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底辟构造启动及其沉积建造形成机制探讨——来自物理模拟的启示
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作者 何文刚 沈传波 +2 位作者 吴磊 李生红 赵远雯 《大地构造与成矿学》 EI CAS CSCD 北大核心 2023年第5期1069-1084,共16页
底辟构造因与造山带和盆地的变形演化过程以及油气资源分布关系密切而备受关注,到目前为止,有关底辟构造的形成环境、变形样式以及成因机制研究,已取得了许多重要的成果和认识,但对于盐岩或者泥岩底辟的启动及其沉积建造形成机制的模拟... 底辟构造因与造山带和盆地的变形演化过程以及油气资源分布关系密切而备受关注,到目前为止,有关底辟构造的形成环境、变形样式以及成因机制研究,已取得了许多重要的成果和认识,但对于盐岩或者泥岩底辟的启动及其沉积建造形成机制的模拟探讨仍然十分不足。本研究利用物理模拟技术,建立差异的初始地貌、塑性层之上覆盖层厚度、沉积速率以及基底与侧向摩擦力差异4组基底硅胶与其上覆石英砂组合模型,对底辟的初始启动条件及其沉积建造的形成机制进行了模拟分析和探讨。结果表明,地貌差异是盐丘或泥丘构造产生的初始必要条件,即在伸展、挤压环境以及由构造作用所形成的薄弱带等均有利于底辟构造的快速启动;而在底辟沉积建造过程中,快速的沉积加载、塑性层之上沉积层的初始厚度越大,以及具有较大的侧向与基底摩擦力,则会抑制早期底辟的发育;而缓慢的沉积作用、塑性层之上初始沉积层厚度越薄以及减小侧向与基底摩擦力,则会促进早期底辟的生长。同时在底辟沉积建造的中后期,随着沉积速率的加载,底辟会快速的生长变形。综合模拟结果和实际的底辟沉积建造过程表明,底辟沉积建造是地貌、沉积速率、地层温度、地层压力和底辟塑性流体埋深等综合作用的结果,正如北海盆地盐底辟和安达曼海弧后盆地泥底辟的沉积建造过程,在形成机制上与模拟结果具有较大的相似性。 展开更多
关键词 底辟沉积建造 初始地貌沉积速率 覆盖层厚度控制 基底与侧向摩擦力 物理模拟
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运动速度对褶皱—冲断带的构造变形样式的影响分析——来自硅胶和石英砂组合模型的模拟启示
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作者 何文刚 李生红 +2 位作者 刘重庆 赵远雯 骆忧 《地质论评》 CAS CSCD 北大核心 2023年第2期469-480,共12页
运动速度与构造样式之间或许存在一定的内在联系,充分认识它们之间的关系对理解自然界的构造变形演化过程具有十分重要意义。为此,笔者等结合野外露头观察,开展了脆—韧性结构条件下,不同的变形速率对褶皱—冲断带的构造样式影响的物理... 运动速度与构造样式之间或许存在一定的内在联系,充分认识它们之间的关系对理解自然界的构造变形演化过程具有十分重要意义。为此,笔者等结合野外露头观察,开展了脆—韧性结构条件下,不同的变形速率对褶皱—冲断带的构造样式影响的物理模拟测试分析。结果表明:(1)高应形速率形成以前冲为主的构造样式,中等应形速率形成以前冲和后冲为主的构造样式,而低应形速率则形成以纯后冲为主的构造样式。(2)构造变形样式的差异主要是物质内部的应力状态所决定的:褶皱—冲断带的根带,脆性层剪应力大于基底韧性层的剪应力,形成以前冲断裂为主的构造样式;而褶皱—冲断带的中段和前缘地区,脆性层的剪应力和基底韧性层的剪应力较为接近,形成后冲和对称性冲起构造为主。(3)构造地质体的变形速率很可能决定了其存在的物质状态。葡萄牙南部滨岸带的布丁构造和北美卡斯卡底古陆的纯后冲构造等特殊的构造样式极有可能是在差异的变形速率下形成。 展开更多
关键词 变形速率 构造样式 演化过程 褶皱—冲断带 物理模拟
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High-precision geochronology of Mesozoic magmatism in Macao,Southeast China:Evidence for multistage granite emplacement 被引量:2
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作者 Pedro Quelhas Agata Alveirinho Dias +2 位作者 Joao Mata Donald Wayne Davis Maria Luísa Ribeiro 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第1期243-263,共21页
Six new high precision U-Pb zircon ID-TIMS ages plus thirteen in situ high spatial resolution U-Pb zircon LA-MC-ICPMS ages are reported from Jurassic plutonic(metaluminous to weakly peraluminous biotite granites)and J... Six new high precision U-Pb zircon ID-TIMS ages plus thirteen in situ high spatial resolution U-Pb zircon LA-MC-ICPMS ages are reported from Jurassic plutonic(metaluminous to weakly peraluminous biotite granites)and Jurassic to Cretaceous hypabyssal(dacites)rocks from Macao.Despite its relatively small area(~30 km^2),the new ages tightly constrain the Macao granitic magmatism to two periods ranging from 164.5±0.6 Ma to 162.9±0.7 Ma and 156.6±0.2 Ma to 155.5±0.8 Ma,separated by ca.6 Ma.Inherited zircons point to the existence of a basement with ages up to Paleo-Proterozoic and late Archean in the region.In addition,younger dacitic rocks were dated at 150.6±0.6 Ma and<120 Ma.U-Pb zircon ages and whole-rock REE data of Macao granites indicate that the first pulse is also represented in Hong Kong and Southeast(SE)China,while magmatism with the chemical characteristics of the second pulse seems to not be represented outside Macao.The two granitic magmatic pulses have distinct mineralogical and geochemical features that support their discrete nature rather than a continuum of comagmatic activity and suggest that the Macao granitic suite was incrementally assembled during a period of ca.9 Ma,a hypothesis also extendable to the neighboring Hong Kong region for a time lapse of ca.24 Ma.In Macao,the transition from granitic magmatism(Middle to Upper Jurassic)to the younger dacite dykes(Upper Jurassic to Lower Cretaceous)most likely corresponds to a change in the regional tectonic setting,from an extensional regime related with foundering of the subducting paleoPacific plate during the Early Yanshanian period to the reestablishment of a normal subduction system in SE China during the Late Yanshanian period. 展开更多
关键词 GRANITES U-Pb geochronology Zircon JURASSIC Yanshanian orogeny MACAO
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Refining the Stratigraphy of the Taghdout Group by Using the U-Pb Geochronology of the Taghdout Sill(Zenaga inlier,Anti-Atlas,Morocco)
