Global deep‐time plate motion models have traditionally followed a classical rigid plate approach, even though plate deformation is known to be significant. Here we present a global Mesozoic–Cenozoic ...deforming plate motion model that captures the progressive extension of all continental margins since the initiation of rifting within Pangea at ~240 Ma. The model also includes major failed continental rifts and compressional deformation along collision zones. The outlines and timing of regional deformation episodes are reconstructed from a wealth of published regional tectonic models and associated geological and geophysical data. We reconstruct absolute plate motions in a mantle reference frame with a joint global inversion using hot spot tracks for the last 80 million years and minimizing global trench migration velocities and net lithospheric rotation. In our optimized model, net rotation is consistently below 0.2°/Myr, and trench migration scatter is substantially reduced. Distributed plate deformation reaches a Mesozoic peak of 30 × 106 km2 in the Late Jurassic (~160–155 Ma), driven by a vast network of rift systems. After a mid‐Cretaceous drop in deformation, it reaches a high of 48 x 106 km2 in the Late Eocene (~35 Ma), driven by the progressive growth of plate collisions and the formation of new rift systems. About a third of the continental crustal area has been deformed since 240 Ma, partitioned roughly into 65% extension and 35% compression. This community plate model provides a framework for building detailed regional deforming plate networks and form a constraint for models of basin evolution and the plate‐mantle system.
Key Points
We present a plate motion model including distributed deformation from the Triassic to the present
The model includes most major rifts and orogens formed since the breakup of the supercontinent Pangea
Our optimized mantle reference frame minimizes trench migration and net rotation
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The timing of events during the tectonic evolution of the North China Craton (NCC) and the east China region is debated. Extension, compression, transpression, and shearing occurred throughout the ...NCC since ~320Ma. These main structural stages and the temporal evolution of the structural framework and kinematics are summarized. We present here data from multiple structural and magmatic stages related to temporally varying kinematics and deformation mechanisms during the evolution of the post-cratonization of the NCC. The timing of each stage is constrained using isotopic dating, along with the timing of magmatic intrusion, dyke intrusion, and basin formation associated with tectonic transformation of the NCC. Age data indicate distinct structural and magmatic stages at ~1600–1500, 1300–1100, 445–315, 270–200, 170–155, 130-–110, 75–65, and 25–20Ma, relating to basin formation and continental uplift or collapse. These stages define the tectonic evolution and structural transformation of the NCC and associated de-rooting, reactivation, reworking, and orogenic growth. The tectonic setting and movement direction of adjacent plates changed multiple times during the various stages. The stages are as follows: separation of the NCC from the Gondwana supercontinent and northwards drift; formation of the Central Asian orogenic belt (CAOB) and northwards subduction of the Yangtze plate, resulting in closure of the Qinling Ocean; the rapid initial formation of the western Pacific plate and subsequent subduction; and final closure of the Mongol–Okhotsk Ocean, combined with closure of the Bangong–Nujiang Suture Zone and southwards movement of the Siberian continent, as well as thinning of the North China cratonic lithosphere. Moreover, temporal and spatial changes in deformation, magmatism, and basin formation, as well as kinematic and mechanical transformations, occurred in response to the changing tectonic setting and movement direction of surrounding plates. These various factors resulted in a complex structural evolution of the NCC since 1.8Ga.
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•The main structural stages and the temporal evolution and kinematics of the NCC are summarized.•The decratonization is associated with de-rooting, reactivation, reworking, and orogenic growth.•Temporal and spatial changes in kinematic and mechanical transformations, occurred in response to the changing tectonic setting and surrounding plates.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•First literature review paper of blockchain technology in agri-food value chain management.•Four applications of blockchain technology are identified.•Six challenges for applying blockchain ...technology are identified.•Research gaps and future research directions are proposed.
