightly impacts the granodiorite mass loss and porosity, and the P-wave velocity and E slightly decrease. However, the rock structure was densified, which resulted in a minor increase in strength. After that, the transition zone (200–400 °C) was distinguished by the stability of most studied parameters. For instance, mass and porosity did not significantly alter, and the uniaxial compressive strength steadily increased with an axial failure mode. When the temperature rises, transgranular cracks cause the P-wave velocity and elastic modulus to decrease moderately. The decay zone started after 400 °C and continued to 800 °C. This zone is characterized by complicated factors that worsen the granodiorite properties, lead to color shift, and produce a shear failure mode. The properties of granodiorite became worse because of chemical reactions, structural and crystal water evaporation, rising thermal expansion coefficient variation, and quartz inversion at 575 °C (α to β, according to the differential thermal analysis). Thermal damage greatly affected granodiorite's physical and mechanical properties and microstructure at 800 °C. As a result, UCS measurements were extremely small with a complex failure pattern, making Vp and E unattainable. [ABSTRACT FROM AUTHOR]

The Bam area is located north of the Kerman magmatic copper belt (KMCB) in SE Iran. It belongs to the Urumieh-Dothtar magmatic assemblage (UDMA) that hosts many large Cu-porphyry deposits such as Sarchemeh, Iju, Meiduk, Pakram, and Dalli. The area comprises volcanic and volcano-sedimentary rocks of the Eocene intruded by some sub-volcanic patches. Geochemical analyses show that the sub-volcanic rocks are calc-alkaline granodiorites formed on an active continental margin. The rare earth elements (REE) distribution patterns are differentiated (LaN/YbN = 4–31), having weak to moderate Eu negative anomalies (Eu/Eu* = 0.4–0.8) and flat heavy rare earth element (HREE) sections. The MgO, SiO2, La, Yb, Sr, Sm, and Y contents of these rocks are consistent with adakite-like magmas formed by partial melting of thickened lower crust containing no garnet. Negative correlations of Al2O3, Y and Ba with SiO2 and moderate to weak Eu negative anomalies, indicate the role of hornblende, K-feldspar, and plagioclase fractionation in the formation of these rocks. Geochemical features of the Bam sub-volcanic rocks are similar to those of the Cu-porphyry deposits from UDMA and Malmyzh deposit from eastern Russia, indicating fertility of these rocks for Cu mineralization that should be considered in the future explorations. [ABSTRACT FROM AUTHOR]

A reconnaissance study of the Ash-Sharqi area displays that this area is covered by Tertiary rift-related volcanic rocks and their associated plutonic rocks with some exposures of Mesozoic sandstones. These volcanic rocks belong to the Yemen Trap Series (YTS) that form the lower part of the Yemen Volcanic Group (YVG), which consists of a part of the Afro-Arabian continental flood basalt province. The plutonic rocks are represented by intrusion composed of granitoid rocks located in the center of the study area, which is the subject of this paper. These granitoid rocks range in composition from granite (G) to quartz-monzonite - quartz-monzodiorite - quartz diorite (QM-QMD-QD) and are composed of plagioclase (An32-46: Andesine), K-feldspars, quartz, hornblende with minor, biotite, opaques, allanite and zircon. Secondary minerals are represented by chlorite, sericite calcite sphene, hematite epidote, and kaolinite. These rocks show variations in their colors (color index 6 to 47 vol. %) and grain sizes, which reflect changes in mineral composition and textures. They have equigranular, porphyritic, rapakivi, and anti-rapakivi textures and contain enclaves of various sizes of basalt and diorite blocks. Xenocrysts of pyroxene and plagioclase are found and detonated during the magma-mingling processes. Finally, these granitoid rocks are subjected to various degrees of hydrothermal alterations, including silicification, argillization, hematitization, chloritization, epidotization, sericitization, carbonation and spheronization. [ABSTRACT FROM AUTHOR]

