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Cenozoic volcanic rocks in the East Asian continental margin usually form because of asthenosphere upwelling and resultant decompression melting, and their origins are important in deciphering mantle geodynamics attributed to intraplate volcanism. In this study, Oligocene basanite‐tephrite rocks were found in continental interior outcrops, and Miocene to Pliocene basanite, alkaline basalt, and olivine tholeiite were abundant in coastal areas in Zhejiang, Southeast China. Episodic magmatic activities appeared to migrate oceanward with an ∼100‐km spatial gap, which was temporally and spatially synchronized with repeated retreat and rollback of the Tertiary westward subducting Pacific slab. All rocks had OIB‐like trace‐element patterns, but the basanite‐tephrite rocks contained higher LILE, HFSE, and LREE than the alkaline basalt and olivine tholeiite. Geochemical modeling indicated the basanite‐tephrite and the alkaline and olivine tholeiite basalts had low‐degree (7%–15%) and slightly higher degree (20%–30%) partial melting of heterogeneous pyroxenite sources, respectively. In addition, their magma sources showed a progressive weakening of carbonatite metasomatism and decreasing melting depths. Those features were tightly associated with punctuated upwelling of asthenospheric materials, most likely metasomatized by the stagnant Pacific slab‐derived silica/carbonatite melts. A plate‐mantle convection system is proposed in which asthenosphere materials pulled by the subducting Pacific slab explain the intraplate volcanism in East Asia as asthenospheric upwelling, which formed by escaping from either slab tears or slab front edges in the mantle transition zone. Plain Language Summary: Oligocene basanite‐tephrite rocks were found in the continental interior, whereas Miocene to Pliocene basanite, alkaline basalt, and olivine tholeiite were abundant in coastal areas in Zhejiang, Southeast China. Episodic magmatic activities appeared to migrate oceanward with ∼100‐km spatial gap, which was temporally and spatially synchronized with repeated retreat and rollback of the Tertiary westward subducting Pacific slab. A plate‐mantle convection system indicates that asthenosphere materials pulled by the subducting Pacific slab can explain the intraplate volcanism in East Asia as the asthenospheric upwelling, which formed by escaping from either slab tears or slab front edges in the mantle transition zone. Key Points: Oligocene‐Pliocene magmatic activities appeared to migrate oceanward with a ∼100‐km spatial gapSpatial‐temporal synchronization occurred with repeated retreat and rollback of the subducting Pacific slabA plate‐mantle convection system is proposed for the West Pacific and East Asia [ABSTRACT FROM AUTHOR]

In situ zircon U–Pb ages, whole-rock major and trace elements, and Sr–Nd isotopic compositions of the Sucun, Yunfeng, and Jingning intrusions from southwest Zhejiang, NE South China Block, are presented to trace their petrogenesis and shed light on its lithosphere evolution. LA–ICP–MS U–Pb zircon dating shows that the Sucun quartz monzonite and Jingning monzogranite were emplaced at ~135 Ma, and the Yunfeng quartz monzonite and Jingning granite were emplaced at 104 and 112 Ma, respectively. All these intrusions are metaluminous to weakly peraluminous and lie within high-K calc-alkaline to shoshonite series field (SiO 2  = 66–76 wt%, A/CNK = 0.95–1.09, K 2 O/Na 2 O = 0.78–1.77). The Yunfeng quartz monzonite clearly have lower K 2 O and total REE contents, and higher CaO, Na 2 O, Al 2 O 3 , P 2 O 5 , MgO, and TiO 2 contents, and relatively less enriched Sr–Nd isotopic compositions than those of the Sucun quartz monzonite, indicating that the Yunfeng quartz monzonite were derived from partial melting of a more juvenile lower crust sources compared with the magma source of the Sucun quartz monzonite. The Jingning monzogranite exhibit similar major elements covariations and Nd isotopic compositions, but higher Ba, Sr, and Eu contents and lower Rb, Th, and U contents than those of the Jingning granite. The geochemical features imply that the Jingning monzogranite and granite were fluid-present and fluid-absent anatexis products of the same Paleoproterozoic crustal source, respectively. Whole-rock Sr–Nd isotopic data imply that the estimated amounts of juvenile mantle-derived melts input into the mature crust show southeastward decreasing trend away from the Jiangshan–Shaoxing fault. We propose that roll-back and retreat of the Paleo-Pacific subducting plate might cause extensive asthenosphere mantle upwelling in East China, and the mantle-derived melts tend to rise through the regional main fault zones and preferentially modify the lithosphere nearby these faults. [ABSTRACT FROM AUTHOR]

This study assessed the techno-economic feasibility of a biorefinery for valuable by-products (mainly hydrogen, ethanol and fertilizer) generation from food waste. The plant was designed to be built in Zhejiang province (China) with a processing capacity of 100 t food waste per day. It was found that the total capital investment (TCI) and annual operation cost (AOC) of the plant were US$ 7625549 and US$ 2432290.7 year−1, respectively. After the tax, US$ 3141867.6 year−1 of net profit could be reached. The payback period (PBP) was 3.5 years at a 7% discount rate. The internal rate of return (IRR) and return on investment (ROI) were 45.54% and 43.88%, respectively. Shutdown condition could happen with the feed of food waste less than 7.84 t day−1 (2587.2 t year−1) for the plant. This work was beneficial for attracting interests and even investment for valuable by-products generation from food waste in large scale. [Display omitted] • A biorefinery applying food waste for valuable products generation was assessed. • The plant was designed with a processing capacity of 100 t food waste per day. • The hydrogen price was the greatest role affecting the economic performance. • The plant would shutdown with food waste feed less than 7.84 t/d. [ABSTRACT FROM AUTHOR]