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1.
A partial, isolated tooth from the Middle Jurassic (Bathonian) Stonesfield ‘slate’ of the Taynton Limestone Formation of Oxfordshire is identified as likely coming from a ctenochasmatid pterosaur. Referral to Ctenochasmatidae is based on its very slender, slightly curved crown with near circular cross-section and subparallel margins, slightly inflated root and its stratigraphic age. The tooth is part of the William Smith fossil collection held at the Natural History Museum, London. The collection was assembled as part of William Smith's attempt to identify and map strata around England and Wales in the last decade of the 18th century and the first 15 years of the 19th century. Smith's extensive fossil collection of more than 2500 specimens was purchased by the British Museum in 1816 (Wigley et al., 2018), and thus the specimen is the first pterosaur to be accessioned to the national collection. 相似文献
3.
The earthquake catalogue of the European area, 1901–1985, with unified magnitudes, has been used for the preparation of epicentre maps of the Mediterranean area. Epicentres have been plotted on three sheets for different magnitude ranges, M
B
(or m
B
) 5, 0, M
S
(or m
B
) = 4.4–4.9, M
S
(or m
B
) 4.3, according to the estimated levels of homogeneity. The first map ( M 5) enables an objective comparison of seismicity over the whole Mediterranean area. The other two maps are complementary without the guarantee of completeness. Epicentres define the position of principal earthquake zones and levels of earthquake activity. The maps also serve as the starting point for further data processing. Graphs illustrating the time variation of earthquake activity in the whole area and the mean magnitude-frequency relationships are included. 相似文献
4.
Summary The question of alternative technologies for high-speed Internet access lies at the heart of rural development problems. In
this paper, we focus on one of those technologies, the system combining satellite technologies and Wi-Fi. Based on an empirical
study carried out in three rural areas, we analyze the dynamics of the use and appropriation of that technology by the companies
and organizations participating in the experiment. Considered both from a technical and social standpoint, the technology
‘in use’ appears here in its structuring dimensions.
相似文献
6.
This paper argues that the metaphorical figure of the island plays an important but profoundly ambiguous role in the imagination of social space. The paper argues that ‘utopic’ islands have historically provided a fictional domain of experimentation that has informed the constitution of ‘real’ state spaces. From the 16th to 20th centuries this took the form of an increasingly consolidated and ‘global’ endotopia: a world, exemplified by the ‘political’ map, full of state spaces constituted as interiors. More recently, islands have served a very different metaphoric function, being used to create and legitimise spaces of exteriority – ‘xenospaces’ such as the online worlds of the ‘metaverse’ and the arcane legal/financial spaces of offshore – which in combination constitute an emergent xenotopia. The ‘philosopher’s island’ (Mackay, 2010), therefore, represents a complex and polyvalent spatial form that serves to continuously and expediently redefine the nature of social space. 相似文献
7.
The ‘just transition’ is a concept receiving more attention in the literature to-date. This critical review discusses this and how there are overlaps with literature on energy, environmental and climate justice. Within the separate energy, environment and climate change scholar communities, there is too much distortion of what the ‘transition’ means and what ‘justice’ means, and they all should be understood within the just transition concept. To increase public understanding and public acceptance of a just transition, these research communities need to unite rather than continue alone. 相似文献
8.
The Sa''al Metamorphic Complex (SMC; southern Sinai) encompasses the oldest arc rocks in the Arabian–Nubian Shield, comprising two non-consanguineous metavolcanic successions (the Agramiya Group and the Post-Ra''ayan Formation) separated by the metasediments of the Ra''ayan Formation. It experienced three distinct deformational events (D1–D3) and two low-medium grade regional metamorphic events (M1–M2). The Agramiya Group and the Ra''ayan Formation experienced all tectonometamorphic events (D1–D3 and M1–M2), whereas the Post-Ra''ayan volcanic rocks were only affected by the D3 and M2 events. D1 is an extensional event and is connected to the late Rodinia break-up (~Tonian; 900–870 Ma). The M1 metamorphism variably affected the older Agramiya Group, the rhyolitic tuffs experiencing lower to upper greenschist facies conditions and the basic and intermediate volcanic rocks undergoing amphibolite facies metamorphism. The Ra''ayan Formation metasediments experienced upper greenschist to amphibolite facies metamorphism. The upper greenschist facies M2 affected the youngest Post-Ra''ayan volcanic rocks and other stratigraphic successions. The compressive D2 and D3 events were coeval with the accretion of dismembered terranes in the assembly of Gondwana. D2 can be linked to the Tonian–Cryogenian arc-arc assembly (~880–760 Ma; in Elat and Sinai), whereas D3 and the accompanying M2 is constrained to 622–600 Ma (Ediacaran). 相似文献
9.
