The Neoproterozoic (900-600 Ma) Arabian Nubian Shield is an example of Precambrian plate tectonics and arc accretion. The Western Ethiopian Shield (the southern extension of ANS) is geo-tectonically a characteristic of lower grades of Metavolcano-sedimentary sequences of ANS intruded by associated felsic granitoid and mafic bodies and at the same time it is contained of gneisses rocks of the MB. The Gold mineralization and alterations initiating throughout the Tulu Kapi syenite are in the form of in enechelon vein arrays and related structures, which are controlled by conjugate shear zones in the syenite and steep N-S striking structures. The earliest recorded deformation and alterations revealed the syenite albitization which is the one hosting for gold mineralization and it has been widely overprinted by multistage hydrothermal system that appears to have been controlled mainly by veins, crackle zones, fractures and minor breccia zones. Primary gold mineralization displays spatial and temporal relationship with Tulu Kapi syenite and the Kapi gabbro, both of which host gold mineralization, are 738.3±2.6 Ma and 699.5±2.7 Ma period, respectively, in a volcanic arc subduction syn-collisional tectonic setting by the fractionation of underplated, LREE-enriched basaltic magma with substantial crustal input to possible crustal melting. The underplated basaltic magma had been sourced from LREE-enriched mantle by subduction of sediment laden crustal slabs at a subduction zone. Fractional crystallization involved formation of Ca-rich plagioclase, which continually reacted with hydrothermal fluids to more fractionated Na-rich plagioclase, forming the gold mineralization hosting altered (albitized) syenites. The Pan-African orogeny, and associated regional metamorphism and magmatism, generated large-scale movements of gold and base metal-bearing fluids in the crust, channelized along complex fractures into regional NE-SW foliation in Ethiopia (e.g., western Ethiopia). However, these gold-rich alkalic magmas are so modified by crustal processes that evidence of their genetic relationship with gold become obscured. The primary ore mineral assemblage of quartz veins and veinlets, and associated mineralised syenite within Tulu Kapi area consists of pyrite, galena, chalcopyrite, hematite, and gold. The major and trace element composition of ore- forming fluids from the mineralised vein, barren and granitic intrusion is still largely unknown, yet could provide important and more direct evidence for the fluid source(s). This is vital in establishing a direct genetic link between syenite and other granitoid intrusion, and gold mineralization.

The Kuznetsk Basin (Kuzbass) is one of the largest coal basins in Siberia and a reference area for the ancient Angaraland continent. The proximity of the Kuzbass and Siberian platform caused their biotic similarities in the Late Palaeozoic. However, due to biota endemism, the Kuzbass Upper Palaeozoic does not correlate directly with the International Chronostratigraphic Chart (ICC). This paper discusses radioisotopic (CA-ID-TIMS) dating of zircons from a volcanic tuff located in the Starokuznetsk Formation. This level matches the interval of the Balakhonka/Kolchugino (B/K) floral change in Kuzbass, i.e. the gradual replacement of cordaitoid-dominated wet forests (Balakhonka flora) by more arid fern-pteridosperm-cordaitoid assemblages (Kolchugino flora). New age (276.9 ± 0.4 Ma) directly correlates the Starokuznetsk Fm with the Upper Kungurian of the ICS. We compared the Kuzbass data with data of the Western Verkhoyanie, where Middle Permian ammonoids (Sverdrupites assemblage) occur in strata recording the B/K floral change. Available (ICC) and new datings indicate the lag between the B/K floral change in low (Kuzbass) and high (Verkhoyanie) latitudes of Angaraland. The B/K floral change in the Kuzbass began in the early Late Kungurian and was completed by the end of this age. In contrast, the B/K floral change in Verkhoyanie began at the end of the Late Kungurian and was completed in the Late Wordian. The delay in the floral changes at different latitudes of Angaraland suggests that existing interregional correlations need further improvement.

