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The Gated Recurrent Unit (GRU) neural network has great potential in estimating and predicting a variable. In addition to radar reflectivity (Z), radar echo-top height (ET) is also a good indicator of rainfall rate (R). In this study, we propose a new method, GRU_Z-ET, by introducing Z and ET as two independent variables into the GRU neural network to conduct the quantitative single-polarization radar precipitation estimation. The performance of GRU_Z-ET is compared with that of the other three methods in three heavy rainfall cases in China during 2018, namely, the traditional Z-R relationship (Z=300R1.4), the optimal Z-R relationship (Z=79R1.68) and the GRU neural network with only Z as the independent input variable (GRU_Z). The results indicate that the GRU_Z-ET performs the best, while the traditional Z-R relationship performs the worst. The performances of the rest two methods are similar. To further evaluate the performance of the GRU_Z-ET, 200 rainfall events with 21882 total samples during May–July of 2018 are used for statistical analysis. Results demonstrate that the spatial correlation coefficients, threat scores and probability of detection between the observed and estimated precipitation are the largest for the GRU_Z-ET and the smallest for the traditional Z-R relationship, and the root mean square error is just the opposite. In addition, these statistics of GRU_Z are similar to those of optimal Z-R relationship. Thus, it can be concluded that the performance of the GRU_Z-ET is the best in the four methods for the quantitative precipitation estimation. [ABSTRACT FROM AUTHOR]

Olivine grains from Songshugou mylonitized peridotite massif record δ18O both lower and higher than in pristine mantle samples in North Qinling Orogen, Central China. Olivines from dunites exhibit large variations in δ18O (4.03–7.07‰), and some porphyroclasts display negative correlations between δ18O and forsterite content {Fo; [100×Mg/(Mg+Fe2+)]}. The porphyroclast cores have low-δ18O values, indicating that they formed in the oceanic lithospheric mantle prior to subduction. We attribute low-δ18O values to seawater-peridotite interaction under high-temperature conditions. The porphyroclast rims and small olivines exhibit high-δ18O values. These features suggest that high-δ18O olivines formed during mylonitization in the exhumation process. Olivines reacted with 18O-rich melt/fluids released from subducted altered oceanic basalts and continental sediments at low temperature (<610–680 °C). The 18O-rich melt/fluids selectively affected porphyroclast rims and small olivine grains. Unlike the olivines in the dunites, the olivines and orthopyroxenes in the harzburgites show limited variations in δ18O (4.21–5.45‰ and 5.5–5.8‰, respectively), due to orthopyroxene exchange with melt/fluid at a slower rate than the coexisting olivine. The preservation of the low-δ18O signature in olivines indicates a short residence time (<20 Ma) for subducting peridotites to mantle depths. [ABSTRACT FROM AUTHOR]

With the 1 h-averaged data of atmospheric precipitable water vapor (PWV) for 2015–2018 retrieved from 18 ground-based Global Positioning System (GPS) observation stations near Poyang Lake (PL), China, the diurnal variations of the PWV during midsummer (July-August) are studied by the harmonic method. Results show that significant diurnal variations of PWV are found at the 18 GPS stations. The harmonics with 24 h cycle (diurnal cycle) over PL (i.e., Duchang and Poyang) and Nanchang city only have about 50% (or even smaller than 50%) of variance contribution with the amplitude of about 0.2 mm, while above 70% (or even 80%) of variance contribution occurs elsewhere around PL, with the amplitude of about 0.9 mm. The harmonics with diurnal cycles in most stations peak from afternoon to evening (i.e., 1200-2000 LST), but one exception is Duchang site, where the diurnal cycle peaks in the morning (i.e., 1000 LST). Moreover, the harmonics with 12 h cycle (semidiurnal cycle) have the relatively uniform amplitude of about 0.2 mm, but their variance contributions show uneven distribution, with the contributions of about or above 50% in PL and Nanchang city (the semidiurnal cycles peak about 0000 LST or 1200 LST) and below 30% (or even 10%) in other areas. The preliminary diagnosis analysis shows that the diurnal variation of the low-level (below 850 hPa) air temperature (increasing after the sunrise, decreasing after the sunset, and peaking around 1400-1800 LST) may be responsible for the diurnal cycle. Moreover, in PL (Duchang and Poyang) and Nanchang city, the effects (heating or cooling) of lake and urban, the diurnal variation of the 10 m wind over PL, and the acceleration of PL on overlying air also contributed to the diurnal variation of PWV. [ABSTRACT FROM AUTHOR]

