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The Luobei Complex in Northeast (NE) China lies in the northern Heilongjiang Complex and comprises a sequence of low-temperature–high-pressure metamorphic rocks distributed along the N–S-oriented suture zone between the Jiamusi and Songliao blocks. However, the timing of formation and tectonic setting of the Luobei Complex remain poorly constrained. Here, we present petrological, geochronological, and geochemical data for metasedimentary rocks from the Luobei Complex to elucidate its origin and tectonic setting. The Luobei Complex is characterised by the occurrence of serpentinite, blueschist, greenschist, amphibolite, and marble, which form lenses or interlayers in a matrix of two-mica schist, albite schist, quartz schist, and granitic gneiss. Zircon U–Pb dating of four metasedimentary rocks yields consistent Late Triassic maximum depositional ages (ca. 214 Ma). Detrital zircons from the Luobei Complex yield ages ranging from 1889 to 202 Ma, with age peaks at 504, 350, 265, and 214 Ma. The ages prior to 350 Ma exist in both the Jiamusi Block and the Central Asia Orogenic Belt (CAOB), indicating that the syn-deposition of Luobei Complex, meanwhile, the lack of ages younger than 350 Ma suggests that the Jiamusi Block rifted eastward from the CAOB. Geochemical data indicate that the studied metasedimentary rocks were formed in a continental island arc setting. These results, together with the Early Jurassic metamorphism reported by previous studies, constrain the timing of final collision to Late Triassic–Early Jurassic after subduction of the Jiamusi Block beneath the Songliao Block. Combining our new results with previous findings, we propose a new tectonic model: (1) during the latest Carboniferous to Late Triassic, the Jiamusi Block rifted from the CAOB as a result of Mongol–Okhotsk oceanic plate subduction; and (2) during the Late Triassic and Early Jurassic, the Jiamusi Block was reunited with the Songliao Block, and the Heilongjiang Complex formed, as a result of Paleo-Pacific plate subduction. [ABSTRACT FROM AUTHOR]

The Jiamusi Block is an important tectonic unit in the Chinese segment of the CAOB. Its eastern margin became an active continental margin in the period of Late Carboniferous. However, the tectonic affinity of this section has not been resolved yet. The Early Permian andesites within the Erlongshan Formation in the eastern Jiamusi Block provide a critical record for the active continental margin setting. Precise LA‐ICP‐MS U–Pb zircon dating on four andesite samples gave ages of 280 ± 3 Ma, 282 ± 3 Ma, 286 ± 4, and 284 ± 2 Ma, respectively, defining an Early Permian age for the crystallization of the andesites. The andesites have medium‐K and calc‐alkaline compositions, with variable SiO2 (54.70–57.46 wt%), TiO2 (0.87–1.12 wt%), TFe2O3 (6.52–8.13 wt%), MgO (2.62–3.33 wt%), Al2O3 (15.96–17.83 wt%), Na2O (3.28–4.10 wt%), and K2O (1.16–1.95 wt%) contents. They are relatively enriched in LREEs ((La/Yb)N = 5.0–7.1) and LILEs (e.g., Ba, Th, Sr, and U), deleted in HREEs and HFSEs (e.g., Nb, Ta, Zr, and Y) and have weak or no Eu anomalies (Eu/Eu* = 0.87–1.02). These geochemical features indicate that the andesites within the Erlongshan Formation originated from an active continental margin setting, and their magma source was produced by partial melting of a mantle material that had been metasomatized by subduction‐related melts and subsequently underwent the removal of mafic minerals and accumulation of plagioclase. Integrated with previous studies on the igneous and sedimentary rocks, we thus propose that the Jiamusi Block was in an active continental margin setting in the period of the Late Carboniferous to Early Permian (310–280 Ma), and it is more likely related to the subduction of the Mongol‐Okhotsk Ocean. [ABSTRACT FROM AUTHOR]

