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Seismicity modulation by external stress perturbations in plate boundary *** plate interior

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Geoscience Frontiers 2022年第3期13卷 53-67页

作者： Batakrushna Senapati Bhaskar Kundu Shuanggen Jin Department of earth and Atmospheric sciences NIT RourkelaRourkela 769008India Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China School of Remote Sensing and Geomatics Engineering Nanjing University of Information Science and TechnologyNanjing 210044China

Characterization of critically stressed seismogenic fault systems in diverse tectonic settings can be used to explore the stress/frictional condition of faults,along with its sensitivity for seismicity modulation by periodic stress ***,the process of seismicity modulation in response to external stress perturbation remains *** this paper,the characteristic difference in the seismicity modulation due to resonance destabilization phenomenon governed by rate-and-state friction is presented and val-idated with the globally reported cases of seismicity modulation in diverse tectonic *** rela-tively faster-moving plate boundary regions are equally susceptible for both shorter-period(e.g.,semi-diurnal,diurnal,and other small tidal constituents)and long-period(e.g.,semi-annual,annual,pole tide and pole wobble)seismicity modulation processes in response to stress perturbations from natural har-monic forcing,including tidal,semi-annual,annual,or multi-annual time *** contrast,slowly deforming stable plate interior regions and diffuse deformation zones appear to be more sensitive for long-period seismicity modulation of semi-annual,annual,or even multi-annual time scales but less sen-sitive for short-period seismicity *** finding is also supported by the theoretical model pre-dictions from the resonance destabilization process and worldwide documented natural observations of seismicity modulation in diverse types of tectonic settings.

关键词： Seismicity modulation Resonance destabilization Plate boundary Stable plate interior

Recent geodynamics of major strike-slip zones

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Geodesy and Geodynamics 2015年第5期6卷 361-383页

作者： Trifonov Vladimir G. Korzhenkov Andrey M. Omar Khaled M. Geological Institute Russian Academy of Sciences Institute of Physics of the earth Russian Academy of Sciences

The subject of this study is strike-slip fault zones, where temporal variations of accumulation in strike-slip deformation complicate the standard process of deformation accu- mulation and release during strong earthquakes. These temporal variations are expressed in the E1 Ghab segment of the Dead Sea Transform zone （DST, Eastern Mediterranean） and in the Talas-Fergana fault zone （Central Asia）. According to Global Positioning System （GPS） data, the strike-slip deformations within these zones are not now accumulating or are accumulating at a rate that is significantly less than their average rate during the Holocene and Quaternary or the Pliocene-Quaternary. Simultaneously, weak transverse shortening has been measured in both zones by GPS. In both of these zones, strong earthquakes have not registered within the XX century, yet epochs of intensified seismicity （strong earthquakes） took place throughout history. In the southern and central parts of the E1 Ghab zone, there is evidence of 30 strong historical earthquakes of Ms ≥ 5.7; however, no instrumental earthquakes of Ms 〉 5 have been identified. The temporal distribution of seismic energy released by these earthquakes demonstrates a 350 ± 50-year cycle. Values for the seismic energies released during the peak phases of these cycles are approximated by a sinusoid that suggests the possibility of a 〉1800-year cycle （＂hyper-cycle＂）, which began around the 3rd century, reached its maximum in the 12th century, and has continued until now. A combination of geological, archaeoseismological, and geodetic data show that the rate of sinistral strike-slip deformation varied in the fault zone, probably in conformity with the variation of seismicity during the ＂hyper-cycle.＂ In the Talas-Fergana fault zone, trenching and 14C dating that was correlated with right lateral offsets, gave a possible preliminary estimate of the average rates of the Late Holocene strike slip of about 10 mm per year, with a decrease in the SE directi

关键词： Active strike-slip faultsHistorical seismicity Paleoseismicity Temporal variations of focalmechanisms of earthquakes Rates of accumulation of strike-slipdeformation

Impacts of climate gradients on the vegetation phenology of major land use types in Central Asia （1981-2008）

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Frontiers of earth Science 2012年第2期6卷 206-225页

作者： Jahan KARIYEVA Willem J.D. van LEEUWEN Connie A. WOODHOUSE School of Geography and Development The University of Arizona Tucson AZ 85721 USA School of Natural Resources and the Environment - Office of Arid Lands Studies - Arizona Remote Sensing Center The University of Arizona Tucson AZ 85721 USA