Geodynamic mechanism responsible for the generation of Silurian granitoids and the tectonic evolution of the Qilian orogenic belt remains controversial. In this study, we report the results of zircon U–Pb age, and systematic whole-rock geochemical data for the Haoquangou and Liujiaxia granitoids within the North Qilian orogenic belt and the Qilian Block, respectively, to constrain their petrogenesis, and the Silurian tectonic evolution of the Qilian orogenic belt. Zircon U–Pb ages indicate that the Haoquangou and Liujiaxia intrusions were emplaced at 423 ± 3 Ma and 432 ± 4 Ma, respectively. The Haoquangou granodiorites are calc-alkaline, while the Liujiaxia granites belong to the high-K calc-alkaline series. Both are peraluminous in composition and have relatively depleted Nd isotopic [εNd(t) = (− 3.9 – + 0.6)] characteristics compared with regional basement rocks, implying their derivation from a juvenile lower crust. They show adakitic geochemical characteristics and were generated by partial melting of thickened lower continental crust. Post-collisional extensional regime related to lithospheric delamination was the most likely geodynamic mechanism for the generation of the Haoquangou granodiorite, while the Liujiaxia granites were generated in a compressive setting during continental collision between the Qaidam and Qilian blocks. [ABSTRACT FROM AUTHOR]

The present work illustrates the structural setting in the Hamadat core complex, which located in the Midyan terrane. It is essential to understand deformational processes and products at different scales, which depend on the calculation of finite strain. To assess the tectonic development and structures in the Hamadat core complex, we use field investigation, finite strain analysis and microstructural examination. The Hamadat core complex employed the Rf/φ and Fry techniques for feldspar and mafic grains with 24 collected samples for gneisses, metavolcano-sedimentary rocks from both the Zaam and Baydah groups, deformed granodiorite for Jar-Salajah intrusion and Qazzaz granite. According to finite-strain data, the various rock units have moderate to high degree of deformation, and the axial ratios for XZ section vary from 1.80 to 4.50 for the Rf/φ technique and from 2.10 to 7.40 for the Fry technique. It concluded that the shortening axes display the subvertical related to the subhorizontal foliation. The strain data have the same main-phase foliation and similar deformation behavior. Finite strain acquired through high pressure metamorphism in this instance suggested that the contacts of nappe developed through the buildup of ductile strains. Also, during thrusting and intrusions throughout the deformation process, a building of brittle to ductile deformation was mostly caused by pure shearing in the study area. [ABSTRACT FROM AUTHOR]

LA-ICP-MS zircon U-Pb age of the Middle Jurassic granodiorite is 172. 7±1. 1 Ma in Gaxiangou area, northern Great Xing'an Range. The whole-rock SiO2 content ranges from 62. 81% to 68. 78% with higher whole-alkali (ALK) and Al2O3 and lower FeOT, MgO and TiO2 tontents. Rittman index (σ) is from 2. 27 to 5. 33, Na2O/K2O = 1. 19-3. 57, Mg# values from 38. 0 to 49. 0, aluminum saturation index (A/CNK) = 0. 91-0. 97, illustrating the granodiorite belongs to medium-high potassium calc-alkaline series and metaluminous rocks. The ∑REE = (117. 70-146. 32) × 10-6, and (La/Yb)N = 11. 70-18. 10, show a right-leaning distribution pattern with enrichment in light rare earth elements and relative depletion in heavy rare earth elements. Slightly Eu negative anomaly (δEu = 0. 86 - 0. 98) suggests that there is no significant plagioclase remains or fractional crystallization in the source region. The high Zr/Hf, Nb/Ta and Sr/Y ratios, low Y and Yb contents, enrichment of the large ionic lithophilic elements Rb, Sr and Ba, and depletion of the high-field-strength elements Nb, Ta and Ti indicate that the source rocks are crust-derived. P2O5 decreases with increasing SiO2 content and TZr values range from 700. 50 to 781. 20 °C. These indicate that the diagenetic type of this granodiorite is an I-type granite with C-type edakite characteristics. Combined with the regional data, the Middle Jurassic granodiorites were formed in the transition from collision to post-collision, and the Mongolian-Okhotsk Ocean tectonic system in the Middle Jurassic was characterized by a tectonic regime shift from extrusion to extension, and from crustal thickening to thinning, which is corresponding to the significant decrease of magmatic activity in the Middle Jurassic. [ABSTRACT FROM AUTHOR]