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作者 Abdelhak AIT LAHNA Colombo Celso Gaeta TASSINARI +9 位作者 Nasrrddine YOUBI Hassan ADMOU Joao MATA El Hafid BOUOUGRI Latifa CHAIB Richard E.ERNST Ulf SODERLUND Moulay Ahmed BOUMEHDI Mohamed Khalil BENSALAH El Mostapha AARAB 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期1-,共1页
The Anti-Atlas belt of southern Morocco is situated on the northern edge of the West African craton(WAC).It corresponds to a broad anticlinorium some 800 km long and 200 km wide,trending ENE-WSW,parallel to the
关键词 Pb Zenaga inlier Morocco Refining the Stratigraphy of the Taghdout Group by Using the U-Pb Geochronology of the Taghdout Sill ANTI-ATLAS
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New Dinosaur Tracks from the Lower Barremian of Portugal (Areia do Mastro Formation, Cape Espichel)
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作者 Silvério D. Figueiredo Carlos Neto de Carvalho +1 位作者 Pedro P. Cunha Ismar de Sousa Carvalho 《Journal of Geoscience and Environment Protection》 2021年第1期84-96,共13页
We present a new tracksite with multiple dinosaur tracks from the lowermost Barremian (Lower Cretaceous) of the Cape Espichel (Sesimbra, Portugal). The tracks are localized on three beds on the top carbonate beds of t... We present a new tracksite with multiple dinosaur tracks from the lowermost Barremian (Lower Cretaceous) of the Cape Espichel (Sesimbra, Portugal). The tracks are localized on three beds on the top carbonate beds of the Areia do Mastro Formation. Those bioclastic, nodular limestones were deposited in a very shallow subtidal-intertidal, restricted lagoon environment. The track surfaces are very dinoturbated, with a substantial number of tracks. Several tracks assign to sauropods, ornithopods and theropods dinosaurs were recorded. Due to heavy bioturbation and the preservation conditions, it is not possible to define trackways;some preliminary work done on the tracks could disclose some behaviours of their producers. Several species of carnivore and herbivore dinosaurs crossed that large area at different times. Herbivores may have used the lagoon margin as passage between feeding spots, while carnivores frequented the area to hunt in groups or individually. 展开更多
关键词 Trampled Surface Dinosaurs Locomotion Behavior Lower Cretaceous Cape Espichel PORTUGAL IBERIA
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Monitoring of Ultrafine Particles in the Surrounding Urban Area of In-Land Passenger Ferries
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作者 Margarida Lopes Ana Russo +1 位作者 Célia Gouveia Francisco Ferreira 《Journal of Environmental Protection》 2019年第6期838-860,共23页
Maritime transportation, widely used both in international transport of goods and touristic purposes, has been identified as a significant source of ultrafine particles (UFP). In-land passenger ferry is a source of UF... Maritime transportation, widely used both in international transport of goods and touristic purposes, has been identified as a significant source of ultrafine particles (UFP). In-land passenger ferry is a source of UFP far less addressed;however, in locations with relatively high frequency of this transportation mode, it is expected that they contribute to an increase of their concentration. Moreover, the negative effects of UFP on human health and environment are known and therefore, monitoring UFP produced by ferries is vital to assess the degree of exposure of who work or live close to ferries’ terminals or downwind to their cruising path. This work aims to study the influence of in-land ferries activities on UFP in the urban/suburban areas near ferries’ terminals and downwind across the cruising path. The UFP monitoring campaign was carried out from September to December 2018 for 19 non-consecutive periods. The sampling sites were chosen in order to maximize measurements under downwind conditions and allow the association between ferry operation and UFP concentration response. Based on data collected, correlation analysis was performed between ferry’s traffic and particle number counting (PNC) of UFP, and also with meteorological variables. Results show an increase in PNC ranging from 25 to 197% during the third minute around a ferry movement and are moderate to positive significant correlations between PNC values and the number of ferry operations (r = 0.79 to r = 0.94), showing that UFP emitted by in-land ferries contributes to PNC increase. Moreover, negative correlations (r = -0.85 to r = -0.93) between PNC and wind intensity were also found. 展开更多
