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Dating Fault Activity Based on Surface Texture of Quartz Grains from the Bailong River Fault

Acta Geologica Sinica(English Edition) 2014年第4期88卷 1131-1144页

作者： SHEN Junfeng YANG Weimin LIU Ting HUANG Xiao ZHENG Weijie YU Lei WANG Guoqiang School of Earth science and Resources China University of Geosciences institute of Geomechanics Chinese Academy of Geological Sciences

Much important information referring to fault motion （e.g., fault activities period, intensity, frequency, and even dynamic background） can be revealed by resolving fault gouge, which is the result of fault motion while extruding or grinding. The field investigation encompassed sample collecting from the Bailong River fault system of the western segment of the Qinling Orogenic Belt （QOB）; 44 samples of fault gouges were collected for quartz micro-morphology analysis. These samples were analyzed using field emission scanning electron microscopy. In addition, 14 samples were tested for thermo-luminescence dating. The results showed that most of the surface textures of quartz grains are characterized by fish scale, moss-like texture, and stalactite. However, a small amount of orange peel-like fractures and worm-hole-like shaped surface texture were observed. Moreover, a few typical conchoids or subconchoidal fractures in quartz grains can be seen. This implies that the Bailong River Fault was active repeatedly during the Quaternary period, but the main motion period is the Pleistocene. The 14 thermo-luminescence dating values showed two age groups： 343.29-184.06 ka and 92.18-13.87 ka. These study data reveal that fault movement started during the Pliocene, occurred frequently in the early-middle period of the Pleistocene, and the peak frequency of the motion was reached in the early Pleistocene. The fault motions were stopped terminated in the early Holocene. The results are significant for the natural disaster risk evaluation in the western segment of the QOB.

关键词： fault gouge surface texture of quartz thermo-luminescence dating Pleistocene BailongRiver Fault

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Optimization of thermoacoustic refrigerator using response surface methodology

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Journal of Hydrodynamics 2013年第1期25卷 72-82页

作者： HARIHARAN N. M. SIVASHANMUGAM P. KASTHURIRENGAN S. Department of Chemical Engineering National Institute of Technology centre for Cryogenic Technology Indian Institute of Science

Thermoacoustic refrigerator （TAR） converts acoustic waves into heat without any moving parts. The study presented here aims to optimize the parameters like frequency, stack position, stack length, and plate spacing involving in designing TAR using the Response Surface Methodology （RSM）. A mathematical model is developed using the RSM based on the results obtained from DeltaEC software. For desired temperature difference of 40 K, optimized parameters suggested by the RSM are the frequency 254 Hz, stack position 0.108 m, stack length 0.08 m, and plate spacing 0.0005 m. The experiments were conducted with optimized parameters and simulations were performed using the Design Environment for Low-amplitude ThermoAcoustic Energy Conversion （DeltaEC） which showed similar results.

关键词： Design Environment for Low-amplitude ThermoAcoustic Energy Conversion (DeltaEC) optimization Response Surface Methodology (RSM) temperature difference thermoacoustic refrigerator (TAR)

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The Yanshan orogeny and late Mesozoic multi-plate convergence in East Asia—Commemorating 90th years of the “Yanshan Orogeny”

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science China Earth sciences 2018年第12期61卷 1888-1909页

作者： Shuwen DONG Yueqiao ZHANG Hailong LI Wei SHI Huaimin XUE Jianhua LI Shiqi HUANG Yongchao WANG School of Earth sciences and Engineering Nanjing University Sinoprobe Center Chinese Academy of Geological Sciences institute of Geomechanics Chinese Academy of Geological Sciences institute of Geology Chinese Academy of Geological Sciences

The Yanshan movement/orogeny has been proposed for 90 years, which is of special significance in the history of geological research in China. This study conducted a review by synthesizing major achievements regarding episodic deformation features, sedimentary and magmatic records of the Yanshan orogeny in China, and clarified the episodic tectono-magmatism and its geodynamic origins. The tectonic implications of the Yanshan orogeny are discussed in the context of global plate tectonics and supercontinent reconstruction. Lines of evidence from structural, sedimentary and magmatic data suggest that the Yanshan orogeny represents a regional-scale tectonic event that affected the entire China continent in late Mesozoic period. Numerous age and structural constraints consistently indicate that the Yanshan orogeny was initiated in the Jurassic(at ～170±5 Ma). and was characterized by alternating stages of crustal shortening at ～170–136 Ma, crustal extension at ～135–90 Ma, and weak shortening at ～80 Ma. The 170–136 Ma crustal shortening was reflected in the generation of two regional stratigraphic unconformities(the Tiaojishan and Zhangjiakou unconformities), which were initially named the A and B episodes of "the Yanshan Orogeny" by *** Wenhao in 1928. Geodynamically, the Yanshan orogeny in East Asia was associated with nearly coeval oceanic subduction and continental convergence in the Paleo-Pacific, Neo-Tethys, and Mongol-Okhotsk tectonic domains. As a consequence, three giant accretionary-collisional tectonic systems were formed along the continental margins of East Asia, i.e., the Mongol-Okhotsk, Bangonghu-Nujiang, and SE China subduction-and collision-related accretionary systems. The Yanshan orogeny induced widespread crustal-scale folding and thrusting, tectonic reactivation of long-lived zones of crustal weakness,and extensive magmatism and mineralization in intraplate regions. Based on the time principle of supercontinent assembly and break-up, we propose that