The newly identified Neoproterozoic Yuanmou high-Nb mafic and adakitic rocks at the western margin of the Yangtze Block in South China are investigated for petrogenesis and geodynamic implications. Zircon U-Pb ages show the adakitic granodiorite host and mafic microgranular enclaves (MMEs) were synchronously emplaced at 811-806 Ma, and were cut by an 802 ± 11.5 Ma mafic dike. The medium-grained granodiorites consist mainly of plagioclase, quartz, K-felspar, biotite, and amphibole. High SiO2 (62.8-67.5 wt%), Al2O3 (13.1-16.8 wt%) contents, high Sr/Y (17.4-49.0), and (La/Yb)N (16.3-52.6) but low Y (6.83-16.1 ppm) and Yb (0.74-1.82 ppm) concentrations of the granodiorites point toward their calc-alkaline and adakitic nature. Further, their high Dy/Yb (1.52-2.31) and Gd/Y (2.35-4.43) and low K2O/Na2O (0.22-0.48) and Th/La (0.14-0.20) ratios, constant bulk rock εNd(t) (-0.5 to -1.5) and zircon εHf(t) (0.0 to +2.3) values, suggest that the granodiorites were derived from partial melting of a mafic lower crustal source. The MMEs in the granodiorites and mafic dike intrusions are composed of amphibole, plagioclase, clinopyroxene, and olivine, and have similar chemical compositions, such as high Nb (15.7-41.9 ppm) and TiO2 (2.13-3.39 wt%) contents and high Nb/U (18.7-30.9) values, akin to alkaline high-Nb basalts (HNB). Their variable Ba/Nb (7.68-79.2), Nb/Zr (0.09-0.16), high Nb/Th (5.47-6.68), and low Th/Zr (0.01-0.03) and La/Nb (1.03-1.37) ratios indicate a mantle source modified by melts derived from subducted oceanic crust and sediments. The Yuanmou HNB with high εNd(t) (+4.8 to +6.9) were probably generated during back-arc extension by decompression melting of a mantle source metasomatized by adakitic slab melts formed during earlier stages of the subduction. This implies that the location of the back-arc was far from the subducted oceanic slab, possibly due to a slab rollback process. In this scenario, HNB intrusions provided the heat for partial melting and adakitic melt formation in the mafic lower crust. The model suggests that the Yuanmou and other similar associations of HNBs and adakitic rocks emplaced along the western margin of the Yangtze Block are products of a widespread Neoproterozoic back-arc extension. [ABSTRACT FROM AUTHOR]

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The Tak Batholith is located in the western part of Thailand’s eastern granitoid belt. To better understand the geochemical characteristics of granitoid and identify their occurrence, rock samples collected from the eastern part of the Tak Batholith were used for petrographical, mineralogical, and geochemical analyses. According to field investigation and lithology, petrography classifies these granitic rocks as medium-grained granodiorite and granodioritic dike. The granodiorites are composed chiefly of plagioclase, orthoclase, quartz, hornblende, and biotite, with tiny amounts of zircon, apatite, and opaque minerals. Meanwhile, the granitic dike shows a highly porphyritic texture, presenting mostly plagioclase phenocrysts, with a small amount of orthoclase and unidentified mafic phenocrysts sitting in a fine-grained groundmass comprising K-feldspar and quartz with a small amount of plagioclase and present granophyric intergrowth. Geochemical data of the amphiboles classified them as Ferro-edenite symbolizing the I-type granite. Whole-rock geochemistry indicates that these rock suites are I-type metaluminous granodiorite, and diorite fractionated from the high K calc-alkaline magma melted from the mafic crust of arc magmatism agreeable with the enrichment of large ion lithophile elements and depletion of highfield-strength elements, and rare earth element patterns.