We discuss issues related to a recognised shortcoming in existing tsunami hazard assessments for Pacific Island Countries and Territories (PICTs), that of tsunamigenic slope failures (TSFs). Currently, TSFs are most likely underrepresented as sources in existing tsunami databases for two key reasons. First, relatively low magnitude earthquakes associated with subduction zones are generally assigned as the tsunamigenic source, as opposed to the TSFs they generate. A reassessment of such ‘anomalous tsunamis’ may yield clues that serve to reassign their tsunamigenic source. Second, there are thousands of oceanic islands and seamounts scattered across the Pacific and flank collapse of volcanic edifices such as these is a largely unquantified tsunamigenic threat. However, while it is now possible to model such TSFs, this is unlikely to happen in the near future because of the lack of detailed bathymetry and landslide mass data. Recent developments in the identification of past tsunamis in the Pacific Islands have developed a unique range of indicators that can be used for identifying such events. These are geological, oral tradition and archaeological components that include, but are not limited to, a modified Darwinian model of atoll formation, coastal megaclasts, oral traditions of vanished islands and giant waves, and the abandonment of prehistoric coastal sites. As such, the most logical way forward is to use the multiple indicators available to us to identify evidence of past tsunamis. 相似文献
10.
As emerging sources of so-called ‘big data’ are increasingly utilized in order to understand social and spatial processes, so too have these new data sources become the subject of harsh criticism from more critically-oriented geographers and social scientists. This paper argues that one of the major issues preventing a more productive dialogue between critical human geographers and those already engaging in the mapping and analysis of these new data sources is around the ways that space and spatiality are conceptualized in social media mapping. As such, this paper draws on and extends earlier critiques of the ‘spatial ontology of the geotag’, in which the geographic analysis of geotagged social media data over-privileges the single latitude/longitude coordinate pair attached to each individual data point, often leading to the kind of simplistic mappings and interpretations prevalent today. The goals of this paper are two-fold: first, to demonstrate how the spatial ontology of the geotag is implicitly operationalized within mainstream social media mapping exercises, and how this understanding of space remains incongruent with existing conceptions of space drawn from human geography. Second, using the example of tweeting in the wake of the August 2014 killing of an unarmed African–American teenager by a police officer in Ferguson, Missouri, this paper demonstrates how a more geographically-situated analysis of this kind of data, inspired by relational or multidimensional conceptualizations of space, can yield alternative understandings of the social processes embedded in such data. 相似文献
11.
Scale is a debatable term in the humanities and social sciences. Conceptualized in human geography as spatial categories of thought, as the arenas where social processes occur, as bounded political-economic frames or as unhelpful binaries privileging either the local or the global, scale intersects a significant body of geographical research. The unfolding and intermeshing of topological connections that help to share moments and experiences are important sources for the differentiation, renewal and recalibration of individual identities, but they often work as co-components to scalar identifications. Engaging with the recent discussion on scale and the upsurge of emotional geographies, I seek to understand how people contextualize space through situated scalar perspectives and how they realign and recognize their identities through embodied emotions. The analysis of the empirical material, that comprises 23 focus groups with locally and universally-orientated civic organizations in Finland and England, focuses on the ways people use landscapes and communities as emotional signposts in their scalar identification. I argue that scale is a situated category, whose spectrum individuals negotiate through the performance of social discourses and cultural practices. In such negotiation, people scale their identity narratives to overcome or emphasize the distinctions between ‘us’ and ‘others’. 相似文献
13.
