查看更多>>摘要：Green development answers to the common needs and demands of all humanity, especially the emerging economies like China. Based on the newly constructed Metafrontier-Global-SBM super-efficiency DEA (Data Envelopment Analysis) model, this study measures the green economic growth levels of 286 prefecture-level cities in China from 2003 to 2018 and examines their spatiotemporal evolution charac-teristics and internal influencing mechanisms. The empirical findings highlight that China achieved favor-able green economic growth with the most significant improvement in the northeast and eastern coastal cities. In terms of regional distribution, green economic growth in Shanghai, Guangdong, Heilongjiang, Gansu, and Ningxia was at a higher level, while the Chongqing and Qinghai regions were lagging. Based on the decomposition results of the green economic growth rate; the study argues that "innovation effect" was the primary factor driving growth and "technology-leader-transfer effect" showed a contrary inhibiting effect. This study adds empirical evidence to the facts of green development in Chinese cities and the influencing mechanisms behind it, and has important policy implications for further harmonizing the relationship between resource conservation, environmental protection and economic development, and further promoting green development in China and globally. (c) 2022 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
Laskari, SofiaSoukis, KonstantinosStockli, Daniel F.Lozios, Stylianos...
22页
查看更多>>摘要：In the Attic-Cycladic Crystalline Complex (Aegean Sea, Greece), following early syn-convergence exhumation processes, the extensional tectonics resulted in the extreme denudation of the upper plate, preserved today in a few places. The Cycladic Blueschist Unit (CBU) and the underlying Cycladic Basement and the Basal Units have been exhumed in the footwall of detachment systems, juxtaposed against the Pelagonian-derived hanging wall fragments. Traditional views accept that Amorgos Unit occupies a structurally lower position, correlated to the Basal Unit. This study presents lithostratigraphic and structural data, integrated with detrital zircon MDA, provenance analyses, and (U-Th)/He ages, showing a new investigation of the paleogeographic and structural position of Amorgos in the Cycladic archipelago. The low-grade metamorphosed Amorgos Unit presents a tripartite lithostratigraphy: a basal metaconglomerate, a middle carbonate sequence with shallow-water to pelagic facies, and an Eocene (meta)flysch. An HP/LT metabasite huge block is incorporated within the metaconglomerate either by gravitational movements as an isolated olistolith or tectonic processes as a slice during the early deformation stage. Detrital zircon U-Pb analysis on the meta-siliciclastic deposits revealed that the basal metaconglomerate shows a dominant Ediacaran input with Mid-Permian and Precambrian MDAs for the matrix and the high-grade clasts, respectively. The metaflysch shows Paleozoic affinity (e.g., mainly Pelagoniansourced) and Triassic-Jurassic MDAs. The deformation history of Amorgos includes an early-stage topto-NW thrusting in the retro-wedge setting of the Late Eocene-Oligocene subduction zone and a latestage top-to-SE extensional low- and high-angle normal faulting. Zircon (U-Th)/He ages reveal an Early-Mid Miocene (18-14 Ma) exhumation below ti similar to 200 degrees C. Similarities on lithostratigraphy, structural inventory, exhumation history, and structural position of Amorgos Unit with the Santorini Detachment System Pelagonian hanging wall imply their close spatial relationship. From all the above, we propose that Amorgos belongs to the upper plate of the CBU and is paleogeographically located at the southern Pelagonian margin. (c) 2022 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
查看更多>>摘要：Global Paleoproterozoic orogenic evolution can provide important constraints on the Columbia (Nuna) supercontinent assembly. Zircon U-Pb chronology studies on the northern Tarim reveal that a paleoproterozoic tectono-thermal event was developed, which is related to the assembly of the Columbia supercontinent. However, limited metamorphic investigations have hindered the recognition of Paleoproterozoic orogenic evolution in the northern Tarim, further affecting the understanding of the relationship between Tarim Craton and the Columbia supercontinent. The Xingditage Group in northern Tarim is the result of Paleoproterozoic orogeny which can shed light on the Paleoproterozoic orogenic evolution of the northern Tarim Craton. Our study conducted petrography, zircon U-Pb geochronology, and phase equilibria modeling of metapelitic granulite collected from the Xingditage Group. Petrographic and phase equilibria modeling indicate a clockwise P-T path involving the peak metamorphic stage (M1) at similar to 840 ?