The Los Cabos Block, at the southern end of Baja California, exposes part of the Late Cretaceous Peninsular Ranges Batholith over 2700 km2. In the Los Cabos block, the Los Cabos Batholitic Complex is exposed in two massifs, Sierra La Laguna to the west and Sierra La Trinidad to the east. The two sierras are separated by the ~75 km long, N-S striking, San José del Cabo extensional fault system, and the homonymous basin. Here, we present field observations, new U–Pb and Ar–Ar ages, and thermobarometric determinations to constrain the magmatic history of this composite batholith and the structural relations between Sierra La Laguna and Sierra La Trinidad. Field observations show that the batholith at Sierra La Laguna comprises several granodiorite bodies, felsic sills, and dikes with complex magma mingling and mixing features typical of an upper-middle crustal system within a mush zone of intermediate to silicic composition. U–Pb zircon crystallization ages for La Laguna massif define the main period of plutonism between ~89.9 and 73.9 Ma, with progressively younger ages from west to east. Zircon chemistry and published whole-rock isotopic data point to mantle contributions to arc magmatism with significant crustal thickening with time. Hornblende thermobarometry suggests a wide range interval of crystallization (depth: 12–18 km; temperature: 670–740°C). Sierra La Trinidad has a more felsic and narrow compositional range, with crystallization ages like those from the eastern, younger part of Sierra La Laguna and lower crystallization depth, indicating that it represents the shallower portion of the Los Cabos Batholitic Complex magmatic system. The integration of our study with previous research indicates that Sierra La Trinidad is the hanging wall block of the San José del Cabo fault system, which implies a low angle geometry (<30°) and older age of activation than previously considered (>18 Ma). [ABSTRACT FROM AUTHOR]

Outcrops of late Paleozoic magmatic rocks are common in the Southern Beishan Orogenic Belt (SBOB), Southern Central Asian Orogenic Belt (CAOB), which is a key object for the understanding of regional tectonism and defining the final closure time of the Paleo-Asian Ocean (PAO). We present zircon U-Pb chronology and whole-rock geochemistry data for late Paleozoic granodiorites and bimodal volcanic rocks from the Shuangyingshan-Huaniushan unit in the north Huitongshan-Zhangfangshan ophiolitic belt in the SBOB. The Zhangfangshan granodiorites (LA-ICP-MS, Ca. 288 Ma) are A2-type granite enriched in Rb, Th, Pb and LREEs and depleted in Nb, Ta, Ti, Sr, Ba and HREEs. They have varying MgO and TFe2O3 contents with high Mg# (38.56~48.97) values; the Lu/Yb ratios (0.14~0.15) of these granodiorites are similar to mantle-derived magma. A clear plagioclase zoning structure and acicular apatite occur in mineral assemblages derived from magma mixing between mafic and felsic magmas. The Baishantang bimodal volcanic rocks (272 Ma) consist of rhyolite and basaltic andesite. Baishantang rhyolites are A2-type felsic rock enriched in Rb, Th, Pb and LREEs and depleted in Nb, Ta, Ti, Sr, Ba and HREEs, with negative εNd(t) and εHf(t) (−5.2~−4.8 and −2.2~−1.9, respectively). Rhyolites originated from the partial melting of the crust, influenced by mantle material. Basaltic andesites belong to calc-alkaline series and have an enrichment of Rb, Ba, Th, U, Pb and LREEs, are weakly enriched in Zr-Hf, and are depleted in Nb, Ta, Ti and HREEs. The Nd-Hf isotopes of these basaltic andesites are not coupled with negative εNd(t) (−2.8~−0.4) and positive εHf(t) (1.8~5.5) values. These characteristics indicate that they originated from the partial melting of the mantle mixed with sediment-derived melts. In combination with previous studies, our findings show that the early Permian Zhangfangshan granodiorites and Baishantang bimodal volcanic rocks formed in a post-collision extensional setting, and the Huitongshan-Zhangfangshan ocean had been closed before early Permian. [ABSTRACT FROM AUTHOR]

