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The timing of high-pressure (HP) metamorphism in the eastern Himalayan syntaxis is important for understanding the India-Asia collisional processes, but it remains elusive. To reveal the metamorphic history of the eastern Himalayan syntaxis, we performed a study of geochronology, trace elements, and mineral inclusions of detrital zircon and monazite from modern stream sediments in the eastern Himalayan syntaxis. Detrital zircon comprise magmatic and metamorphic domains with different zoning. Inherited magmatic zircon domains have high Th/U, low (Dy/Yb)N, and retain ages of 1798−360 Ma. Metamorphic zircon domains with low Th/U, high (Dy/Yb)N, and inclusions of garnet, kyanite, and/or clinopyroxene probably formed under HP conditions. They yield age groups of 49−35 Ma, 33−17 Ma, and 12−7 Ma. The low Th/U and low (Dy/Yb)N metamorphic zircon domains probably formed during retrogression and yield age groups of 27−16 Ma and 10−6 Ma. Detrital monazite yield age distributions similar to those of the low (Dy/Yb)N metamorphic zircon except for the 821−402 Ma inherited cores. The (Dy/Yb)N of 31.6−5.7 Ma monazite decreases with increasing Y content, which indicates that it likely formed under the retrograde stage during garnet breakdown. Based on the oldest metamorphic ages, the initial India-Asia collision occurred no later than 50−44 Ma in the eastern Himalayan syntaxis. The multimodal age patterns of the metamorphic zircon and monazite indicate that the Indian continent underwent multistage HP and retrograde metamorphism in the eastern Himalayan syntaxis. The nearly contemporaneous HP and retrograde metamorphism indicate that the Indian continent continued subducting while the earlier HP metamorphic slices detached and exhumed.

Table S1: Zircon LA-ICP-MS U-Pb data of the early Jurassic mafic rocks from the Kaqiong microblock; Table S2: Zircon LA-ICP-MS REE (ppm) data of the early Jurassic mafic rocks from the Kaqiong microblock; Table S3: Whole-rock major (%) and trace (ppm) element data of the early Jurassic mafic rocks from the Kaqiong microblock; Table S4: Zircon LA-MC-ICP-MS Lu-Hf data of the early Jurassic mafic rocks from the Kaqiong microblock; Table S5: Whole-rock Sr-Nd isotopic data of the early Jurassic mafic rocks from the Kaqiong microblock.

Upper Permian to Lower Triassic siliciclastic succession in the Shiwandashan Basin, South China, accumulated in response to a Permo-Triassic orogeny (often referred to as the Indosinian orogeny). The petrology, geochemistry and geochronology of this succession, along with north and northwest-directed paleocurrent indicators, reveal an evolving provenance related to erosion and reworking of Precambrian, Early Paleozoic and Permian to Early Triassic units exposed to the south of the basin. The Upper Permian to Lower Triassic sandstones within the basin are quartz dominated, which along with their high Th/Sc and Zr/Sc ratios indicate a multi-cycled source. Sandstone clasts in the Upper Permian conglomerates display age patterns similar to nearby Silurian strata. Other clast types (limestone, mudstone and cherts) are from the Early Paleozoic strata within or adjoining the basin. Detrital zircon age spectra of the strata display prominent age groups at 1200–800 Ma, 650–500 Ma and 460–420 Ma, and are inferred to have been derived from basement units similar to those exposed in the Yunkai Massif to the south and southeast of the Shiwandashan Basin and/or from reworking of the Paleozoic units around the basin. The Lower Triassic strata also contain 260–240 Ma zircons that were likely derived from magmatic rocks located to the south of the basin. The Late Permian marks a significant change in the paleogeography of the Shiwandashan Basin from an older deep marine chert succession to a terrestrial to shallow marine environment receiving an influx of clastic detritus related to uplift and erosion to the south of the basin. The Lower Triassic units within the basin record a further pulse of sediment influx including detritus derived from approximately syn-sedimentary magmatic activity. Yunkai Massif, located in the southeast of the basin, underwent uplift in Late Permian and provided majority detritus for the basin in the Late Permian to Early Triassic. Integration of provenance data with regional geological information, magmatic and metamorphic records to the south of the Shiwandashan Basin suggests the basin was converted from a pre-Late Permian deep marine extensional basin to a Late Permian to Early Triassic foreland basin. Conversion to a foreland basin reflected collision between the South China and Indochina blocks.