关键词 Air Pollution PNC In-Land PASSENGER FERRIES MONITORING Campaign Health
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Optimization of a photovoltaic-battery system using deep reinforcement learning and load forecasting 被引量:1
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作者 António Corte Real G.Pontes Luz +2 位作者 J.M.C.Sousa M.C.Brito S.M.Vieira 《Energy and AI》 EI 2024年第2期168-183,共16页
Home Energy Management Systems(HEMS)are increasingly relevant for demand-side management at the residential level by collecting data(energy,weather,electricity prices)and controlling home appliances or storage systems... Home Energy Management Systems(HEMS)are increasingly relevant for demand-side management at the residential level by collecting data(energy,weather,electricity prices)and controlling home appliances or storage systems.This control can be performed with classical models that find optimal solutions,with high real-time computational cost,or data-driven approaches,like Reinforcement Learning,that find good and flexible solutions,but depend on the availability of load and generation data and demand high computational resources for training.In this work,a novel HEMS is proposed for the optimization of an electric battery operation in a real,online and data-driven environment that integrates state-of-the-art load forecasting combining CNN and LSTM neural networks to increase the robustness of decisions.Several Reinforcement Learning agents are trained with different algorithms(Double DQN,Dueling DQN,Rainbow and Proximal Policy Optimization)in order to minimize the cost of electricity purchase and to maximize photovoltaic self-consumption for a PV-Battery residential system.Results show that the best Reinforcement Learning agent achieves a 35%reduction in total cost when compared with an optimization-based agent. 展开更多
关键词 Energy management system Deep reinforcement learning Demand-side management Load forecasting Deep learning Energy storage systems
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Insights into the origin of precipitation moisture for tropical cyclones during rapid intensification process
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作者 Albenis Perez-Alarcon Jose C.Fernandez-Alvarez +2 位作者 Ricardo M.Trigo Raquel Nieto Luis Gimeno 《Tropical Cyclone Research and Review》 2024年第2期72-87,共16页
In this study,we identified the moisture sources for the precipitation associated with tropical cyclones(TCs)during the rapid intensification(RI)process from 1980 to 2018 by applying a Lagrangian moisture source diagnos... In this study,we identified the moisture sources for the precipitation associated with tropical cyclones(TCs)during the rapid intensification(RI)process from 1980 to 2018 by applying a Lagrangian moisture source diagnostic method.We detected sixteen regions on a global scale for RI events distributed as follows:four in the North Atlantic(NATL),two in the Central and East Pacific Ocean(NEPAC),the North Indian Ocean(NIO)and South Indian Ocean(SIO),and three in the South Pacific Ocean(SPO)and the Western North Pacific Ocean(WNP).The moisture uptake(MU)mostly was from the regions where TCs underwent RI.The Western NATL,tropical NATL,Caribbean Sea,the Gulf of Mexico and the Central America and Mexico landmass supported~85.4%of the precipitating moisture in the NATL,while the latter source and the eastern North Pacific Ocean provided the higher amount of moisture in NEPAC(~84.3%).The Arabian Sea,the Bay of Bengal and the Indian Peninsula were the major moisture sources in NIO,contributing approximately 81.3%.The eastern and western parts of the Indian Ocean supplied most of the atmospheric humidity in SIO(~83.8%).The combined contributions(~87.9%)from the western and central SPO and the Coral Sea were notably higher in SPO.Meanwhile,TCs in the WNP basin mostly received moisture from the western North Pacific Ocean,the Philippine Sea and the China Sea,accounting for 80.1%.The remaining moisture support in each basin came from the summed contributions of the remote sources.Overall,RI TCs gained more moisture up to 2500 km from the cyclone centre than those slow intensification(SI)and the total MU was approximately three times higher during RI than SI.Finally,the patterns of the MU differences respond to the typical pathways of moisture transport in each basin. 展开更多
