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1.
Mary Anning, Alfred Nicholson Leeds and Steve Etches form part of a long line of individuals who furnished a substantial addition to our understanding of marine and terrestrial ecosystems through collecting significant numbers of superb fossils. For all three collectors, fossils became a factor that dominated their lives, and their fossil collecting led to the discovery of numerous taxa new to science. Extensive collecting was made possible by the fortunate circumstances of living ‘in the right place at the right time’, close to fine-grained UK Jurassic deposits (Lagerstätten) with well-preserved large Jurassic marine reptiles. All three were highly-motivated and developed a considerable skill sets for discovering, collecting, preparing, conserving and displaying fossils. They developed personal and professional interactions with family and friends, and university and museum professionals, although their collecting resulted in variable recognition of their work. Each collector can be considered a complex mix of amateur and professional: Mary Anning, a professional fossil collector and amateur palaeontologist; Alfred Leeds transitioned from amateur to professional fossil collector, but remained an amateur palaeontologist; and Steve Etches has remained an amateur fossil collector and palaeontologist. However, all three exhibited an entirely professional outlook to collecting, and should be considered professionals of the highest degree. The impact of Mary Anning, Alfred Nicholson Leeds and Steve Etches has been critical for the development of Palaeontology as a science, and without whom palaeontology, with all its associated benefits to a wide scientific and non-scientific audience, would not be as rich as we currently know it.  相似文献   

2.
There is (or should be) an archived specimen, a reference copy if you like, for all living and fossil species that have been described scientifically. These physical specimens, so‐called name‐bearing type specimens, are housed at museums or academic institutes around the world for researchers to study and perhaps compare with their own material. But what about our own species, Homo sapiens?  相似文献   

3.
通过在河套平原五原地区建立典型剖面,对从剖面上采集的水样进行测试分析,结合地质环境特征,得出五原剖面上各地质、地貌单元条件下砷在浅层地下水的赋存形态。应用美国地质调查局专业水文地球化学软件Phreeqc进行水文地球化学模拟,对五原地区地下水Fe-As-H2O体系中砷的吸附释放趋势进行讨论,得出五原剖面上扇前洼地砷酸盐主要表现为从羟基铁上解离释放出来;而黄河冲湖积平原地下水中As主要表现为在水中解离。黄河冲湖积平原地下水中Fe(OH)3对砷释放的抑制力远远高于扇前洼地。  相似文献   

4.
Bose  Pablo S. 《GeoJournal》2020,87(2):195-207

What does it mean to conduct community-based and praxis-oriented research at a time when those whose lives you study and with whom you work are the subjects of increasing levels of xenophobia, marginalization, and demonization? How does one conceive of research ethics, of the relationship between the roles of scholars, teachers, and citizens in light of such dynamics? In what ways can scholarship help to intervene in the world around us, in particular to improve the perception and amplify the voices of marginalized groups and individuals? This paper considers these issues in the context of research ethics and the growing field of community geography. I draw in particular on an example from a multi-year study of refugee resettlement in non-traditional destinations across the US. When the study began, refugee policies and settlement patterns were little known to the general public in the US. Since then, refugees and migration more broadly have become increasingly prominent and controversial worldwide. In this paper I explore some of the challenges regarding collaborations between university researchers and community partners, highlighting the tensions exposed through the use of the visualization technique known as Photovoice, meant to provide alternative perspectives on ideas for urban change amongst participants. I also consider some ideas for steps to address these challenges, including the building of networks and training for researchers and formalized partnership processes for community groups.

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5.
煤矿地质测量空间信息系统及其发展趋势   总被引:7,自引:1,他引:6  
分析了我国煤矿地质测量空间信息系统的研发和应用现状,并从信息采集的多源化、管理的网络化、决策支持的智能化,以及与其他专业系统集成化的角度,分析了煤矿地质测量空间信息系统发展的趋势。   相似文献   

6.
用VC++语言开发一种测井解释系统。该系统运行在单机环境中 ,其界面友好 ,功能灵活 ,用户可快速熟悉系统 ,轻松使用 ;该系统能综合进行小型数据的各种测井解释工作 ,数据量太大时则分割后再进行解释。本系统为专业人员提供了一种新的测井解释工具。  相似文献   