A method named BTREC, which is in fact an extension of tracking a radar echo by cross-correlation (TREC) method, is proposed based on the Barnes filter in this paper. BTREC is an efficient objective analysis method for smoothing the motion vectors of radar echo patterns. A comparative analysis of the BTREC vectors and the COTREC (another extension of TREC, which is restricted by the 2D continuity equation) vectors is conducted. The results show that the BTREC method corrects the noise and inconsistencies in TREC vectors (often induced by shielding, ground clutter, and rapid morphological changes of the radar patterns) more thoroughly than COTREC. Then the BTREC, COTREC, and TREC methods are applied to extrapolate the real radar echo pattern over Jiangxi Province in China for two cases (1900–2100 UTC 4 June and 0900–1100 UTC 30 June 2018). Results show that the BTREC method performs the best out of the three methods to forecast the radar echo patterns in the following 1 and 2 h, and has the least distortion. To further confirm that, 892 radar composite reflectivity mosaic images with precipitation in summer (June–August) over Jiangxi are collected to test the three methods. The results show that in the 1- and 2-h extrapolations, the mean differences of the threat score (TS), correlation (CORR), and probability of detection (POD) between BTREC and TREC are obviously more than 0, while that of the false alarm ratio (FAR) is remarkably less than 0 (the threshold to identify whether a grid is correctly predicted is set to 10 dBZ). Although the mean difference of TS, CORR, POD, and FAR between COTREC and TREC have similar variation, their magnitudes are obviously decreased (especially for the 2-h extrapolation). This further indicates that the BTREC method obviously improves the forecast of the radar echo pattern within the next 2 h compared to the COTREC and TREC methods. [ABSTRACT FROM AUTHOR]

Four experiments, uniform experiment (UF) with a constant lake surface temperature (LST), spatial experiment (SP) with the space change of LST, temporal experiment (TM) with the time change of LST and spatiotemporal experiment (SP-TM) with the space and time changes of LST, were performed to explore the response of a convection over Poyang Lake (PL) in China on 12–13 August 2015 to the time and space variations of LST based on the Weather Research and Forecasting (WRF) model. Simulation results show that the spatiotemporal variation of LST significantly affects the convection. Compared with the observation, the UF and SP simulated convection advances about 3 h, with greater coverage and a more southerly location, while the TM simulated convection also advances about 3 h, with smaller coverage. The SP-TM simulated convection is well consistent with the observation in time evolution, coverage, location and intensity, improving the simulation of the convection greatly. The diagnostic analysis shows that the time and space variations of LST in PL change the atmospheric stability and low-level uplift movement by adjusting low-level air temperature, humidity and wind over PL and its nearby areas, finally affecting the development of the convection. The fact that convection, atmospheric stability and near-surface wind over the lake are sensitive to the spatiotemporal variation of LST strongly suggests the need to monitor and forecast the distribution and time evolution of LST for accurate prediction of convection over PL. • Four experiments are performed to explore the response of a convection over Poyang Lake on lake surface temperature (LST). • The spatiotemporal variation of LST can significantly affect the initiation, location and intensity of the convection. • After considering the time and space changes of LST, the model improves the simulation of the convection obviously. • The spatiotemporal variation of LST affects the convection through regulating the near surface wind, LFC and CAPE. [ABSTRACT FROM AUTHOR]