关键词 Tropical cyclones Rapid intensification Moisture sources PRECIPITATION Lagrangian moisture tracking
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The first high spatial resolution multi-scale daily SPI and SPEI raster dataset for drought monitoring and evaluating over China from 1979 to 2018 被引量:2
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作者 Rongrong Zhang Virgílio A.Bento +6 位作者 Junyu Qi Feng Xu Jianjun Wu Jianxiu Qiu Jianwei Li Wei Shui Qianfeng Wang 《Big Earth Data》 EI CSCD 2023年第3期860-885,共26页
Standardized Precipitation Index(SPI)and Standardized Precipitation Evapotranspiration Index(SPEI),traditionally derived at a monthly scale,are widely used drought indices.To overcome temporalresolution limitations,we... Standardized Precipitation Index(SPI)and Standardized Precipitation Evapotranspiration Index(SPEI),traditionally derived at a monthly scale,are widely used drought indices.To overcome temporalresolution limitations,we have previously developed and published a well-validated daily SPI/SPEI in situ dataset.Although having a high temporal resolution,this in situ dataset presents low spatial resolution due to the scarcity of stations.Therefore,based on the China Meteorological Forcing Dataset,which is composed of data from more than 1,000 ground-based observation sites and multiple remote sensing grid meteorological dataset,we present the first high spatiotemporal-resolution daily SPI/SPEI raster datasets over China.It spans from 1979 to 2018,with a spatial resolution of 0.1°×0.1°,a temporal resolution of 1-day,and the timescales of 30-,90-,and 360-days.Results show that the spatial distributions of drought event characteristics detected by the daily SPI/SPEI are consistent with the monthly SPI/SPEI.The correlation between the daily value of the 12-month scale and the monthly value of SPI/SPEI is the strongest,with linear correlation,Nash-Sutcliffe coefficient,and normalized root mean square error of 0.98,0.97,and 0.04,respectively.The daily SPI/SPEI is shown to be more sensitive to flash drought than the monthly SPI/SPEI.Our improved SPI/SPEI shows high accuracy and credibility,presenting enhanced results when compared to the monthly SPI/SPEI.The total data volume is up to 150 GB,compressed to 91 GB in Network Common Data Form(NetCDF).It can be available from Figshare(https://doi.org/10.6084/m9.figshare.c.5823533)and ScienceDB(https://doi.org/10.57760/sciencedb.j00076.00103). 展开更多
关键词 Drought index climate change climatic disaster Generalized Extreme Value
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3D City Models as a Visual Support Tool for the Analysis of Buildings Seismic Vulnerability: The Case of Lisbon 被引量:1
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作者 Paula Redweik Paula Teves-Costa +1 位作者 Inês Vilas-Boas Teresa Santos 《International Journal of Disaster Risk Science》 SCIE CSCD 2017年第3期308-325,共18页
3D city models associate a database of a city to a rigorous geospatial representation that is close to the visible reality by combining appearance, geometry, and semantics. As such, these models may include tools that... 3D city models associate a database of a city to a rigorous geospatial representation that is close to the visible reality by combining appearance, geometry, and semantics. As such, these models may include tools that convey attribute analysis, not only at the statistical level but also in terms of visual appearance of the objects, thus allowing the generation of new knowledge about a phenomenon or its effects. Lisbon is a city with a moderate level of seismic risk, and has been hit in the past by strong earthquakes. Several seismic vulnerability studies of buildings have been carried out in Lisbon. These studies generate different scenarios that consider the magnitude and source location of potential earthquakes. The results of these studies were presented as maps obtained from crossing information contained in 2D layers and presented in a GIS environment. In the present study a seismic vulnerability assessment of Lisbon's buildings held in 2D is extended to the third dimension, which refines the resolution and the set of parameters and explores the gains of spatial analysis in 3D representations. The numerous parameters that contribute to assess seismic vulnerability of buildings may be analyzed individually or simultaneously as well as in multiple seismic scenarios. Although covering all residential buildings in Lisbon, the application of the 3Dcity model is demonstrated with more detail in three pilot areas. 展开更多