7.
This study explores the influence of three factors on a person’s decision to drive in winter weather: destination, affected area, and caution level. Participants (n = 555) completed an online survey that included scenarios with text of a simulated radio message involving a character named Mike. After the scenario, participants answered Likert-scaled questions related to their intention to drive (what would you do) and their recommended behavior for others (what should Mike do). There was a significant effect of destination and caution level on the decision to drive. Participants were more likely to respond that they would drive if the destination was work rather than dinner, and if the caution statement was “exercise caution” rather than “do not drive.” There were similar significant effects of destination and caution level on what the scenario character should do. It is recommended that a clear directive be included in warning messages to encourage drivers to stay off the roadways during hazardous weather.  相似文献   

8.
基于WebGIS的土地信息发布技术   总被引:1,自引:0,他引:1  
介绍了WebGIS的几种运行模式,分析了网上发布图件的技术和土地信息自身的特点。网上土地信息发布的关键是相关图件的网上传输,且传输的图件应能够实现客户端的地图显示、放大、缩小、平移、漫游、多种选择查询及缓冲区分析、数据编辑等功能,要实现这一功能,必须实现图件的矢量传输,但是,土地信息的相关图件的数据量大,传输时间长。因此,本文对一些相关的技术作了一些研究。  相似文献   

9.
The non-LTE sodium abundances of 100 stars with metallicities ?3<[Fe/H]<0.3 are determined using high-dispersion spectra with high signal-to-noise ratios. The sodium abundances [Na/Fe] obtained are close to the solar abundance and display a smaller scatter than values published previously. Giants (logg<3.8) with [Fe/H]g>3.8) with metallicities ?2<[Fe/H]相似文献   

10.
Stable isotopic data of meteorites are critical for understanding the evolution of terrestrial planets. In this study, we report high-precision vanadium (V) isotopic compositions of 11 unequilibrated and equilibrated L chondrites. Our samples show an average δ51V of ??1.25‰?±?0.38‰ (2SD, n?=?11), which is ~?0.5‰ lighter than that of the bulk silicate Earth constrained by mantle peridotites. Isotopic fractionation in type 3 ordinary chondrites vary from ??1.76‰ to ??1.29‰, whereas the δ51V of equilibrated chondrites vary from ??1.37‰ to ??1.08‰. δ51V of L chondrites do not correlate with thermal metamorphism, shock stage, or weathering degree. Future studies are required to explore the reason for V isotope variation in the solar system.  相似文献   

11.
文中收集了全球太古宙TTG 和后太古宙埃达克岩的数据,研究对比表明,太古宙TTG 不同于埃达克岩,早先学术界认为太古宙TTG 相当于现代的埃达克岩,是一个错误的见解,是一个伪命题。TTG 术语最早出现时并没有类似于埃达克岩的见解,后来发现了埃达克岩才引出二者类似的认识。为什么会出现这种见解?推测有两种可能:1)早先的研究均来自抽样的研究,即从典型到一般的推理方法。但是,抽样研究可能没有代表性。2)TTG平均值的误导,TTG 的Sr的平均值的确>400×10-6,相当于埃达克岩,但是,通过分析TTG 全球数据表明,TTG 中的Sr含量变化很大,与埃达克岩没有关系。TTG 主要出现在太古宙,后太古宙很少;TTG 是太古宙岩石地壳的主体;而埃达克岩主要出现在后太古宙,是火山岩中很少的类型。这表明,TTG 和埃达克岩分别处于不同的构造体制。太古宙异常的热,可能还没有板块构造。太古宙的岩浆岩(包括TTG)即使与后太古宙某些岩浆岩具有类似的地球化学特征,可能也不能照搬现代板块构造的解释。  相似文献   

12.
张仲石  李双林  王会军  郭正堂 《地球科学》2022,47(10):3569-3579
随着新一轮的科技革命蓬勃兴起,大气科学学科正步入地球系统科学的新时代,学科交叉必然产生新的增长点.大气科学的发展经历了观测-理论-模型的三个阶段,很好地践行了“数据-模式驱使科学”的研究范式.然而,地质学具有更深远的时空复杂性,需要更长时间的数据积累.目前,地质学正面临着研究范式由观测向理论和模型的转变.大气科学与地质学的交叉将为这一转变提供经验和启示.同时,大气科学与地质学的交叉,需要研究气候系统上边界(大气顶的太阳辐射)和下边界(固体地球形态)变化导致的大气和海洋环流的响应.研究这些问题,将成为发展同时统辖“分钟、小时”直至“地史”的时间尺度的大气科学理论的关键,也是未来地球系统模式发展的重要方向之一.中国地质大学(武汉)的大气科学专业,作为推动大气科学与地质学交叉的排头兵,任重而道远.   相似文献   