The study presents detailed petrographical, geophysical, structural and geochemical data of the internal nappes zone to establish the deformational history, origin and tectonic setting and constrain the crustal growth and evolution of the active margin of the Dahomeyide belt. Two main lithological units, (i) deformed meta-granitoids (migmatites and gneisses) and (ii) undeformed granitoids, dominate the internal nappes zone. The granitoids are generally I-type, metaluminous to weakly peraluminous, low-K tholeiite to high-K calc-alkaline and of tonalite, granodiorite and granite affinity. The overall trace element patterns of the studied granitoids characterized by the enriched LILE and depleted HFS, with negative peaks of Nb-Ta, Sr, P and Ti, are indications of arc-related magmatism. Structural analysis reveals four deformation phases (D1-D4). D1 represents Northwest-Southeast (NW-SE) Pan African shortening associated with a continent-continent collision, resulting in westward nappe stacking. Progressive NW-SE shortening resulted in D2 and D3 top-to-the-NW dextral and sinistral thrusting events during the Pan-African orogeny. D4 is an extensional event likely associated with the orogenic collapse phase. The gneisses and migmatites, with dominant axial planar foliations, point to their formation in a collisional setting or influence by the Pan-African collisional processes. Continental-arc signatures in these rocks imply continental subduction during their protolith formation. The intrusive granitoid and pegmatite are undeformed, meaning late- to post-orogenic emplacement. These findings suggest that the internal nappes zone archived the subduction-collision and post-collisional phase of the Pan-African orogeny and recorded large-scale migmatization and granitoid emplacement due to partial melting of thickened lower crust between Mid-Cryogenian and late Ediacaran. [ABSTRACT FROM AUTHOR]

The geodynamic mechanisms that controlled magmatic activity in South China during the late Mesozoic have been a cutting-edge focus of recent research. Southeastern Guangxi, which is located at the juncture between the Pacific and Neo-Tethyan tectonic domains, is a transitional zone characterized by the occurrence of widespread Jurassic–Cretaceous magmatic rocks. Investigation of this region can shed light on the late Mesozoic tectonic setting of South China. We conducted U–Pb geochronological and geochemical analyses of the Liuwang granodiorite and quartz porphyry, which are exposed in southeastern Guangxi. Zircon U–Pb dating yielded an age of 161.8 ± 1.2 Ma for the granodiorite and 97.89 ± 0.68 Ma for the quartz porphyry, indicating that they formed during the Late Jurassic and Late Cretaceous, respectively. The Liuwang granodiorites are weakly peraluminous high-K calc-alkaline rocks characterized by enrichment in large ion lithophile elements (including Rb) and high field strength elements (including Th, U, Pb, and Ta) and depletion in Ba, Nb, and Sr. The granodiorites also exhibit weak rare earth element (REE) fractionation and slightly negative Eu anomalies. Conversely, the Liuwang quartz porphyry is weakly peraluminous and belongs to the potassic syenite series, transitioning into the high-K calc-alkaline series. It is characterized by enrichment in Rb and high field strength elements (including Th, U, Pb, and Ta), with depletion in Ba, Nb, Sr, and Zr. It does not exhibit REE fractionation but does yield prominent negative Eu anomalies. The granodiorite and quartz porphyry yield εHf(t) values of −23.26 to −2.48 and −4.4 to +0.8, respectively, with tDM2 ages of 2642–1270 and 1411–1081 Ma, respectively. These data suggest that the Liuwang granodiorite formed under a background of Late Jurassic lithospheric extension–thinning and was derived from partial melting of Palaeoproterozoic–Mesoproterozoic metasedimentary sandstones with a minor contribution from mantle-derived melts. In contrast, the Liuwang quartz porphyry was derived from partial melting of Mesoproterozoic pelitic rocks and formed in a Late Cretaceous tectonic setting linked to the northward subduction of the Neo-Tethys Ocean beneath South China. [ABSTRACT FROM AUTHOR]

An extended area of quarrying activity has been located at Xobourgo, on the Greek island of Tenos, where extraction continued for millennia to the north of the ancient settlement. The quarrying was centered on the protuberance of Xobourgo, a leucogranite outcrop that lies to the southwest of a larger granodiorite zone. The joint study of the material's properties, the quarry's layout, the extraction traces, and the use of leucogranite in constructions at Xobourgo shows that the quarrying activity was related to local building projects, especially fortifications. These are dated to the period that spans from the Early Iron Age (11th-10th century BCE) to the end of the Classical period (end of the fourth century BCE), as well as to the era of Venetian rule (1204-1715 CE). Extraction techniques differed through time depending on available tools, traditions, and the type of masonry. The leucogranite was exploited for its endurance, workability, and aesthetic value. Extraction so close to the adjacent settlement was also advantageous due to low transport costs. High levels of stoneworking skill, in line with the scale of constructions undertaken at the site, are diachronically attested. [ABSTRACT FROM AUTHOR]