Two types of Cenozoic lavas composed of high magnesium andesites (HMAs) and high-K basalts (HKBs) occur in the northern Songliao Basin (NSB), Northeastern China. This study presents K-Ar geochronology, olivine phenocryst compositions, whole-rock major and trace element, and Sr-Nd-Pb-Hf isotopic compositions of HMAs from Menluhe and Xunke in NSB, and discuss the origin of high Nb/Ta signature and mantle source heterogeneity of these lavas. The HMAs from Menluhe and Xunke erupted between 0.20 and 1.72 Ma. These andesitic lavas display negative ε Nd (−3.2 ∼ −10.4) and ε Hf (−3.3 ∼ −19.3), elevated 87Sr/86Sr (0.7048–0.7061), and unradiogenic Pb isotopes (206Pb/204Pb = 16.50–17.10), similar to those of the high potassium basalts (HKBs) in Keluo-Wudalianchi-Erkeshan near the HMA fields. Within the HMAs, the olivine phenocrysts have high Ni contents and elevated Fe/Mn (69.1–93.9, average 78.1) compositions. The petrology index FCKANTMS (Yang et al., 2019) values range from 0.57 to 0.75. Both the olivine compositions and the petrology index support a pyroxene source. Enrichments in large ion lithophile elements (Ba, K and Sr) and depletions in high field-strength elements (Nb, Ta, Th and U), with anomalously high Nb/Ta ratios (18.9–22.6) in the andesite, are consistent with a combined metasomatism of carbonatite and silicate melts to the lithospheric mantle. HMAs tend to occur in rift basins, while HKBs tend to occur in off-rift zones, suggesting a close magmatic-tectonic correlation. Metasomatism (by carbonatite and silicate melts) and rifting may form a positive feedback mechanism, resulting in coupled HMAs, HKBs and rifts in NSB. • Carbonatite-rich and silicate-rich melts contribute to the lithospheric mantle origin of the high Mg andesites. • Carbonatite-rich melts may be an agent delivering the high Nb/Ta and EM1 signatures. • The HMAs and HKBs volcanism in the Northern Songliao Basin occur as a result of on-going lithosphere extension and thinning. [ABSTRACT FROM AUTHOR]

Abstract: The Changbaishan (Tianchi) volcano extending across the border of northeast China and North Korea erupted ~100km3 peralkaline rhyolites around 1000AD. This Millennium eruption of the Changbaishan volcano is one of the two largest explosive eruptions in the past 2000years. Here we report the results of uranium–thorium dating of zircons from the Changbaishan volcanic rocks. Our data indicate that the rhyolitic magmas were stored in the crust for only 8.2±1.2ka prior to eruption. Based on titanium-in-zircon geothermometer and alkali feldspar-glass geothermometer, the rhyolitic magmas were formed at a relatively low temperature (~740±40°C). This storage time is very short compared with other large volume catastrophic silicic eruptions. This work demonstrates that peralkaline rhyolitic magmas from the Changbaishan volcano can develop into a catastrophic eruptive phase quite quickly. [ABSTRACT FROM AUTHOR]

Abstract: Throughout the Cenozoic, post-collisional potassic volcanism has been widespread in the Tibetan Plateau, but Holocene (<10ka) volcanism is rare and has only been reported from three volcanoes near Tengchong (Yunnan Province, China) within the southeastern Tibetan Plateau. Some of the Holocene volcanic rocks are differentiated lavas with SiO2 contents of 58wt.% and contain zircon crystals. These zircon-bearing differentiated lavas provide a unique opportunity for studying magma chamber processes in an environment of thickened continental crust by using short-lived uranium–thorium (U–Th) isotopes. Here we report U–Th zircon ages from Maanshan volcano (one of the three Holocene volcanoes from Tengchong) measured by secondary ion mass spectrometry ion microprobe (SIMS) techniques. A novel part of the zircon U–Th dating is the use of shallow depth profiling of the outermost rims and its comparison to traditional “core & rim” spot analyses. The U–Th ages of zircon interiors from Maanshan volcano show bi-modal distributions. The zircon interiors from Maanshan yield an apparent U–Th isochron age of 83.5−9.0 +9.8 ka (2 sigma), with a mean square of weighted deviates (MSWD) of 5.1 that is outside the 95% confidence interval expected for a single age population. Based on mixture modeling of zircon age data, the Maanshan zircons may represent a bi-modal population with ages of 55±7ka and 91±6ka in proportions of 23% and 77%, respectively. SIMS shallow depth profiling of unpolished euhedral zircon outermost rims yield a U–Th isochron age of 53.6−5.0 +5.3 ka (MSWD of 0.92). Thus depth profiling of unpolished zircon grains to discern the age of the outermost rims is consistent with the younger of the two peaks on the bi-modal distribution. The older ∼91ka peak represents remobilized zircon antecrysts derived from an earlier episode of andesitic magmatism. The younger 55ka peak represents zircon phenocrysts that grew in the eruptible magma body itself in the build-up to the eruption. The zircon storage time in the eruptible magma body beneath Tengchong is thus about 45ka. Almost comparable temperatures and compositions between cores and rims indicate closed system evolution, rather than polybaric crystallization. [Copyright &y& Elsevier]

