The Paleotethyan tectonic history of northeast Tibet remains hotly debated, particularly regarding the nature of the Jinsha suture. Different interpretations of the Jinsha suture lead to different tectonic reconstructions of northeast Tibet, southern Eurasian continent. We identified three tectonic units along the western segment of the Jinsha suture in the Yushu–Zhiduo region: the Bayan Har–Songpan–Garzê fold belt (BSB), the Yushu mélange, and the eastern portion of the Qiangtang block (EQ). New geochemical and geochronological studies help to identify a Triassic continental magmatic arc (the Yushu arc) that developed upon the EQ and that is geochemically similar to magmatism in the Yidun arc. Structural studies, combined with 40Ar/39Ar analyses, reveal a complex deformational history of the Yushu–Zhiduo region: earlier‐stage top‐to‐the‐north asymmetrical fabrics are preserved exclusively in the Yushu mélange, which yields a phengite 40Ar/39Ar age of 230.5 ± 0.8 Ma; later‐stage orthogonal fabrics developed in the BSB and EQ (superposed upon the earlier fabrics in the Yushu mélange), likely resulted from a collision between the BSB and the Yushu arc that continued until ∼195 Ma. The structural patterns and deformation history of Yushu arc region are comparable with those recorded in the Yidun arc region. Thus, the previously defined Jinsha suture should be subdivided into western and southern segments. The western Jinsha suture is continuous with the Garzê‐Litang suture, while the southern Jinsha‐Ailaoshan suture marks the site of the closure of several intracontinental rift basins that have likely been overprinted by intra or back‐arc extension.

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Oxygen-deficient zinc oxide thin films were deposited by radio frequency magnetron sputtering with a sintered zinc oxide ceramic target under an atmosphere of manipulated sputtering gas pressure (SGP). Under the designed deposition conditions, all the prepared films were of hexagonal würtzite structure with c-axis as the preferential growth orientation. With increasing SGP, the film thickness, deposition rate, grain size and atomic ratio of O to Zn in the films initially increased and then decreased. Interestingly, when the SGP was low, the main defects in the films were oxygen vacancies; when it was high, the dominant defects were interstitial zinc; but when it was in a moderate value, the film composition might be relatively close to the stoichiometric ZnO, possessing the least number of defects. As a result, the electrical resistivity of the films first increased and then dropped down as the SGP increased.

Previous studies suggested an important, but yet poorly-understood, tectonic transition in the Altaids (also termed the Central Asian Orogenic Belt, CAOB) in the Permian. This tectonic transition, clearly documented by published stratigraphic data and provenance analyses, suggested a unified Junger-Turfan basin in northwest China in Permian time and it further indicated that extension dominated Early Permian tectonics in the region, whereas flexural, foreland subsidence controlled Late Permian basin evolution. Our new structural observations, microtectonic analyses, and 40 Ar/ 39 Ar geochronological data from southwest of the Turfan basin reveal that in the late Early Permian (266 Ma) a NS-directed contractional deformation operated along the southern border of the unified Junger-Turfan basin, which was probably related to the transition in basin evolution. The contraction gave rise to a NW-striking right-lateral transpressional, rather than simple-shear dextral, ductile shear zone along the southwestern border of the Turfan basin, and to an interference fold pattern together with closely-spaced, concentrated cleavage and thrusts in a constrictional strain regime in the basin interior. After the Late Permian the tectonic evolution of the CAOB changed from Paleozoic continental amalgamation to Mesozoic-Cenozoic intracontinental orogenic reactivation.

Numerous materials have been proposed for thermoluminescence dosemeter, and the example of highest sensitivity is cited as magnesium orthosilicate doped with terbium (Mg2SiO4:Tb). Nevertheless, the material is currently not commercially attractive because the sensitivity varies greatly with synthesis techniques. This is a multi-parameter problem, and the current work explores some of the conditions required to consistently enhance the response. These new results show that to get a high TL response, Mg2SiO4:Tb should be prepared at a high temperature of at least 1500°C, for sintering times of several hours. In the current example, the optimum time was 6 h. Signals also vary with the terbium activator concentration, and good responses were achieved with a concentration of Tb at 5 wt %. Overall, this suggests that with careful preparation, the potentially high dosimetry performance might be exploited. The inherent problem of concentration quenching is considered, and the potential benefits of processing the powder with pulse laser annealing are reviewed in the light of successful luminescence and laser studies for rare-earth-doped laser materials.

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