/7 kbar, the near-isothermal decompression stage (M2) at similar to 840 ?/3 kbar and followed near-isobaric cooling stage (M3) at similar to 785 ?/2.5 Kbar. The ages of metamorphic zircons in metapelitic granulite range continuously from 1831 +/- 13 Ma to 1782 +/- 16 Ma. Petrographic observation shows almost all zircons grow in quartz and biotite (Bi-2), indicating they were recrystallized during the isobaric cooling stage (M3) after decompression. Thus, the ca. 1.85-1.80 Ga metamorphic age in northern Tarim records a regional post-T(ma)x cooling event after exhumation rather than a collisional event of crustal thickening. We further propose a tectonic evolution scenario of the northern Tarim Paleoproterozoic orogenic belt and suggests the northern Tarim has collided with an unknown block (perhaps Sharyzhalgai uplift in southwestern Siberia Craton) and became a peripheral part of the Columbia supercontinent prior to similar to 1.85 Ga. (C) 2022 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
查看更多>>摘要：The relationship between globalization and environmental quality has drawn intensive attention in recent years. However, few studies have focused on global evidence considering the diverse dimensions of globalization outside of economic globalization. Moreover, evidence on the effects of globalization on environmental quality does not provide clear patterns. This study analytically explores and empirically tests the links of globalization with environmental quality. For empirical analysis, a large panel data of 180 countries is assembled over the period 1980-2016. The empirical results show that globalization helps to ameliorate environmental degradation. Panel quantile regression results also support the favor-able role of globalization mainly for economies with existing low levels of carbon emissions. However, the decomposition of globalization into different domains reveals that this finding cannot be generalized for all dimensions of globalization. In particular, this study finds out robust evidence that economic glob-alization is harmful to environmental sustainability. However, political globalization has been shown as a tool for enhancing environmental quality. Finally, the environmental Kuznets curve is validated in all models. These findings remain consistent with different robustness checks.(c) 2022 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
Avigad, DovAbbo, AvishaiGerdes, AxelSchmitt, Axel K....
18页
查看更多>>摘要：We studied detrital zircon from black sand of the Rhone River delta (southern France) which drains significant parts of Western Europe. Zircon U-Pb geochronology shows that the black sand is an extraordinary sampler of all major episodes of European magmatism peaking at 0.55 Ga (Cadomian), 0.45 Ga (Cenerian) and 0.31 Ga (Variscan). Hf in detrital zircon suggest that European magmatic episodes involved continuous crustal reworking along a crustal evolutionary array with Hf-TDM ages pointing to the reworking of an older, Mesoproterozoic (1.0-1.5 Ga) crustal reservoir. However, the coupling of O isotopes shows that the majority of the zircon possess elevated delta O-18 values indicating the involvement of a noteworthy sedimentary component in the genesis of European granitoids. Therefore, a preponderance of the obtained Hf-T-DM ages are mixed and do not designate the reworking of Mesoproterozoic crust. The Variscan and post-Variscan intervals include also a significant proportion of detrital zircon with mantle-like delta O-18 (< 6.5 parts per thousand) while retaining Mesoproterozoic Hf model ages. Zircon of this type are uncommon in European granitoids and their origin in Rhone delta is therefore not clear, but we tend to interpret the contrasting isotopic signatures as indicating crystallization from juvenile melts whose Hf reflects source contamination. Few ancient, pre-Neoproterozoic continental slivers are scattered in Western Europe, yet our U-Pb-HfO detrital zircon data do not support the widespread reworking of a pre-Neoproterozoic deep crustal reservoir in this region. The prevalent oldest rocks of Western Europe are Late Ediacaran Cadomian clastic sediments, mostly derived from the erosion of Gondwana Pan-African orogens with variable contributions from proximal Cadomian arcs. The apparent Mesoproterozoic Nd and Hf model ages of many European granitoids are likely inherited from the isotopic properties of their Late Ediacaran (and younger) precursor sediments which carry the isotopic composition of the North Gondwana crust. (C) 2022 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
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