Abstract: Extensive (about 5000km3) basaltic magmas erupted on the Hainan Island, south China, mostly during the past 1millionyears. U–Th disequilibrium data as well as Nd, Sr, Pb isotopes and major and trace element concentrations were measured on the youngest lavas from Maanling volcano and Leihuling volcano of the Hainan Island. All the Holocene Hainan basalts display light rare earth element (LREE) enriched patterns and ocean island basalt (OIB)-type incompatible element distributions. Their ε Nd values range from +4.1 to +4.8, 87Sr/86Sr ratios vary from 0.7039 to 0.7042, and 206Pb/204Pb ratios range from 18.63 to 18.71. The Hainan lavas are characterized by their depleted Sr–Nd isotopic compositions and Dupal-like EM2 (enriched mantle 2) Pb isotope signatures with time-integrated high Th/U and 235U/Pb. The olivine tholeiites from Maanling display 18–20% 230Th excesses and the alkali olivine basalts from Leihuling show 22–32% 230Th excesses. The pronounced 230Th excesses in the Holocene basalts indicate that the Holocene Hainan lavas were produced by melting of a mantle source in the garnet stability field (>75km). Since the lithosphere thickness beneath the Hainan Island is thin (55km), the garnet peridotite mantle source for the Hainan basalts is not located in the lithospheric mantle. The Nd isotopic compositions do not indicate a highly depleted asthenospheric mantle source. We thus suggest that the EM2 mantle source for the young Hainan basalts is in the mantle transition zone or more likely lower mantle, which is consistent with a plume origin. The significant 230Th excesses also suggest slow (<1cm/year) upwelling, possibly indicative of a weakly buoyant mantle plume. The older EM2 Cenozoic basalts from Hainan, South China Sea Basin and adjacent areas may also originate from partial melting of lower mantle materials in the rising Hainan plume. [Copyright &y& Elsevier]

The Yandangshan syenite is a representative Late Cretaceous igneous pluton cropping out in SE China. U-Pb zircon dating using LA-ICP-MS yielded a crystallization age of 98±1 Ma for the syenite. Petrographically and geochemically of shoshonitic affinity, it is enriched in LREE and LILE, and has a pronounced Nb-Ta trough in the primitive mantle-normalized trace element spider diagram. Zircon εHf(t) values vary from -3.04 to -7.71, displaying a unimodal distribution. The syenite also has high Sr [(87Sr/86Sr) i = 0.7086-0.7089], low Nd [εNd(t) = -6.57 to -7.64] isotopic ratios, plotting in the enriched mantle field on an εNd(t) versus (87Sr/86Sr) i diagram. We propose that the Yandangshan syenite was generated by pyroxene-dominated high-pressure fractional crystallization from basaltic magma that was derived from an enriched mantle source. Although coexisting Yandangshan rhyolites have Sr-Nd isotopic compositions similar to the Yandangshan syenite, they were not derived from the same source. Instead, the rhyolitic magma was produced by partial melting of crustal materials as a result of the underplating of basaltic magma. The crust-like Sr-Nd-Hf isotopic signature of the Yandangshan syenite is ascribed to mantle sources that were enriched by subducted sediments. Formation of Yandangshan syenite may represent roll-back of the subducting palaeo-Pacific plate and migration of the arc front to the Yandangshan area at ∼98 Ma. [ABSTRACT FROM AUTHOR]