Objective: The medical staff fighting against COVID-19 virus are under great pressure. Anxiety and insomnia are common problems that are experienced and which need to be actively addressed when they returned from the epidemic front line. Five-element music (a kind of Chinese traditional music) has been tried for this purpose. Subjects and Methods: The medical staff who volunteered to participate in the trial were randomly divided into two groups. After a questionnaire and classification of their emotional type, both the groups received general music exposure. Then, Chinese five-element music is offered to the study group. After the trial, the improvement of anxiety and insomnia was evaluated by comparing the Self-Rating Anxiety Scale (SAS) and Self-Rating Scale of Sleep (SRSS) scores before and after the intervention. Results: The SAS and SRSS scores of the two groups demonstrated no obvious difference before recuperation and the number of people taking medicine was roughly the same. After the intervention of Chinese five-element music, the SAS and SRSS scores were comparatively better (P

Granitoids are widespread in the Songpan-Garze (松潘-甘孜) fold belt, western China. These granitoids provide insight into regional tectono-magmatic events, basement nature and tectonic evolution. However, previous studies mainly focused on the eastern Songpan-Garze fold belt. In this article, five granitoid intrusions from the western Songpan-Garze fold belt have been studied. These intrusions are composed of quartz-diorite and granodiorite. Using LA-ICP-MS zircon dating method, the obtained magma crystallization ages are 219±2 Ma for the quartz-diorite and 216±5 Ma for the granodiorite. The ages, combined with regional geological analyses, show that they formed in a post-collisional tectonic setting. The quartz-diorite and granodiorite display co-linear variation in their chemical compositions. REE compositions for both the quartz-diorite and granodiorite show strongly fractionated patterns with (La/Yb)N=5.02–18.34 and Eu/Eu*=0.44–0.89. The quartz-diorites have initial 87Sr/86Sr ratios (ISr) of 0.709 29–0.711 97 and ɛNd(t) values of −8.6 to −6.1 and the granodiorites have ISr values of 0.705 49–0.709 97 and ɛNd(t) values of −8.3 to −4.3. Zircon Hf isotopic data show ɛHf(t) values of −3.8 to +1.6 for the quartz-diorites and −1.2 to +3.0 for the granodiorites. Geochemical and Sr-Nd-Hf isotopic compositions indicate that the quartz-diorites and granodiorites have similar petrogenesis. We suggest that the magmas for the quartz-diorites and granodiorites were derived from partial melting of lower crustal mafic source, resulting from amphibole dehydration melting reaction. The probing of the magma source reveals that the western Songpan-Garze fold belt contains an unexposed continental basement, which is similar to the eastern Songpan-Garze fold belt. Geodynamically, it is proposed that a lithospheric delamination model can account for the magma generation for the quartz-diorites and granodiorites in the western Songpan-Garze fold belt.

In order to constrain the formation time of high-grade metamorphic rocks in the Qilian Mountains, U-Pb zircon dating was carried out by using LA-ICPMS technique for a paragneiss of the Hualong Group in the Qilian Mountains basement series and a weakly foliated granite that intruds into the Hualong Group. Zircons from the paragneiss consist dominantly of detrital magma zircons with round or sub-round shape. They have 207Pb/206Pb ages mostly ranging from 880 to 900 Ma, with a weighted mean age of 891 ±9 Ma, which is interpreted as the magma crystallization age of its igneous provenance and can be taken as a lower age limit for the Hualong Group. Magma crystallization age for the weak-foliated granite is 875±8 Ma, which can be taken as an upper age limit for the Hualong Group. Accordingly, the formation time of the Hualong Group is constrained at sometime between 875 and 891 Ma. A few zircons from both paragneiss and weak-foliated granite display old inherited ages of 1000 to 1700 Ma and young metamorphic ages of Early Paleozoic. The zircon age distribution pattern confirms that the Qilian Mountains and the northern margin of Qaidam Basin had a united basement, with geotectonic affinity to the Yangtze Block. The results also reveal that sediments of the Hualong Group formed by rapid accumulation due to rapid crustal uplift-erosion. This process may result from intensive Neoproterozoic orogenesis due to assembly of the suppercontinent Rodinia.