Petrographic, geochemical and U-Pb geochronological research studies are done into cataclastic granitoids of the southeastern part of the Irkutsk block of the Sharyzhalgay basement uplift of the Siberian craton – the uplift which is considered southern part of the Tungus superterrane according to most of tectonic schemes. The representative sample of these granitoids corresponds to granodiorite in its geochemical properties and is characterized by high contents of Al2O3, Th, Sr, Ba, low concentrations of K2O, Nb, Y, Yb, a highly fractionated rare earth elements pattern (Lan/Ybn=284), and the absence of europium anomaly. U-Pb geochronological studies of zircon from cataclastic granodiorite were carried out independently by two methods: SIMS and LA-ICP-MS, which showed good consistency of the results. The U-Pb age of the cores of zircon grains with magmatic zoning corresponds to 2893±19 Ma (SIMS method) and 2889±16 Ma (LA-ICP-MS method). These results can be interpreted as the age of the Archean granodiorite protolith. The rims of zircon crystals with the Archean cores, as well as the individual zircon crystals with parallel zoning, yielded ages of 1855±6 Ma (SIMS method) and 1864±5 Ma (LA-ICP-MS method), which record the time of granodiorite transformations. The age of about 1.86 Ga corresponds to the main Early Proterozoic stage of metamorphism, migmatization and magmatism, which show their widespread occurrence in the Sharyzhalgay basement uplift. This age estimate together with the previously published ages for metamorphic and their synchronous magmatic events in the Sharyzhalgay uplift allowed concluding that the Tungus superterrane joined the earlier formed core of the Siberian craton in the time interval 1.85–1.88 Ga. The final stage in the Siberian craton formation is the development of the South Siberian post-collisional magmatic belt, intersecting all large Early Precambrian blocks of the southern part of the Siberian craton, already united into a single structure.

The Mid-German Crystalline Zone (MGCZ) is a key region to decipher the evolution of the Variscides. Deformational processes in the Böllstein Odenwald as an integral part of the MGCZ have been studied in the past, but the exact time frame remained uncertain. Therefore, a study combining structural analysis and age dating (U-Pb on zircon) was carried out at the Weichberg quarry, where the contact between metagranitoid core and metasedimentary schist envelope of the Böllstein Odenwald is well exposed. Schist envelope rocks and Silurian granodioritic sills intruded therein show at least two folding phases: Recumbent tight to isoclinal folds are overprinted by upright gentle folds. A pegmatite dike, intruding at 411 ±2 Ma into the schist envelope rocks, crosscuts perpendicular to their main foliation and shows only a weak schistosity related to the isoclinal folding. Consequently, isoclinal folding must have been active before 411 ±2 Ma (Lower Devonian), but after the Silurian intrusion age of the granodiorite sills (ca. 423 Ma; Dörr et al. 2022). At Weichberg quarry the core is represented by a (meta)granite without isoclinal folding, intruding into the schist envelope at 404 ±2 Ma. Post-intrusive tectonic displacements along the contact between metagranite and metasediments are indicated by fold deformation directly above the contact and by dikes terminating at the contact. Deformations described in this work probably result from the collision of the MGCZ with the NW edge of the Saxothuringian Zone. Similarities with respect to intrusion age and deformation age/style can be found in other units within the European Variscides for example the Léon Domain (e.g. Faure et al. 2010) or the Ossa-Morena Zone (e.g. Simancas et al. 2001). [ABSTRACT FROM AUTHOR]