13.
The behavior and dynamics of arsenic at Ilha do Mel, Guaraque?aba, and Paranaguá, located in the Paranaguá Estuarine Complex, Brazil, were investigated in this work. Samples were collected in March, September, and December of 2005. With respect to arsenic behavior, the total concentrations were higher for Paranaguá (22.5?±?2.5?μg?L?1) on average, followed by the samples of Guaraque?aba (14.4?±?3.2?μg?L?1) and Ilha do Mel (8.7?±?1.1?μg?L?1). The concentrations found in this work were consistently greater when compared to other estuaries. The results can be attributed to geological factors. Nevertheless, it was also possible to realize that higher concentrations were found in Paranaguá, the more impacted environment. These results represent a strong indication that human activities in the area contribute to the enrichment of the estuary with this metalloid. Arsenic was mainly present in the dissolved phase, which corresponded to more than 70% of the total concentration. This behavior can represent a greater residence time of this metalloid in the water column. The marine phytoplankton presence was decisive in dictating the distribution of As in the waters of Paranaguá estuary. Organic species, which are considered the less toxic, were found in higher concentrations in the eutrophic areas such as Guaraque?aba and Paranaguá. This was a typical behavior during the summer probably due to higher biological activity.  相似文献   

14.
《Gondwana Research》2014,25(3-4):807-814
For several decades geoscientists have recognised intraplate tectonic activity far from plate margins, both from modern and ancient examples. This apparent disconnect with the drivers of plate tectonics does not necessarily imply unconnected processes, but rather an uncertainty in understanding exactly how these systems operate. Are the driving forces derived locally or do they propagate from plate-margins? How do these forces interact with a complex tectonic inheritance to generate the observed tectonism? Furthermore, what novel approaches have been applied to understand these processes? Here we review the general literature and the contents of this special issue to develop some partial answers to these questions. Key observations include the critical importance of local lithospheric heterogeneities as a control on the mode of orogenesis, and also the role of locally derived forces from mantle upwelling or from depositing thick piles of magmatic or sedimentary rocks. These processes happen within the overarching tectonic setting provided by far-field plate margins, which show intimate links in both time and observed processes with many intraplate regions. These insights would not be possible without a growing arsenal of geological, geophysical and numerical methods that can be applied to intraplate regions, and this is reflected in the varied approaches within the issue. We envisage that this special issue will provide a stimulus for further progress in understanding intraplate tectonics.  相似文献   

15.
Environmental isotopes data of oxygen and hydrogen of natural water and sulphur and oxygen of dissolved sulphate as well as characteristics of d-excess are used to illustrate the salinity origin in Kert aquifer NE Morocco. In this study, 14 groundwater samples and surface water of the Kert River were collected in the Kert plain during December 2008, and were combined with previously collected hydrochemical data. The isotope compositions of these waters range from ?5.74 to ?4.51 ‰ for oxygen and from ?40.8 to ?34.1 ‰ for hydrogen. In Kert River these values are ?6.47 ‰ for oxygen and ?47.56 ‰ for hydrogen. All the samples with a slope <8 do not fall on the meteoric water line indicating a light evaporation. Water has low and different d-excess values (ranging from +1.37 to +9.82 ‰), reflecting different climatic conditions. Based on the nitrate concentration water in the Kert aquifer comes from the modern precipitation. The isotope compositions range from ?2.2 to +16 ‰ for sulphur and from +5.02 to +13.86 ‰ for oxygen. In Kert River these values are ?4.6 and +5.3 ‰ for sulphur and oxygen, respectively. There are fairly constant difference between oxygen of water and the oxygen of sulphate suggesting a dominant control of this latter in sulphate sources. At least three major sulphate sources were identified by the isotope data from sulphate in these waters: (1) dissolved marine sulphate from the underlying upper Miocene unit; (2) dissolved sulphate from Kert River; (3) sulphate derived from oxidation of sulphur compounds in the metamorphic massif of Temsamane. The latter has a dilution role. The isotopic variations of these waters and sulphate concentration therein reflect mixing of these sources in the aquifer.  相似文献   