Precise determination of the tectonothermal events at the Qinling-Qilian junction is extremely significant for understanding the tectonic evolution of the eastern branch of the Paleo-Tethys. The Banpo porphyry outcrops in the northern margin of the North Qinling were chosen as the research subject, and its formation and tectonic environment were analyzed using Zircon U-Pb age estimation and geochemical studies. The results indicated the final stage of the Triassic orogeny and the closure phase of the Paleo-Tethys. The weighted average values of 206Pb/238U ages of samples from 3 sites of the Banpo porphyry corresponded to 213.4 ±2.1 Ma (MSWD = 0.56), 213.0 ±1.6 Ma (MSWD = 0.92), and 213.2 ±4.4 Ma (MSWD = 1.6). This study revealed that the Banpo porphyry was formed during the Late Triassic (Norian). The porphyry with high SiO2 and high alkali is typical A-type granite, which belongs to the weak peraluminous shoshonite series. All the samples are rich in low rare earth elements. However, the heavy rare earth elements are low, especially Eu, which exhibits a seagull-type right-leaning partitioning curve. In addition, based on the regional geological data, it can be concluded that the Banpo porphyry was formed during the transition period from a post-orogenic environment to a non-orogenic environment. This study indicated the closure of the Paleo-Tethys-Mianxian-Lveyang Ocean by the Late Triassic as well as the completion of the collision between the North China and Yangtze Blocks along the Qinling orogenic belt.

Western Anatolia comprises a vast amount of various volcanic successions spanning from Eocene to Upper Miocene periods. These units mainly display southward younging in broad sense and display large amounts of chemical variation that spanned from basalt to rhyolite. The southward younging of magmatism and chemical variations have been largely attributed to the retreat and roll-back of the Hellenic slab and the western escape of the Anatolian microplate. However, there is still a lack of high precision data to pinpoint the exact nature of the magmatism and lithospheric tectonics. In this contribution we investigated a poorly known region along the Western Anatolia along Manisa district called Karakılıçlı volcanic field. We investigated two different volcanic sections (Kalpakkaya and Çamlık hill) that display the best volcano-sedimentary features in terms of geochronology and geochemistry. Samples acquired from the bottom, middle and upper portions of these sections display Early-Middle Miocene ages of 17.64±0.20, 17.22±0.15, 16.16±0.17 and 16.36±0.13, 15.79±0.71 and 13.61±0.20 Ma respectively. The results indicate that the volcanism in the region generated by the melting of the mantle and/or lithospheric mantle by slab retreat and roll-back of the Hellenic slab and evolved in the shallow magma chambers/mushes by fractional crystallization, magma mixing and crustal assimilation.

As the largest accretionary orogen in the world, the Central Asian Orogenic Belt (CAOB) has continuous juvenile crustal growth in the Phanerozoic. The northern margin of the North China Craton(NCC) and its adjacent area is the eastern segment of the CAOB, and is a key area to study the geological evolution of Paleo-Asian Ocean (PAO). In the Permian, the west of the northern margin of NCC belongs to a post-collision extensional environment, and the east belongs to a subduction stage. But, As a connecting area, the Permian evolution of PAO in the middle of northern margin of NCC has not been systematically studied. In order to fill the blank and understand the temporal and spatial continuous evolution process of PAO, this paper focused on the Permian granitic rocks in the Chifeng area, zircon U-Pb dating and the geochemical analysis of the whole rock main and trace elements were conducted in order to build a granite chronological framework, discuss the genesis and tectonic background of the granite rocks as well as the magma-tectonic evolution history in the Chifeng area. Zircon U-Pb dating results of 8 samples are 269±1 Ma, 268±3 Ma, 260±4 Ma, 260±1 Ma, 260±1 Ma, 255±2 Ma, 254±2 Ma, 256±1Ma, which showed that the Permian granitic rocks had undergone three stages of emplacement: (1) The monzogranite and syenite (294-284 Ma); (2) The monzogranite (269-260Ma) and (3) The monzogranite and syenite (256-254Ma). The Middle Permian magmatism (269-260Ma) was represented by the monzogranite assemblages with different grain sizes. The geochemical characteristics showed that they were high-potassium calc-alkaline-potassium dossonite series of granites formed in compressional environment, indicating there was a collision between the Xing’an-Mongolian Orogenic Belt (XMOB) and the North China Craton (NCC). During the Late Permian-Early Triassic (256-248Ma), the granites in the Chifeng area are dominated by the A-type and I-type granites of high-potassium calc-alkaline series formed under an extensional environments, which constituted typical "bimodal" rock assemblage combined with the coeval basic rocks, suggesting the study area was in an extensional environment where the subducting slab is fragmented during the collision between the XMOB and the NCC. According to emplacement time and occurrence location, the plutons are interpreted to have been generated by the subduction-collision of the Paleo-Asian oceanic crust beneath the NCC. This study provides strong evidence for Permian tectonic evolution and the characterization of the eventual closure of the Paleo-Asian Ocean in the Chifeng City at the northern margin of the NCC.