The Jiaodong gold mineralization is closely related to intermediate-felsic granitoids. The Linglong-type gneissic biotite granite(the age is 160-153 Ma)being shear facies is a large batholith with an area of 3 500 km². The Luanjiahe-type equite-grained and coarse-grained monzogranite(the age is 154-152 Ma)being extension facies intrudes into the Linglong-type gneissic biotite granite, with a single area of 100 km² to hundreds square kilometer. But the most closely related to gold mineralization is the Guojialing-type porphyritic granodiorite(the age is 131-126 Ma)with compression facies, and it mainly exposes as stocks(the area is 2-90 km²), which are close to giant gold deposits within 5 km. However, when the Guojialing-type porphyritic granodiorite has a large outcrop(such as the Guojialing granodiorite pluton in Penglai having an outcrop of 270 km²), it is almost irrelevant to gold mineralization. The new cognition from the “small intrusion forming large deposit” of Jiaodong intermediate-felsic granite has great research significance and application value for the study on metallogenic regularity and mineral prospecting of intermediate-felsic magma-related hydrothermal deposits. But the relevant data still need to be extensively studied, and its genetic mechanism is being deeply explored. [ABSTRACT FROM AUTHOR]

The Middle Triassic Pingtai pluton, which occurs in the southeastern part of Wulonggou gold orefield, East Kunlun orogen, provides new insights into the subduction history of the Paleo-Tethyan ocean. The detailed petrology, whole-rock geochemistry, zircon U-Pb age and Hf isotopic data of granodiorite from Pingtai pluton were conducted. The results show that the granodiorite of Pingtai pluton mainly comprises plagioclase(the volume fraction is 45%-50%), quartz(20%-25%), K-feldspar(20%-25%), hornblende(5%), and biotite(5%), and it yields a zircon U-Pb weighted mean age of(247±1)Ma, suggesting an emplacement age of Middle Triassic; whole-rock geochemistry characteristics show that SiO2 content varies from 64.88% to 65.90%, average ratios of FeOT/MgO and Fe2O3/FeO are 3.70 and 1.48, respectively, and average saturation temperature for zircon is calculated to be 770 ℃. Therefore, it is suggested that the granodiorite belongs to strong peraluminous and high-potassium calcium alkaline series, which is similar to typical I-type granite. Chondrite-normalized REE pattern shows that the granodiorite is enriched in LREEs and depleted in HREEs with weak negative Eu anomaly. The εHf(t)values range from -4.51 to 0.64, and the Hf model age is 1.54-1.22 Ga. In combination with regional geological data, it is suggested that the granodiorite of Pingtai pluton is generated in a continental magmatic arc setting, which is related to the northward subduction of the Paleo-Tethyan ocean, and its parental magma is derived from meta-sandstone of continental crust. It is further indicated that the subduction of the Paleo-Tethyan ocean might have lasted until the late Middle Triassic. [ABSTRACT FROM AUTHOR]

A submarine dune on the seabed in the Okinose area of Osaka Bay, Japan, was found to be composed mainly of coarse quartz sand. To investigate the provenance of this sand, quartz extracted from granite and granodiorite sources near Osaka Bay was measured by electron spin resonance; E1′, Ti-Li and Al centres were detected in all samples. Although the heat-treated E1′ centre was found not to be useful for the present provenance study, the ratio of the signal intensities of the Ti-Li centre to the Al centre classified the potential sources into two groups, based on their likelihood. The results indicated that granite and granodiorite from Awaji Island as well as Rokko granite could be the source of the Okinose sand. [ABSTRACT FROM AUTHOR]

Studies assessing the potential of mining areas for carbon sequestration focused mainly on areas after the extraction of energy raw materials, especially coal or oil shale, but little attention was paid to stone quarries and quarries of other non‐energy raw materials. We investigated carbon and nitrogen pools (stocks) along a chronosequence in the organic horizon and to a depth of 20 cm of the mineral soil in granodiorite quarries. We compared these pools and sequestration rates with other mining sites. The advantage of this study is that several differently aged quarries in a small area have the same rock chemistry and climate. Thus, the rate of pedogenesis is purely a function of time and vegetation. It is not affected by fossil organic matter or organic matter and nutrients in the topsoil used for reclamation. The vegetation succession tends towards tree cover dominated by Pine (Pinus sylvestris), Birch (Betula pendula), Willow (Salix caprea), Aspen (Populus tremula) and Alder (Alnus glutinosa). Analysis of soils from granodiorite quarries showed a natural accumulation of carbon and nitrogen in the soil to a depth of 20 cm during about 60 years of natural succession. The total soil organic carbon and nitrogen pools to a 20 cm depth average of 2482.4 g C m−2 and 179.1 g N m−2, respectively, in the oldest plots >50 years old. These values are for carbon 2.6 and nitrogen 2.4 times lower compared to pools in the same depth on control plots. Carbon and nitrogen stocks and sequestration rates are lower than in compared coal mining sites and spoils. The sequestration rates of the total sampled soil profile decreased with time from 57 g C m−2 year−1 and 4 g N m−2 year−1 for sites younger than 25 years to 46 g C m−2 year−1 and 3 g N m−2 year−1 for sites older than 50 years. [ABSTRACT FROM AUTHOR]