关键词： Yanshan orogeny Mid-Late Jurassic East Asia plate convergence Intracontinental orogeny Amasia supercontinent

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Influence of Sputtering Pressure on the Structure and Mechanical Properties of Nanocomposite Ti-Si-N Thin Films

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Journal of Materials science & Technology 2010年第8期26卷 673-678页

作者： Vipin Chawla R.Jayaganthan Ramesh Chandra Department of Metallurgical and Materials Engineering & centre of Nanotechnology Indian Institute of Technology Roorkee Nano science Laboratory Institute Instrumentation CentreIndian Institute of Technology Roorkee

Nanocomposite Ti-Si-N thin films have been deposited on Si （100） substrate by direct current/radio frequency （DC/RF） magnetron sputtering. The effect of varying deposition parameters on the structure and mechanical properties of Ti-Si-N films has been investigated by characterization techniques such as X-ray dif- fraction （XRD）, field emission scanning electron microscopy （FE-SEM）, atomic force microscopy （AFM） and nanoindentation, respectively. XRD analysis of the thin films exhibit all （111）, （200） and （220） peaks initially with varying sputtering pressure, but （111） peak dominates at higher sputtering pressure. The crystallite size calculated from XRD peaks shows that it increases with increasing sputtering pressure. Microstructural analy- sis reveals that the dense blurred grains transform into uniform grains in the films and shows porosity with increasing sputtering pressure. The surface roughness of the Ti-Si-N films increases with varying sputtering pressure. The hardness and Youngrs modulus values of Ti-Si-N films are 33.7 and 278.6 GPa, respectively, with 0.7 Pa sputtering pressure but it decreases with further increase in sputtering pressure due to an increase in porosity of the films.

关键词： Ti-Si-N films Nanoindentation Microstructural characterization

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New Discovery of Reproductive Organs and Spores in Situ of Ginkgoales and Czekanowskiales from the Middle Jurassic of Shaanxi, China

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2314-2315页

作者： GUO Caiqing YAO Jianxin Key Laboratory of Stratigraphy and Paleontology Institute of GeologyChinese Academy of Geological Science

Objective Ginkgoales and Czekanowskiales are important components of Mesozoic flora and were widely distributed in the Northern Hemisphere. They are usually preserved together in the stratum. Their fossils are abundant in the Middle Jurassic of Shaanxi Province, but there are no reports on their reproductive organs. Here, we report two male gymnospermous pollen cones from the Middle Jttrassic Yan＇an Formation of the northeast Yulin City, Shaanxi Province, China. The characteristics of the fossils, including those of pollens, have been described in detail. The new specimens were compared with fossils closely similar in morphology, and the taxonomic affinity and systematies were established. The present results offer new fossil materials for the study of taxonomy, evolution, and phytogeography of Ginkgoales and Czekanowskiales.

关键词： New Discovery of Reproductive Organs and Spores Situ of Ginkgoales Czekanowskiales from the Middle Jurassic of Shaanxi

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Geochemical Constraints of Sediments on the Provenance, Depositional Environment and Tectonic Setting of the Songliao Prototype Basin

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Acta Geologica Sinica(English Edition) 2002年第4期76卷 455-462页

作者：阎全人高山林王宗起李继亮肖文交侯泉林阎臻陈海泓 institute of Geology & Geophysics Chinese Academy of Science Beijing 100029 Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 institute of Geology & Geophysics Chinese Academy of Science Beijing 100029 institute of Geology Chinese Academy of Geological Sciences Beijing 100037