Time-series of land surface phenology （LSP） data offer insights about vegetation growth patterns. They can be generated by exploiting the temporal and spectral reflectance properties of land surface components. Inter- annual and seasonal LSP data are important for under- standing and predicting an ecosystem＇s response to variations caused by natural and anthropogenic drivers. This research examines spatio-temporal change patterns and interactions between terrestrial phenology and 28 years of climate dynamics in Central Asia. Long-term （1981-2008） LSP records such as timing of the start, peak and length of the growing season and vegetation productivity were derived from remotely sensed vegetation greenness data. The patterns were analyzed to identify and characterize the impact of climate drivers at regional scales. We explored the relationships between phenologi- cal and precipitation and temperature variables for three generalized land use types that were exposed to decade- long regional drought events and intensified land and water resource use： rainfed agriculture, irrigated agriculture, and non-agriculture. To determine whether and how LSP dynamics are associated with climate patterns, a series of simple linear regression analyses between these two variables was executed. The three land use classes showed unique phenological responses to climate variation across Central Asia. Most of the phenological response variables were shown to be positively correlated to precipitation and negatively correlated to temperature. The most substantial climate variable affecting phenological responses of all three land use classes was a spring temperature regime. These results indicate that future higher temperatures would cause earlier and longer growing seasons.

关键词： phenology land use climate variability

The Shishugou Fauna of the Middle-Late Jurassic Transition Period in the Junggar Basin of Western China

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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1115-1135页

作者： XU Xing James M.CLARK David A.EBERTH Philip J.CURRIE Centre for Vertebrate Evolutionary Biology Yunnan UniversityKunming 650500China Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China Department of Biological sciences George Washington UniversityWashington DC20052USA Royal Tyrrell Museum of Palaeontology Box 7500DrumhellerAlberta T0J 0Y0Canada Department of Biological sciences University of Alberta 116 Street and 85 AvenueEdmontonAB T6G 2R3Canada

The Middle-Late Jurassic transition period is a critical period for the evolution of terrestrial vertebrates,but the global fossil record from this time is relatively *** Shishugou Fauna of this period has recently produced significant fossil remains of dinosaurs and other vertebrate groups,some representing the earliest known members of several dinosaurian groups and other vertebrate groups and some representing the best-known specimens of their *** discoveries are significant for our understanding of the origin and evolution of several vertebrate *** dating indicates that the fauna is aged approximately 159-164 *** with other similarly-aged terrestrial faunas such as Shaximiao and Yanliao show both taxonomic similarities and differences between these faunas and indicate that the Junggar deposits might have preserved the most complete vertebrate fossil record for a Middle-Late Jurassic Laurasian terrestrial fauna.

关键词： Middle-Late Jurassic Shishugou Fauna Shishugou Formation terrestrial ecosystem Shaximiao Yanliao Junggar Basin

Studies of mineral properties at mantle condition using Deformation multi-anvil apparatus

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Progress in Natural Science:Materials International 2009年第11期19卷 1467-1475页

作者： Li Li MPI,Department of Geosciences,Stony Brook University,Stony Brook,NY 11794,USA MPI Department of Geosciences Stony Brook University Stony Brook NY 11794 USA

This paper reports recent studies of the rheological and viscoelastic properties of minerals at mantle pressure and temperature using Deformation multi-anvil apparatus(D-DIA).Stress-strain-time relations were measured using synchrotron X-ray radiation to determine these *** properties of San Carlos olivine were measured at pressure up to 10 GPa and indicated that the effect of pressure on the viscosity of olivine is much smaller than previous *** unique capability of synchrotron X-ray can resolve the stress heterogeneity within a polycrystalline material as well as within a multi-phase mixture and elucidate the stress-strain distribution in an *** measurements were carried out using olivine as the sample at mantle pressure and *** results showed that grain boundary activity rather than pressure dominate the relaxation *** aim of this paper is to illustrate the methods using new tools for high pressure research.

关键词： High pressure Synchrotron X-ray Multi-anvil Plasticity Anelasticity

Crystallization and impact history of a meteoritic sample of early lunar crust(NWA 3163)refined by atom probe geochronology

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Geoscience Frontiers 2019年第5期10卷 1841-1848页

作者： L.F. White D.E. Moser K.T. Tait B. Langelier I. Barker J.R. Darling Centre for Applied Planetary Mineralogy Department of Natural HistoryRoyal Ontario MuseumTorontoOntarioM5S 2C6Canada Department of earth sciences University of TorontoTorontoOntarioM5S 3B1Canada Department of earth sciences University of Western OntarioLondonN6A 5B7Canada Canadian Centre for Electron Microscopy McMaster UniversityHamiltonOntarioCanada School of earth and Environmental Science University of PortsmouthPortsmouthUK