Abstract: Young (300 to 5500years old) dispersed intraplate volcanism characterized by small volume of melt and large compositional variability, occurred over NE China at Jingbohu, Long-gang, Tianchi and Wudalianchi. These young volcanic rocks provide ideal opportunities for investigating the mechanism of dispersed continental volcanism using short-lived uranium-series isotopes. We present systematic U-series, Nd, Sr, Pb isotope and trace element analyses of the young lavas from NE China. Jingbohu lavas display variable extents of 230Th excesses (10 to 28%) and moderately depleted Nd isotopic compositions (ε Nd = + 1.5 to + 3.3). Long-gang lavas have pronounced (33 to 35%) 230Th excesses and slightly depleted Nd isotopic compositions (ε Nd = + 0.5 to + 0.7). The Tianchi lavas display moderate (12%) 230Th excesses and slightly enriched Nd isotopic compositions (ε Nd = − 1.0 to − 1.1). 230Th enrichments in all these volcanic rocks are uncharacteristic of melts generated by subduction. The strongest evidence against the involvement of subduction-related fluids is derived from the Long-gang lavas having more than 30% 230Th excesses, low U/Th, Sr/Th and Ba/Th ratios, and positive Nb and Ta anomalies. The fluids released from the subduction of the Pacific plate under the Eurasian plate might have already been completely lost before the slab reached the mantle beneath NE China. We postulate that, in addition to the convective circulation process, the continuous piling up and upward thickening of stagnant Pacific slab in the mantle transition zone may help drive a broad asthenosphere upwelling far from the trench, leading to mantle partial melting and the formation of the young volcanoes in NE China. In addition, our U–Th disequilibrium data provide constraints on magma evolution time. The magma evolution time from low SiO2 (47.5%) basalt to higher SiO2 (50.4%) basalt at Long-gang is within 10 thousand years (10ka). The magma evolution time from trachyte to rhyolite at Tianchi volcano is also less than 10ka. If the Tianchi silicic rocks were evolved from Long-gang basaltic magmas with minor crustal assimilation, then the magma evolution time from basaltic magma to silicic magmas is less than 110 thousand years. [Copyright &y& Elsevier]

The only historic eruptions of potassic basalts on the Earth reported so far took place in 1719–1721 AD in the Wudalianchi area of northeast China. These historic potassic basalts are characterized by significant 230Th excesses [(230Th/238U)=1.24–1.33], and low 143Nd/144Nd (&epsiv;Nd=−5.0 to −3.7) and 206Pb/204Pb (16.8–17.1). Strong 230Th excesses, low CaO+Al2O3, and large bulk partition coefficients (D) in Rb, K, and Zr (DRb(DK>DZr>DYb>DSm) inferred from a melt-normalized spider diagram suggest phlogopite-bearing garnet peridotites as dominant source rocks. The presence of garnet peridotites as mantle source, combined with negative &epsiv;Nd in basalts and the geophysically determined lithosphere thickness in the study region (120 km), indicates the generation of these basalts at the depth of 80–120 km in the subcontinental lithospheric mantle. Dynamic melting inversion (DMI) of between-magma trace element concentration ratios and U–Th disequilibrium data suggests low-degree partial melting (5–7%) of a slow upwelling (<1.6 cm/year) mantle source, although extremely low-degree batch partial melting (0.3–0.5%) of a static source is also possible. Source Nd model ages suggest that the source rocks for the Wudalianchi basalts were metasomatized at 1.0 Ga, provided that it has not experienced multistage enrichment history. Lithospheric extension since late Tertiary in the study region was responsible for slow decompression melting of phlogopite-bearing garnet peridotites in deep subcontinental lithospheric mantle. Recent (<350 ka) subduction of the Pacific Plate may have produced lithospheric extension in the study region, but did not directly contribute subduction-related fluids to the source rocks for these potassic basalts because 230Th enrichments are uncharacteristic of melts generated by subduction. The subducted slab may have lost fluids released from subducted sediments before the slab can reach the mantle beneath NE China. [Copyright &y& Elsevier]