Agri-food value chain is an area of significant importance because of providing sustainable, affordable, safety and sufficient food, feed, fibre and fuel to consumers, it is critical to ensure these value chains running smoothly and successfully by applying advanced internet technologies. Blockchain technology is a new digital technological approach underpinned by the Industry 4.0 to ensuring data integrity and preventing tampering and single point failure through offering fault-tolerance, immutability, trust, transparency and full traceability of the stored transaction records to all agri-food value chain partners. This paper used systematic literature network analysis to review the state-of-the-art blockchain technology including its recent advances, main applications in agri-food value chain and challenges from a holistic perspective. The findings suggest that blockchain technology together with advanced information and communication technology and internet of things have been adopted for the improvement of agri-food value chain management in four main aspects: traceability, information security, manufacturing and sustainable water management. Six challenges have been identified including storage capacity and scalability, privacy leakage, high cost and regulation problem, throughput and latency issue, and lack of skills. Based on the critical analysis of literature, research gaps and future research directions are proposed in this paper regarding the applications and challenges of blockchain technology in agri-food value chain management. This study makes contributions to the extant literature in the field of agri-food value chain management by discovering the potential of blockchain technology and its implications for agri-food value chain performance improvements such as food safety, food quality and food traceability.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Over the past several years, organocatalyzed polymerization reactions have attracted considerable attention, and these efforts have led to major advances. A large number of organic compounds have ...been proven active for the polymerization of a large variety of monomers. In particular, phosphazene bases (PBs) are a family of extremely strong, non‐nucleophilic, and uncharged auxiliary bases, and have shown their remarkable potential as organocatalysts for the ring‐opening polymerization (ROP) of cyclic monomers. By deprotonation of weak acids or in combination with lithium cation, PBs significantly enhance the nucleophilicity of the initiator/chain‐end, thus allowing fast and usually controlled anionic polymerization. In this feature article, the recent advances in phosphazene‐catalyzed ROP of cyclic esters are summarized. This review is divided into three sections, including general features, design and synthesis, and catalytic applications. It aims to provide a critical analysis of PB‐mediated ROP systems and a useful guide for the further design of organocatalysts applied to polymer synthesis. An outlook is given at the end.
Phosphazene bases (PBs) are a family of extremely strong and non‐nucleophilic bases having remarkable potential as organocatalysts for different types of polymerization reactions. This feature article emphasizes the general features and synthetic methods of PBs and focuses on their applications in the ring‐opening polymerization of cyclic ester monomers.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Supported gold catalysts play a crucial role in the chemical industry; however, their poor on-stream stability because of the sintering of the gold nanoparticles restricts their practical ...application. The strong metal-support interaction (SMSI), an important concept in heterogeneous catalysis, may be applied to construct the structure of catalysts and, hence, improve their reactivity and stability. Here we report an ultrastable Au nanocatalyst after calcination at 800 °C, in which Au nanoparticles are encapsulated by a permeable TiO
thin layer induced by melamine under oxidative atmosphere. Owning to the formed TiO
overlayer, the resulting Au catalyst is resistant to sintering and exhibits excellent activity and stability for catalytic CO oxidation. Furthermore, this special strategy can be extended to colloidal Au nanoparticles supported on TiO
and commercial gold catalyst denoted as RR2Ti, providing a universal way to engineer and develop highly stable supported Au catalysts with tunable activity.
The United States Cretaceous Western Interior Basin has long been considered a foreland basin, driven by the Sevier thrust and associated basin sediment loads. However, flexural studies demonstrate ...that this effect exists only within a narrow band in front of the thrust belt. Most of the basin appears to be due to mantle flow-induced dynamic subsidence associated with Farallon plate subduction. Here we show how the components of evolving long-wavelength dynamic subsidence and flexural subsidence created the accommodation space and controlled the stratigraphy across the western United States, based on a correlated stratigraphic section across central Utah and Colorado. These backstripped subsidence data reveal the dynamic-topography driven nature of the Western Interior Basin. The results seem to support that the depocenters track the trough of dynamic subsidence with ca. 18 Myr cycles through time and space and the stratigraphic patterns of large-scale progradation, eastward migration of depocenter, and regional clinoform-like downlap are related with the dynamic subsidence. Interpretation of these data also provides more insights into the repeated, ca. 2 to 6 Myr cycles of thrust-induced subsidence in front of the thrust belt, which control the local eastward progradation of the sand bodies from the thrust belt. The dynamic, flexural subsidence and eustatic sea level changes interacted and controlled the timing and distribution of unconformities. Our work shows how the stratigraphy precisely records the timing, patterns and position of dynamic versus flexural subsidences, and that combination of such data leads to important geophysical discoveries and supplies strict constraints for geodynamic modeling.
•Basin depocenters track troughs of dynamic subsidence with ∼18 Myr cycles.•Cycles of thrust-induced subsidence in front of the thrust belt last ∼2 to 6 Myr.•Dynamic, flexure and sea level change interact and control the unconformities.•Western Interior Basin was driven by dynamic versus flexural subsidence.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The present‐day architecture of subducted slabs in the mantle as inferred from seismic tomography is a record of plate tectonics through geological time. The unusually large slab that lies nearly ...horizontally above the 660‐km mantle discontinuity beneath East Asia is presumably from subduction of the Pacific plate. Numerical models have been used to explore the mechanical and geophysical factors that contribute to slab stagnation, but the evolution of this horizontal structure is not fully understood because of uncertainties in the plate‐tectonic history and mantle heterogeneity. Here we show that forward mantle‐flow models constrained by updated tectonic reconstructions can essentially fit major features in the seismic tomography beneath East Asia. Specifically, significant tearing propagated through the subducted western Pacific slab as the Philippine Sea plate rotated clockwise during the Miocene, leading to internal slab segmentation. We believe this tearing associated with Philippine Sea plate rotation also affects the horizontal configuration of slabs.