Taking Sihe Mine for background, according to additional hydrogeological exploration, the water resistance properties study about Fengfeng Group was done to prove the existence of relative aquifuge. At last, numerical simulation by FLAC3D was done when relative aquifuge exists to prove that the mining condition in deep part resource with water pressure gets clear improvement. So one of the key factors to do research in this condition is to find out whether the top part of Ordovician gets enough water resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • The west Jiamusi-Khanka Block in a passive continental margin setting by 300 Ma but an active continental margin by 270 Ma. • The Heilongjiang Ocean account for the transition from a passive to an active continental margin setting. • A new essential tectonic framework for the composite orogenic metallogenic system in the east of North China. Since the Paleozoic, the composite orogenic belt in the east of North China (the eastern Central Asian Orogenic Belt) has undergone multiple stages of subduction-accretion, tectonic superposition and destruction driven by multiple tectonic domains, e.g., the Paleo-Asian Ocean, the Panthalassa, and the Paleo-Pacific Ocean. Multiple episodes of tectono-magmatic activities and associated composite orogenic metallogenic systems have also been occurred. However, the tectonic affinities of these composite orogenic metallogenic systems are still not well understood, due to the poor knowledge of the temporal and spatial transitions among the three tectonic domains. Recently, a regional ocean, namely the Heilongjiang Ocean, has been proposed to be a critical link among the three tectonic domains that drove the Paleozoic tectonic evolution of the eastern Central Asian Orogenic Belt. To constrain the tectonic history of the Heilongjiang Ocean, here we reported new petrological, whole-rock major and trace elemental, and zircon U-Pb geochronological data of sedimentary and magmatic rocks from the western edge of the Jiamusi-Khanka Massif in the east of Heilongjiang Province. Integrating our new results with previous studies in the region, we established a novel tectonic framework for the eastern Central Asian Orogenic Belt: (1) During 380–310 Ma, a tectonic switch occurred in the region from weakened influence of the Paleo-Asian Ocean domain in the south to enhanced influence of the westward subduction of the Panthalassa into the eastern Jiamusi-Khanka Massif; the latter induced back-arc extension and eventually the opening of the Heilongjiang Ocean, which drove the Jiamusi-Khanka Massif to drift eastward away from the Central Asian Orogenic Belt; (2) during 300–270 Ma, subduction of the Heilongjiang Ocean was triggered in its eastern margin, producing arc-type magmatism in the west edge of the Jiamusi-Khanka Massif; by 270–210 Ma, subduction of the Heilongjiang Ocean expanded to its west margin (beneath the Songliao Massif); (3) following the eventual closure of the Heilongjiang Ocean in ~ 180 Ma and subduction of the Paleo-Pacific Ocean in the east, the Jiamusi-Khanka Massif rejoined the conterminous Central Asian Orogenic Belt, marking the final amalgamation of the Central Asian Orogenic Belt; since then, the tectonic history of the composite orogenic metallogenic systems in the east of North China was taken over by the Paleo-Pacific domain. This new tectonic model not only links the evolution of the three tectonic domains, but also provides a vital basis for the geodynamic framework of the contemporary endogenetic metallogenesis in this region. [ABSTRACT FROM AUTHOR]

• Granite gneisses from the Xinghuadukou Complex yielded zircon U-Pb ages of 1.84–1.87 Ga. • These granites have I-type, likely formed by partial melting of a thickened crust and subsequently experienced extensive fractional crystallization. • The Xing'an Block in the CAOB was a micro-continental block with Paleoproterozoic basement and originally part of the Columbia supercontinent. The Precambrian evolution of the Central Asian Orogenic Belt (CAOB) in NE China remains enigmatic. The Xinghuadukou Complex, located in the Xing'an Block of NE China, contains important records of the Precambrian geological evolution of the eastern CAOB. In this study, we present petrographic observations, zircon U–Pb ages, and major and trace element data of Precambrian granitic gneisses from the Xinghuadukou Complex. The granitic gneisses are characterized by high SiO 2 (69.62–80.66 wt%) and K 2 O (2.15–3.80 wt%), enrichments in Rb, Th, Ba, and Pb, depletions in Nb, Ta, Sr, Ti, and P, and negative Eu anomalies. These geochemical signatures suggest that the granitic gneisses were derived from high-K, calc-alkaline, I-type granites, which were formed in a volcanic arc setting from magmas involving partial melting of thickened crust and extensive fractional crystallization. A total of 133 zircons in six granitic gneiss samples yielded weighted mean 207Pb/206Pb ages of 1865 ± 10, 1847 ± 13, 1858 ± 12, 1852 ± 9, 1872 ± 9, and 1859 ± 13 Ma, respectively. All the zircons combined define a weighted-mean 207Pb/206Pb age of 1861 ± 4 Ma, indicating a Paleoproterozoic basement in the Xing'an Block. In combination with data from previous studies, we suggest that the Xing'an Block was a microcontinent, likely part of the Columbia supercontinent. [ABSTRACT FROM AUTHOR]