The Tengchong volcanic field in southwestern China represents rare Quaternary volcanic eruptions and associated active geothermal activities on the southeastern margin of the Tibetan plateau. The reported eruption ages for the 3 youngest Tengchong volcanoes (Heikongshan, Dayingshan, Maanshan) are highly variable (3.0–482 ka) because of the challenge to accurately and precisely date young volcanic rocks by radiometric methods. Here we use high-resolution 238U-230Th-226Ra disequilibria to constrain the eruption ages and magma evolution timescales. All 3 young volcanoes exhibit whole-rock (226Ra/230Th) disequilibrium ranging from 1.27 to 1.71, indicating eruption ages of <8 ka (5 half-lives of 226Ra). Eruption ages of 2.9–5.1 ka for Heikongshan, 3.3–4.0 ka for Dayingshan, and 2.9–3.6 ka for Maanshan are constrained by (226Ra/230Th) evolution models. This study thus suggests Holocene eruptions for all 3 volcanoes and represents the first Holocene radiometric age for Dayingshan. We also measured 238U 230Th ages of zircons from Heikongshan, Dayingshan, and Maanshan. Zircon age populations are 54.6 ± 13 ka and 94.9 ± 4.1 ka for Heikongshan, 59.6 ± 5.8 and 90.1 ± 8.4 for Dayingshan, and 53.8 ± 8.7 ka and 76.5 ± 11 ka for Maanshan. Magma residence times for all 3 volcanoes are ~50 kyr for a shallow stage and 85 kyr for a deep stage in a two-stage magma chamber system below Tengchong. The similar zircon age distributions for the 3 volcanoes from Tengchong indicate simultaneous magmatism at 90 ka and 55 ka and imply interconnected nature of these volcanoes. • We report bulk Ra Th isotope and zircon U Th isotope data for Tengchong volcanoes. • Ra Th isotopes indicate 3 Tengchong volcanoes are Holocene volcanoes. • We obtain zircon age pulses of ~55 ka and ~90 ka for these 3 volcanoes. • The magma chambers for Heikongshan, Dayingshan, and Maanshan are interconnected. • Magma residence time is 50 kyr for a shallow magma chamber and 85 kyr for a deep one. [ABSTRACT FROM AUTHOR]

Abstract: Zircon U–Pb and Hf isotope compositions have been systematically measured to constrain the timing and petrogenesis of the Late Mesozoic volcanic sequences in southeastern Zhejiang, SE China. The Early Yanshanian (Jurassic) volcanism took place at 177Ma and formed scattered volcanic rocks in the region. In contrast, the large-scale Late Yanshanian (Cretaceous) volcanism, with multiple eruptive stages between 140 and 88Ma, formed the widespread lower and upper volcanic series. Two volcanic hiatuses were clearly identified at 120–110Ma between the lower and upper volcanic series and at 128–122Ma between the two subdivided cycles within the lower series. In addition, the magnitude of the two volcanic cycles in the lower series is significantly different. The cycle I of the lower series (140–128Ma) occurred in the largest scale, which is much larger than the cycle II (122–120Ma) as well as the whole upper series (110–88Ma). Petrogenetically, the widespread Late Mesozoic volcanic rocks were mainly derived from the partial melting of the Paleoproterozoic crustal basement materials, with obvious addition of juvenile materials after 122Ma. The analyzed zircons of the Early Yanshanian volcanic rocks show crustal model ages (T DM2) mainly of 2.00–2.16Ga, and weighted mean ε Hf(t) value of −13.4. The ε Hf(t) and T DM2 values are ca. −10 and 1.67–2.00Ga for zircons from the cycle I volcanic rocks, −11.4 to −1.4 and 1.27–1.90Ga for those from the cycle II volcanic rocks, −9.3 to −2.7 and 1.33–1.78Ga for those from the acidic rocks of the upper series, respectively. The characteristics of the Late Mesozoic volcanic sequences indicate the varying influence of the subduction of the paleo-Pacific plate. Our study supports that the subduction style changed from low-angle to intermediate-angle forward subduction at the first hiatus of 128–122Ma and then dramatically changed to rapid high-angle rollback subduction at the second hiatus of 120–110Ma. [Copyright &y& Elsevier]