The geochemistry of sediments is primarily controlled by their provenances,and different tectonic settings have distinctive provenance characteristics and sedimentaryprocesses. So, it is possible to distinctive provenances, depositional environments and tectonicsettings in the development of a sedimentary basin with the geochemistry of the clastic rocks. Theanalytical results of the present paper demonstrate that sediments in the Songliao prototype basinare enriched in silica (SiO_2=66.48-80.51 percent), and their sumREE are 30-130 times of that ofchondrite with remarkable Eu anomalies. In discriminating diagrams of Eu/Eu* vs sumREE and (La/Yb)_Nvs sumREE, most samples locate above the line Eu/Eu*=1, on the right of the line Eu/Eu*/sumREE=1and under the line La/Yb)_N/sumREE=1/8, which indicates that the depositional environment ofsediments in the basin was oxidizing. In addition, variations of MgO, TiO_2, Al_2O_3, FeO + Fe_2O_3,Na_2O and CaO vs SiO_2 reflect a tendency of increasing mineral maturity of sediments in the *** also show that the protolytes of the sediments in the basin were felsic igneous rocks, andthe Songliao prototype basin was in a tectonic setting of an island arc on an active continentalmargin, with violent sinistral strike-slip.

关键词： Songliao prototype basin geochemistry of sediment provenance depositionalenvironment tectonic setting

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Archean of Greenland and Fennoscandia

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Episodes 2008年第1期31卷 13-19页

作者： Pentti Hoelttae Victor Balagansky Adam A. Garde Satu Mertanen Petri Peltonen Alexander Slabunov Peter Sorjonen-Ward Martin Whitehouse geological Survey of Finland P.O. Box 96 FI-02151 Espoo Finland. geological institute Kola Science Centre RAS Apatity 184209 Russia. geological Survey of Denmark and Greenland Фster Voldgade 10 DK-1350 Copenhagen K Denmark. institute of Geology Karelian Research Centre RAS Petrozavodsk 185910 Russia. geological Survey of Finland P.O. Box 1237 FI-70211 Kuopio Finland. Laboratory for Isotope Geology Swedish Museum of Natural History Box 50 007 SE-104 05 Stockholm Sweden.

The North Atlantic craton in southern West Greenland mainly consists of a tectonic collage of Mesoarchean continental crustal terranes, which were amalgamated at c. 2.7 Ga and are currently exposed at mid-crustal amphibolite to granulite facies levels. Tonalitic orthogneisses predominate, intercalated with slightly older tholeiitic to andesitic metavolcanic rocks and associated gabbro-anorthosite intrusive complexes. The North Atlantic craton also contains enclaves of Eoarchean, c. 3.86-3.6 Ga orthogneisses and supracrustal rocks including the Isua greenstone （or supracrustal） belt. This is the oldest known assemblage of rocks deposited at the surface of the Earth, comprising mafic pillow lavas, banded iron formations and metasedimentary schists with local disseminated graphite of possible biogenic origin. Eoarchean rocks have not been found in kola and Karelia in Fennoscandia where most rocks are 2.9-2.7 Ga tonalitic-trondhjemitic-granodioritic orthogneisses with intercalated coeval greenstone belts and amphibolites. Mesoarchean 3.0-3.2 Ga rocks are found in the eastern and western parts of the Karelian province. Subduction-related rocks like the Iringora supra-subduction type ophiolite and basalt-andesite-dacite-rhyolite series volcanic rocks in many greenstone belts, as well as eclogites are found in the Archean of Fennoscandia. A clear distinction between Greenland and Fennoscandia is the abundance of 2.75-2.65 Ga igneous rocks in Fennoscandia which indicates that these two cratons had a separate evolution during the Neoarchean.

关键词：太古代地球科学格陵兰岛芬诺斯坎底亚

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Limited acid deposition inferred from diatoms during the 20th century--A case study from lakes in the Tatra Mountains

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Journal of Environmental sciences 2018年第2期30卷 92-106页

作者： Elwira Sienkiewicz Michal Gasiorowski institute of geological sciences Polish Academy of Sciences Research Centre at Warsaw St. Twarda SI/SS Warsaw PL-00818 Poland

Mountain lakes are usually sensitive to the effects of global and regional environmental changes. Since the second half of the 20 th century, surface-water acidification has become a significant ecological problem, and many lakes in Europe and North America have anthropogenically acidified. Additionally, following reduction in emissions of sulfur（S） and nitrogen（N） compounds, recovery from acidification has been observed in many lakes. In this study, we used changes in diatom communities to reconstruct the p H histories based on changes recorded in nine Tatra lakes（Western Carpathians, Poland） since approximately1850 AD. Overall, results indicate that acidic precipitation had little influence on lake-water p H in the Tatra Mountain lakes. Changes in diatom-inferred p H（DI-p H） generally were small and showed little evidence of acidification during the time of the highest air pollution（since the 1960 s）, and have shown little change since the reduction of acidic deposition since the 1990 s. Lakes that showed some evidence of acidification included dystrophic lakes with low acid neutralizing capacity. However, as illustrated by the PCA trajectories of the diatom assemblages, the majority of the lakes currently contain diatom assemblages that are unlike the diatom floras that existed ca. 1850.