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We have studied the geological structure, material composition of the ores, and the age of the Nizhny Birkachan volcanogenic gold–silver deposit discovered recently. The ore bodies consist of veins and vein-streak zones of adularia-carbonate-quartz composition; they lie in granodiorite porphyries with U‒Pb zircon age (ID-TIMS) equal to 335 ± 2 Ma. The ores are low sulfide, low silver (Au/Ag = 1–2), with pyrite dominating the ore minerals. The Ag minerals are tennantite, Ag sulfide, native gold and silver, and hessite. From an ore vein we obtained an adularia-based 40Ar/39Ar age equal to 169 ± 4 Ma, which reflects the rejuvenation of the isotopic argon system after the emplacement of a dike of unaltered Jurassic basites that cuts through the ore body. The Nizhny Birkachan deposit has a geological structure and ore composition that are very similar to those of other Au-Ag deposits at the Kedon volcano-plutonic belt such as Kubaka and Birkachan; it was also formed in the age span 290–335 Ma. [ABSTRACT FROM AUTHOR]

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Miocene Tipam Sandstone Formation in parts of Cachar Fold Belt, Northeast India has been studied using petrographic and geochemical attributes to investigate the composition, paleoweathering, tectonic setting, and source rock characteristics. It comprises of coarse to medium grained false-bedded multistoried ferruginous sandstone and variegated sandy clay. Petrographically, these sandstones belong to sub-lithic and lithic arenite varieties possessing an average recalculated modal composition of Q67F13R20. Geochemically, Tipam sandstones have high SiO2, more Na2O than K2O, and relatively low Fe2O3, MgO, MnO content in accordance with the modal composition. Weathering indices like CIA, CIW, PIA and ICV suggest derivation of sediments from low to moderately weathered source terrain bearing plagioclase feldspar in the range of An10–An55 comparable to granodiorite and granite composition. Dominantly a passive margin setup with high degree of sediment recycling has been envisaged during the deposition of Tipam Sandstone Formation. [ABSTRACT FROM AUTHOR]

The La Cocha-Río Téllez Migmatitic Complex is located on the eastern flank of the Colombian Andes, between the departments of Nariño and Putumayo. It crops out as windows between recent volcanic and fluvio-volcanic deposits. Under the name of La Cocha-Río Téllez Migmatitic Complex, granitoids, quartz-feldspar-moscovite and biotite gneisses, tonalites, mylonitic metatonalites and migmatitic amphibolites of different age and geological environment were grouped. According to our results, in this contribution we propose to stop using the name La Cocha-Río Téllez Migmatitic Complex and henceforth use the formal names of five units that represent different metamorphic and igneous events, formed between the Devonian (?) and Oligocene, which we propose to call as follows: the Sibundoy Gneiss to the unit with metamorphism ages between 365.97 ± 12.8 Ma and 386.78 ± 15.9 Ma, the San Francisco Schists with ages around 163 Ma, the Motilón Granodiorite to the pluton with crystallization ages between 172. 7±1.4 and 152.2 ± 0.31 Ma, the Alisales Tonalite to the pluton with crystallization ages of 32.4 ± 0.58 Ma, and the Tellez River Amphibolites to the unit with metamorphism ages of 80.4 ± 1.5 Ma. [ABSTRACT FROM AUTHOR]