Granulitic lunar meteorites offer rare insights into the timing and nature of igneous,metamorphic and impact processes in the lunar *** dating the different events recorded by these materials is very challenging,however,due to low trace element abundances (***,Nd,Lu,Hf),rare micrometerscale U-Th-bearing accessory minerals,and disturbed Ar-Ar systematics following a multi-stage history of shock and thermal *** we report on micro-baddeleyite grains in granulitic mafic breccia NWA 3163 for the first time and show that targeted microstructural analysis (electron backscatter diffraction) and nanoscale geochronology (atom probe tomography) can overcome these barriers to lunar chronology.A twinned (-90°/) baddeleyite domain yields a 232Th/208Pb age of 4328 ± 309 Ma,which overlaps with a robust secondary ion mass spectrometry (SIMS) 207Pb/206Pb age of 4308± 18.6 Ma and is interpreted here as the crystallization age for the igneous protolith of NWA 3163.A second microstructural domain,< 2 mm in width,contains patchy overprinting baddeleyite and yields a Th-Pb age of 2175± 143 Ma,interpreted as dating the last substantial impact event to affect the *** finding demonstrates the potential of combining microstructural characterization with nanoscale geochronology when resolving complex P-T-t histories in planetary materials,here yielding the oldest measured crystallization age for components of lunar granulite NWA 3163 and placing further constraints on the formation and evolution of lunar crust.

关键词： Baddeleyite U-Th-Pb isotopes EBSD Atom probe tomography Geochronology Northwest Africa 3163

Evidence of proteins, chromosomes and chemical markers of DNA in exceptionally preserved dinosaur cartilage

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National Science Review 2020年第4期7卷 815-822页

作者： Alida M.Bailleul Wenxia Zheng John R.Horner Brian K.Hall Casey M.Holliday Mary H.Schweitzer Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences CAS Center for Excellence in Life and Paleoenvironment Department of Biological sciences North Carolina State University Department of Geology University of Lund Honors Program Chapman University Department of Pathology and Anatomical sciences University of Missouri North Carolina Museum of Natural sciences Department of Biology Dalhousie University

A histological ground-section from a duck-billed dinosaur nestling(Hypacrosaurus stebingeri) revealed microstructures morphologically consistent with nuclei and chromosomes in cells within calcified *** hypothesized that this exceptional cellular preservation extended to the molecular level and had molecular features in common with extant avian cartilage. Histochemical and immunological evidence supports in situ preservation of extracellular matrix components found in extant cartilage, including glycosaminoglycans and collagen type II. Furthermore, isolated Hypacrosaurus chondrocytes react positively with two DNA intercalating stains. Specific DNA staining is only observed inside the isolated cells, suggesting endogenous nuclear material survived fossilization. Our data support the hypothesis that calcified cartilage is preserved at the molecular level in this Mesozoic material, and suggest that remnants of once-living chondrocytes, including their DNA, may preserve for millions of years.

关键词： cartilage dinosaur nuclei chromosomes collagen Ⅱ DNA markers

Hardening Effects in Superhard Transition-Metal Borides

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Accounts of Materials Research 2022年第1期3卷 100-109页

作者： Lisa E.Pangilinan Shanlin Hu Spencer G.Hamilton Sarah H.Tolbert Richard B.Kaner Department of Chemistry and Biochemistry University of CaliforniaLos Angeles(UCLA)Los AngelesCalifornia 90095United States Department of Chemistry and Biochemistry Department of Materials Science and Engineeringand California NanoSystems Institute(CNSI)University of CaliforniaLos Angeles(UCLA)Los AngelesCalifornia 90095United States

CONSPECTUS:Mechanical hardness is a physical property used to gauge the applications of materials in the manufacturing and machining *** of their high hardness and wear resistance,superhard materials(Vickers hardness,Hv≥40 GPa)are commonly used as cutting tools and *** diamond is the hardest known material used for industrial applications,its synthesis requires both high pressure and high *** in the field of superhard materials research has led to the search for alternatives with high hardness and thermal stability at low *** discovery of novel ultraincompressible,superhard materials has largely developed through trial and error along two *** one approach,researchers combine light elements,such as boron,carbon,nitrogen,and oxygen,often at high pressure,to replicate the highly directional,dense,covalent bonds of *** the second approach,these light elements(B,C,N,and O)are combined with highly incompressible,electron-rich transition metals to form dense covalently bonded networks at ambient pressure.

关键词： Transition boron gauge

Rapid growth of environmental research in China

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Journal of Environmental sciences 2016年第1期28卷 1-3页

作者： Guibin Jiang Chunxia Wang X.Chris Le State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China division of Environmental Chemistry Department of Chemical Sciences National Natural Science Foundation of China Beijing 100085 China division of Analytical and Environmental Toxicology Department of Laboratory Medicine and Pathology Faculty of Medicine and Dentistry University of Alberta Edmonton AB T6G 2G3 Canada

Environmental research in China has grown tremendously over the last thirty *** rapid and sustained growth has been supported by the remarkable increases in research funding,the number of graduate students,the degree-offering programs in environmental sciences and engineering,the state-of-the-art facilities,and international collaboration.

关键词： Rapid growth of environmental research in China