关键词： Lake Palaeolimnology Environmental impact assessment Algae Acidification Pollution

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Sedimentary and environmental history of the Late Permian Bonikowo Reef(Zechstein Limestone, Wuchiapingian), western Poland

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Journal of Palaeogeography 2017年第3期6卷 183-205页

作者： Pawe? Raczyński Tadeusz Marek Peryt Wac?aw Strobel institute of geological sciences University of Wroc?aw Polish geological instituted-National Research institute institute of Agrophysics Polish Academy of Sciences

The Bonikowo Reef occurs in the central part of the Zechstein Limestone Basin in western Poland and was growing on the topmost edges of tilted blocks and/or on the top of uplifted horsts of the BrandenburgeWolsztynePogorzela High. Its size is ca. 1.6 km^2. The Bonikowo Reef shows the thickest reef section（90.5 m） recorded in the High. The Zechstein Limestone unit is represented mostly by limestones, often thoroughly recrystallized, although the macrotextures and biota of the boundstone are identifiable in most cases. The drillcore section is a mixture of boundstones（microbial and bryozoan）, wackestones, packstones and grainstones, which often co-occur. The δ^13 C and δ^18 O values for both calcite（avg. 3.8 ± 0.8‰ and-3.4 ± 1.7‰, respectively） and dolomite（avg. 3.5 ± 0.7‰ and-5.2 ± 1.3‰, respectively） are transitional between the values previously reported for condensed sequences of the basinal facies and larger reef complexes. The biofacies of the Bonikowo Reef are very similar to those recognized in other reefs of the BrandenburgeWolsztynePogorzela High, which owe their origin to the destruction of bryozoan boundstones. The biota composition is typical and characteristic of other Zechstein Limestone reefs. However, the Bonikowo Reef demonstrates the importance of microbialites, laminar and nodose encrustations, in the growth and cohesion of the Zechstein Limestone reefs. Such encrustations abound within the Zechstein Limestone although, in many cases, the real nature of the encrustations is difficult to ascertain. These laminated encrustations show great similarity to Archaeolithoporella that is one of the most important Permian reefbuilding organisms. The encrustations considered to represent Archaeolithoporella were also previously recorded in the Zechstein Limestone of western Poland and in its stratigraphic equivalent, the Middle Magnesian Limestone of Northeast England. The lower part of the sequence shows great biofacies variability that reflects common envir

关键词： Bonikowo Reef Zechstein Limestone Wuchiapingian Biofacies Carbon and oxygen isotopes

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Cenozoic Evolution of Sediments and Climate Change and Response to Tectonic Uplift of the Northeastern Tibetan Plateau

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Acta Geologica Sinica(English Edition) 2014年第3期88卷 949-962页

作者： LIANG Xia JI Junliang LU Jingfang KE Xue AI Keke XU Yadong SONG Bowen institute of Geomechanics Chinese Academy of Geological Sciences Key Laboratory of Biogeology and Environmental Geology China University of Geosciences School of Earth science China University of Geosciences institute of Oceanology China Geological Survey School of Geophysics and Geomatics China University of Geosciences institute of geological Survey China University of Geosciences

Through a comprehensive study of magnetostratigraphy and sedimentology of several basins in the northeastern Tibetan Plateau,we reveal that the study area mainly experienced six tectonic uplift stages at approximately 52 Ma,34-30 Ma,24-20 Ma,16-12 Ma,8-6 Ma,and 3.6-2.6 *** analyses of pollen assemblages from the Qaidam,Linxia,Xining,and West Jiuquan Basins show that the northeastern Tibetan Plateau has undergone six major changes in vegetation types and climate：50-40 Ma for the warm-humid forest vegetation,40-23 Ma for the warm-arid and temperate-arid forest steppe vegetation,23-18.6 Ma for the warm-humid and temperate-humid forest vegetation,18.6-8.5 Ma for the warm-humid and cool-humid forest steppe vegetation,8.6-5 Ma for the temperate sub-humid savanna steppe vegetation,and 5-1.8 Ma for the cold-arid steppe *** comparisons of tectonic uplift events inferred from sedimentary records,climatic changes inferred from pollen,and global climate changes show that in the northeastern Tibetan Plateau the climate in the Paleogene at low altitude was mainly controlled by the global climate change,while that in the Neogene interval with high altitude landscapes of mountains and basins is more controlled by altitude and morphology.

关键词： Magnetostratigraphy tectonic uplift sedimentation rates paleoclimate Tibetan Plateau

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