16.
The Itajaí Basin located in the southern border of the Luís Alves Microplate is considered as a peripheral foreland basin related to the Dom Feliciano Belt. It presents an excellent record of the Ediacaran period, and its upper parts display the best Brazilian example of Precambrian turbiditic deposits. The basal succession of Itajaí Group is represented by sandstones and conglomerates (Baú Formation) deposited in alluvial and deltaic-fan systems. The marine upper sequences correspond to the Ribeir?o Carvalho (channelized and non-channelized proximal silty-argillaceous rhythmic turbidites), Ribeir?o Neisse (arkosic sandstones and siltites), and Ribeir?o do Bode (distal silty turbidites) formations. The Apiúna Formation felsic volcanic rocks crosscut the sedimentary succession. The Cambrian Subida leucosyenogranite represents the last felsic magmatic activity to affect the Itajaí Basin. The Brusque Group and the Florianópolis Batholith are proposed as source areas for the sediments of the upper sequence. For the lower continental units the source areas are the Santa Catarina, S?o Miguel and Camboriú complexes. The lack of any oceanic crust in the Itajaí Basin suggests that the marine units were deposited in a restricted, internal sea. The sedimentation started around 600?Ma and ended before 560?Ma as indicated by the emplacement of rhyolitic domes. The Itajaí Basin is temporally and tectonically correlated with the Camaqu? Basin in Rio Grande do Sul and the Arroyo del Soldado/Piriápolis Basin in Uruguay. It also has several tectono-sedimentary characteristics in common with the African-equivalent Nama Basin.  相似文献   

17.
倾斜CCP道集抽取方法及影响因素分析   总被引:3,自引:0,他引:3  
界面上三维PS波(反射转换横波)的转换点在地表有相应的界面法向投影点,抽取CCP (共转换点)道集的实质就是确定不同方位上投影点距离炮点和对应检波点的比例关系。当界面倾斜时,该比例关系是界面的倾角、倾向、法向深度、炮检方位以及纵横波速度比等参数的函数。就上述参数通过这一比例关系是如何影响共转换点道集的构成及影响程度设计了特定的模型进行讨论。计算结果表明,忽视倾斜界面的影响将引起转换波抽道集的混乱,并造成后期成像的错误。   相似文献   

18.
冯美贵  翁炜  蒋睿 《探矿工程》2019,46(6):53-58
针对机械式扩底钻具存在扩孔与取土、清孔分离,工序复杂,孔内沉渣难以清理干净,施工效率低,扩孔质量、精度无法保证等问题,研制了机电液一体化集土式扩底钻机具。重点研究集土式扩底钻进施工工艺,集土式扩底钻具的机械结构设计、液压系统和电气控制系统设计,并进行机电液一体化集成试验。结果表明机电液一体化集土式扩底钻机具集扩孔、集土功能于一体,扩底直径准确、扩孔精度高,减少工艺步骤,提高工作效率,满足旋挖钻进扩底桩的施工需求,实现智能化扩底钻进。  相似文献   

19.
This paper presents the findings of a case-study carried out on the Maasai herbalists of Arusha town, whose social and economic situation, both in their villages of origin and in town is being analysed. Special emphasis is laid on the struggle of women herbalists to upgrade their low economic and social status in their home villages and, at the same time, satisfy their most basic needs in town. In this, they depend on their asset of indigenous ethnomedical knowledge, which they commercialise. They do not consider themselves professional experts among their own people, but they become ones when they are in town. A major aim of this paper is also to illustrate the wealth of indigenous knowledge concerning the biodiversity of people's environment. A survey of the medical plants most frequently sold by the herbalists is presented with the intention of identifying those species which are endangered, although the herbalists themselves do not yet perceive the seriousness of the situation. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

20.
Jessica Dempsey 《Geoforum》2011,42(2):211-221
Environmental politics, argues French philosopher Bruno Latour, have been a ‘disappointment’. Rather than trying to bring environmental concerns into a political world split into two - between Nature/Science and politics/society - Latour argues that environmental movements ought to focus on destroying this two-house collective, and develop ‘an understanding of ecological crises that no longer uses nature to account for the tasks to be accomplished’. In this paper I put my research on the politics and science of the Great Bear Rainforest (GBR), a large tract of temperate rainforest on the central and north coast of British Columbia, into direct conversation with Latour’s arguments about science, epistemology and environmental politics. The GBR was a site of intense political struggle focused predominantly on the scale and scope of industrial forestry, a struggle which ‘ended’ in 2006 with what some call a historic compromise between some high-profile environmental groups, First Nations, the Provincial government, and the forest industry. This paper focuses on two interlinked questions: do the environmental organizations at the centre of the struggle demonstrate the maladies identified by Latour; are they too preoccupied with representing Nature through Science? And second, do these maladies help us explain or understand the politics over the GBR? Were the politics of the GBR limited by environmentalist invocations of a singular Nature through Science, what Latour calls ‘Naturpolitik’? The encounter between theory and practice leads to a more cautious and critical assessment of the environmental politics in the GBR, but also tempers Latour’s arguments. Environmentalists in the GBR do exhibit Latour’s maladies, but in tracing the Politics of Nature there, it seems that Naturpolitik is not as powerful as Latour argues.  相似文献   

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