Northeast (NE) China is located in the eastern Central Asian Orogenic Belt (CAOB) and evolved from the amalgamation of several microcontinental blocks, which, from west to east, include the Erguna, Xing'an, Songliao, and Jiamusi-Khanka blocks. Since the Paleozoic, NE China has undergone multiple stages of subduction–accretion and tectonic destruction under the tectonic domains of the Paleo-Asian Ocean, Panthalassa, and the Paleo-Pacific Ocean. This complexity has resulted in uncertainty surrounding the amalgamation processes of the various microcontinents. Fortunately, several suture zones in NE China, including the Toudaoqiao–Xinlin Suture, the Hegenshan–Heihe Suture, the Solonker–Xar Moron–Changchun Suture, and the Jilin–Heilongjiang High-pressure Belt contain information that provides key constraints on the tectonic evolution of NE China. This paper reviews the spatial distribution, composition, and formation ages of these suture zones based on published geological records. Our temporal and spatial analyses of these suture zones enable the evolution of NE China to be assigned to those three tectonic domains: (1) In the earliest of these, the Paleo-Asian Ocean tectonic domain (650–250 Ma), the Erguna Block amalgamated with the Xing'an Block along the Toudaoqiao–Xinlin Suture during the Late Cambrian (ca. 500 Ma); the Erguna–Xing'an Block then collided with the Songliao Block along the Hegenshan–Heihe Suture during the Late Carboniferous (ca. 300 Ma), whilst the combined Erguna–Xing'an–Songliao Block amalgamated with the North China Craton along the Solonker–Xar Moron–Changchun Suture at the End-Permian (ca. 250 Ma). (2) in the Panthalassa tectonic domain (315–230 Ma), the subduction of Panthalassa (or locally, the Mongol-Okhotsk Ocean) was initiated in the eastern Jiamusi-Khanka Block during the Late Carboniferous (ca. 315 Ma), resulting in back-arc extension in the western Jiamusi-Khanka Block, which evolved into the Heilongjiang Ocean separating the Jiamusi-Khanka and Songliao blocks during the Late Permian to Late Triassic (260–230 Ma). (3) in the Paleo-Pacific Ocean tectonic domain (230–130 Ma), the first stage of westward subduction of the Paleo-Pacific oceanic plate occurred during the Late Triassic (ca. 230 Ma), causing the Jiamusi-Khanka Block to amalgamate with the North China Craton during the Late Triassic (ca. 230 Ma) and subsequently with the Songliao Block during the Late Triassic to Early Jurassic (210–180 Ma), forming the Jilin–Heilongjiang High-pressure Belt, whereas the second stage of subduction induced the emplacement of the Nadanhada Terrane during the Early Cretaceous (ca. 130 Ma). This represented the final assembly of NE China in the eastern CAOB. • NE China can be divided into three tectonic domains of the Paleo-Asian Ocean, the Panthalassa, and the Paleo-Pacific Ocean. • The assembly of NE China was accomplished through the generation of five suture zones, which formed from ∼500 Ma to ∼130 Ma. • NE China recorded multiple stages of activity of the Paleo-Asian, Panthalassa (Mongol-Okhotsk), and the Paleo-Pacific oceans. [ABSTRACT FROM AUTHOR]

Hypertension is a kind of chronic cardiovascular system disease caused by a series of factors and carriers dysfunction, which belongs to the category of Tibetan medicine "Chalong disease", and has a high rate of disability and mortality. Zuomua Decoction is a classical Tibetan medicine for Chalong disease, but its mechanism is not clear. Therefore, in this paper we explored the multi-components, multi-targets and multi-channels mechanism of Zuomua Decoction in the treatment of hypertension based on network pharmacology and molecular docking technology. First of all, the chemical components of Zuomua Decoction were obtained in the retrieval of traditional Chinese medicine systems pharmacology database(TCMSP), China National Knowledge Infrastructure(CNKI) and Wanfang database. The potential targets of Zuomua Decoction were predicted by BATMAN-TCM database, and the targets of hypertension were obtained by using DisGeNET database. The intersection of these two targets set was taken to obtain the potential targets of Zuomua Decoction in the treatment of hypertension, and then the chemical compositions-targets network was constructed. Secondly, the intersection targets were imported into STRING database to obtain the interaction relationship of intersection targets, and the protein interaction network of Zuomua Decoction in the treatment of hypertension was constructed in Cytoscape. Topological, GO, and KEGG enrichment analysis were used to construct the key targets-signal pathways-biological processes network diagram and explore the mechanism of Zuomua Decoction in the treatment of hypertension. Finally, the key targets were selected to construct the pharmacodynamic identification models to verify the effect mode of Zomua Decoction in treating hypertension. The results showed that there were 61 chemical components and 90 potential targets in the compounds-targets network. We obtained 21 key targets, 154 signal pathways, and 382 biological processes in topological, GO, and KEGG enrichment analysis of the protein interaction network, and in the comprehensive analysis, it was found that Zuomua Decoction could reduce blood pressure by regulating renin angiotension aldosterone system, balancing the concentration of intracellular calcium and sodium ions and regulating vasoconstriction and relaxation. ACE, AGTR1, and ADRB2 were used as the carriers for molecular docking study on the components of Zuoma Decoction, and the results showed that the chemical components of Zuomua Decoction had a good binding activity with key targets. The purpose of this study is to provide ideas for the in-depth study of Zuoma Decoction in the treatment of hypertension, and provide scientific basis for its clinical rational application.