Neoproterozoic layered mafic intrusions occur along the northern margin of the Yangtze Block in South China. In this paper, we report the chemical compositions of clinopyroxene, plagioclase, and olivine from two major mafic intrusions at Bijigou (BJG) and Wangjiangshan (WJS), to constrain the parental magma characteristics and geodynamic setting. The olivine and plagioclase compositions indicate that the parental magma for BJG and WJS was an evolved tholeiitic magma with high FeO T /MgO ratios. An origin of arc magmatism is not supported by the following mineralogical and petrological observations: (1) the strong rift-affinity indicated by olivine, plagioclase and clinopyroxene geochemistry, (2) the absence of high anorthite in the cumulate rocks, (3) the paucity of abundant cumulus hornblende crystals, and (4) the lack of voluminous intermediate rocks in the rock associations. We propose that the BJG and WJS mafic-ultramafic intrusions formed under a rift extensional setting during 820–780 Ma. The subduction process ceased before 820 Ma and did not directly contribute to the generation of the BJG and WJS mafic-ultramafic intrusions. The arc-like Nb Ta depleted trace element pattern in the parental magma is inherited from the mantle metasomatized by earlier subduction processes. • The parental magma was evolved tholeiitic magma with an arc-like Nb-depleted nature. • Mineral chemistry and petrology suggest a rift extensional setting during 820–780 Ma. • The arc nature in the parental magma is inherited from earlier subduction processes. • The tectonic regime had changed from compression to extension prior to 820 Ma. [ABSTRACT FROM AUTHOR]

[Display omitted] • 954, 929–841 Ma igeneou rocks formed Precambrian basement of Songliao Block. • Songliao Block experienced a collision event before 954 Ma. • Advancing subduction occurred at 0.95–0.85 Ga along blocks in NE China. • Retreating subduction scince 0.85 Ga led to subsequent rifting of these blocks. • Blocks in NE China recorded assembly and breakup of Rodinia. As the core of NE China blocks (i.e., Songliao, Jiamusi-Khanka, Erguna, Xing'an), the Songliao Block plays an important role in understanding the Precambrian evolutionary history of the eastern Central Asian Orogenic Belt (CAOB), as well as the linkage with reconstructions of Rodinia supercontinent. In this work, we present sedimentological, whole-rock geochemical, and zircon U–Pb–Hf isotopic data for the Neoproterozoic-early Cambrian igneous and sedimentary rocks in eastern Songliao Block. The newly identified 954 ± 2 Ma gneissic syenogranite pluton，916 ± 5 Ma meta -basaltic andesite, and the reported 929–841 Ma intrusive rocks formed the Precambrian crystalline basement of the eastern Songliao Block, which was overlain by the late early Neoproterozoic to early Cambrian stable sedimentary cover. The early Neoproterozoic (954 Ma) gneissic syenogranite was likely the product of muscovite dehydration melting of sedimentary rocks in deep crust during the post-collisional setting, probably associated with the collision between the Songliao and Jiamusi-Khanka blocks. The late Neoproterozoic to early Cambrian Chenming Formation displays characteristics of passive margin deposition, which formed after the opening of Paleo-Mudanjiang Ocean at 777 Ma. Integration of the spatial and temporal distributions of Neoproterozoic magmatism and sedimentation in the Songliao, Erguna, Xing'an and Jiamusi-Khanka blocks, as well as the geochemical variations from 0.96 to 0.73 Ga, we suggest that the blocks in NE China have experienced a similar two-stage Neoproterozoic tectonic evolutionary history associated with the Rodinia assembly and breakup. An early advancing subduction along peripheral Rodinia led to the collision and collapse extension between the Songliao and Jiamusi-Khanka blocks before 954 Ma, and the generation of 929–880 Ma syenites and granitoids in compressional continental arc setting. Then the retreating subduction formed the 850–737 Ma mafic and felsic rocks in Songliao, Erguna and Jiamusi-Khanka blocks, and caused breakup of the joint continent and opening of the Paleo-Mudanjiang and Paleo-Xinlin oceans, two branches of Paleo-Asian Ocean, since 777 Ma. In response to the oceanic spreading, the passive continental margin sedimentation developed in these blocks during 750–520 Ma. [ABSTRACT FROM AUTHOR]