关键词 3D-GIS 3D models Building vulnerability Lisbon Seismic scenarios
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Magmatic Evolution of Garnet-Bearing highly Fractionated Granitic Rocks from Macao,Southeast China:Implications for Granite-Related Mineralization Processes
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作者 Pedro Quelhas João Mata Ágata Alveirinho Dias 《Journal of Earth Science》 SCIE CAS CSCD 2021年第6期1454-1471,共18页
The widespread W-(Mo)-Sn-Nb-Ta polymetallic mineralization in Southeast(SE)China is genetically associated with Mesozoic highly fractionated granitic rocks.Such rocks have enigmatic mineralogical and geochemical featu... The widespread W-(Mo)-Sn-Nb-Ta polymetallic mineralization in Southeast(SE)China is genetically associated with Mesozoic highly fractionated granitic rocks.Such rocks have enigmatic mineralogical and geochemical features,making its petrogenesis an intensely debated topic.To better understand the underlying magma evolution processes,petrography,garnet chemistry and whole-rock major and trace element data are reported for Jurassic highly fractionated granitic rocks and associated microgranite and aplitepegmatite dikes from Macao and compared with coeval similar granitic rocks from nearby areas in SE China.Despite the fact that the most evolved rocks in Macao are garnet-bearing aplite-pegmatite dikes,the existence of coeval two-mica and garnet-bearing biotite and muscovite granites displaying more evolved compositions(e.g.,lower Zr/Hf ratios)indicates that the differentiation sequence reached higher degrees of fractionation at a regional scale.Although crystal fractionation played an important role,late-stage fluid/melt interactions,involving F-rich fluids,imparted specific geochemical characteristics to Macao and SE China highly fractionated granitic rocks such as the non-CHARAC(CHArge-and-RAdius-Controlled)behavior of trace elements,leading,for example,to non-chondritic Zr/Hf ratios,Rare Earth Elements(REE)tetrad effects and Nb-Ta enrichment and fractionation.Such process contributed to the late-stage crystallization of accessory phases only found in these highly evolved facies.Among the latter,two populations of garnet were identified in MGI(Macao GroupⅠ)highly fractionated granitic rocks:small grossular-poor euhedral grains and large grossular-rich skeletal garnet grains with quartz inclusions.The first group was mainly formed through precipitation from highly evolved Mn-rich slightly peraluminous melts under low-pressure and relatively low temperature(~700℃)conditions.Assimilation of upper crust metasedimentary materials may have contributed as a source of Mn and Al to the formation of garnet.The second group has a metasomatic origin related to the interaction of magmatic fluids with previously crystallized mineral phases and,possibly,with assimilated metasedimentary enclaves or surrounding metasedimentary strata.The highly fractionated granitic rocks in Macao represent the first stage in the development of granite-related W-(Mo)-Sn-Nb-Ta mineralization associated with coeval more evolved lithotypes in SE China. 展开更多
关键词 highly fractionated granites aplite Macao(South China) JURASSIC late-stage fluid/melt interactions GARNET non-CHARAC REE tetrad effect
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Risk Governance,Assessment,and Economic Impacts
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作者 Paula Teves-Costa JoséManuel Mendes 《International Journal of Disaster Risk Science》 SCIE CSCD 2017年第3期235-236,共2页
Due to climate change,growing urbanization,and population migration the social and economic impacts of natural hazards have been increasing worldwide.The challenge for risk science,both methodologically and conceptual... Due to climate change,growing urbanization,and population migration the social and economic impacts of natural hazards have been increasing worldwide.The challenge for risk science,both methodologically and conceptually,is to integrate robust multi-hazard evaluation models with 展开更多
关键词 Risk Governance Assessment and Economic Impacts
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