Plain Language Summary
The present‐day architecture of subducted slabs in the mantle as inferred from seismic tomography is a record of plate tectonics through geological time. The structure of the mantle below East Asia is dominated by a flat slab which extends more than 2,300 km laterally inland (Liu, Zhao, et al., 2017, https://doi.org/10.1016/j.epsl.2017.02.024, https://doi.org/10.1016/j.earscirev.2017.10.012). The origin of this unusual but globally significant flat‐slab structure has been the subject of considerable discussion in the literature through a series of global and high‐resolution seismic inversions. Is this phenomenon caused by unusual regional processes, or have some global mantle processes been overlooked? Here we reproduce this highly unusual flat‐slab structure with a four‐dimensional computational model and argue that this slab is a natural consequence of the plate‐tectonic evolution of East Asia. We provide a solution to this problem through a combination of new plate‐tectonic reconstructions and a 4‐D computational approach that assimilates plate tectonics with the physics of mantle convection. This paper reports a new paradigm for the East Asia margin, where the regional tectonics are characterized by the development of a typical trench‐trench‐trench triple junction, and resultant significant tearing that propagated through the subducted western Pacific slab as the Philippine Sea plate rotated clockwise during the Miocene.
Key Points
A new plate reconstruction of East Asia fully depicts the NE migration of a trench‐trench‐trench triple junction since 30 Ma
This triple‐junction migration led to the overlapping, tearing, and detachment of subducted slabs in East Asia
Large–scale ambient mantle flow should have contributed to the formation of the horizontal slab
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Supramolecular nanomedicines, which use supramolecular design to improve the precision and effectiveness of pharmaceutical practice and optimize pharmacokinetic profiles, have gathered momentum to ...battle cancer and other incurable diseases, for which traditional small‐molecular and macromolecular drugs are less effective. However, the lack of clinical approval of supramolecular assembly‐based medicine underscores the challenges facing this field. A 2D nanodisc‐based supramolecular structure is formed by a non‐ionic heptamethine cyanine (Cy7) dye, which generates fluorescence self‐quenching but unique photothermal and photoacoustic properties. These Cy7‐based supramolecular nanodiscs exhibit passive tumor‐targeting properties to not only visualize the tumor by near‐infrared fluorescence imaging and photoacoustic tomography but also induce photothermal tumor ablation under irradiation. Due to the nature of organic small molecule, they induce undetectable acute toxicity in mice and can be eliminated by the liver without extrahepatic metabolism. These findings suggest that the self‐assembling cyanine discs represent a new paradigm in drug delivery as single‐component supramolecular nanomedicines that are self‐delivering and self‐formulating, and provide a platform technology for synergistic clinical cancer imaging and therapy.
A two‐dimensional nanodisc‐based supramolecular structure is formed by using a nonionic heptamethine cyanine dye. The nanodiscs exhibit unique photothermal and photoacoustic properties to make imaging‐guided tumor therapy a reality. This strategy represents a new paradigm in drug delivery; single‐component supramolecular nanomedicines that are self‐delivering and self‐formulating, providing a technology platform for synergistic clinical cancer imaging and therapy.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
► We introduce variations in basin deposition and formation in North China Craton. ► In Late Triassic, a WNW–ESE orientated intracratonic Ordos basin was developed. ► This basin formation is related ...to paleotethys plate subduction. ► Jurassic walled basin and broken flexural basins indicate the second deformation. ► It is driven by northwestward subduction of the Izanagi plate.
We integrated a systematic sedimentary data into a regional Early Mesozoic stratigraphic framework which demonstrated a detailed picture of spatiotemporal variations in basin deposition and formation in the North China Craton. The Early Mesozoic basin sedimentary evolution is utilized to interpret polyphase tectonism and to unravel the craton deformation. The Late Triassic, nearly WNW-trending, giant intracratonic Ordos basin was widely distributed across most of North China Craton, with a southern wedge-top depozone along the northern East Qilian–Qinling orogenic belt and a northwestern rift depozone along the Helanshan. The continuous subsidence and deposition within the basin were dominantly related to the thrust load of the East Qilian–Qinling belt and inferred mantle flow effects associated with paleotethys plate subduction, and the rift in the northwestern Ordos was driven by nearly north-vergent compression of the eastern North Qilian–North Qinling active margins with the stable North China Craton. This intracratonic Ordos basin formation initiated the deformation of the North China Craton. Formation of the Jurassic NNE-trending walled intracratonic Ordos basin and the broken flexural basins indicates the North China Craton underwent the second, even more abroad nearly NNE trending crustal deformation, with lithosphere thickening in the eastern part of the North China Craton, and dynamic subsidence in the west, which may have been driven by nearly northwestward subduction of the Izanagi plate and the eastward extrusion and underthrusting of the western North China Craton crustal basement.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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