Palaeogene sediments of the Hampshire Basin were a sensitive recorder of fluctuations in climate and eustatic sea level as Earth's climate transitioned from the global early Eocene ‘hothouse’ to the early Oligocene ‘coolhouse’, accompanied by the first permanent continent-scale glaciation of Antarctica at the Eocene/Oligocene boundary. A study of the Palaeogene sediments of the Hampshire Basin is not only interesting from a palaeoclimate perspective, but the marine middle Eocene formations are renowned for containing some of the most abundant and diverse Palaeogene fossil assemblages in the world. In this article, I take you on a tour of the geological evolution of the Hampshire Basin from the end of the Paleocene through to the Pleistocene. I highlight some of the best exposures where sediments can be studied at outcrop and representative fossil assemblages can be collected, along with the economic and archaeological significance of these Palaeogene sediments. 相似文献
14.
Digital social data are now practically ubiquitous, with increasingly large and interconnected databases leading researchers, politicians, and the private sector to focus on how such ‘big data’ can allow potentially unprecedented insights into our world. This paper investigates Twitter activity in the wake of Hurricane Sandy in order to demonstrate the complex relationship between the material world and its digital representations. Through documenting the various spatial patterns of Sandy-related tweeting both within the New York metropolitan region and across the United States, we make a series of broader conceptual and methodological interventions into the nascent geographic literature on big data. Rather than focus on how these massive databases are causing necessary and irreversible shifts in the ways that knowledge is produced, we instead find it more productive to ask how small subsets of big data, especially georeferenced social media information scraped from the internet, can reveal the geographies of a range of social processes and practices. Utilizing both qualitative and quantitative methods, we can uncover broad spatial patterns within this data, as well as understand how this data reflects the lived experiences of the people creating it. We also seek to fill a conceptual lacuna in studies of user-generated geographic information, which have often avoided any explicit theorizing of sociospatial relations, by employing Jessop et al.’s TPSN framework. Through these interventions, we demonstrate that any analysis of user-generated geographic information must take into account the existence of more complex spatialities than the relatively simple spatial ontology implied by latitude and longitude coordinates. 相似文献
16.
Wolfgang Schott is the pioneer in paleoceanography and has established this research field within marine geology. His papers from the first half of the twentieth century are all published in German; therefore, the most inspiring results are given here as original quotes in English, since they paved the ground for all scientific discussions on climate stratigraphy, past ocean currents, and glacial interglacial cycles. 相似文献
17.
This critical review debates the issues raised in Mark Whitehead’s 2009 book, “State, Science and the Skies: Governmentalities of the British atmosphere”. After a short introduction that positions the book, four commentators draw on their own work in political geography, the sociology of science, atmospheric science and cultural geography, respectively, to offer sympathetic critiques of the book and its arguments. The critical review concludes with a response by the author to the issues raised. 相似文献
18.
Early Cambrian small skeletal fossils (SSFs) are studied and revised from the Zhenba–Fangxian Block of the transitional zone between the Yangtze Block and the South Qinling Terrane. The study reveals a diverse fauna with 47 species of various biological affinities, including the new species Gapparodus gapparites sp. nov. The SSFs are assigned to the newly defined Cambroclavus fangxianensis– Rhombocorniculum cancellatum Assemblage Zone. Based on the investigated SSF fauna from Zhenba County, Southeast Shaanxi of China and published data, a palaeobiogeographic study is carried out for the Cambrian Stage 3 (equivalent to the Atdabanian–Botoman of Siberia). A hierarchical Pearson similarity cluster analysis of 295 species from 32 regions of the world indicates a distinct palaeobiogeographic pattern with seven faunal provinces. The result is mostly consistent with existing palaeogeographic reconstructions for the early Cambrian. However, it is also shown that the SSF assemblages of the Zhenba–Fangxian Block have low similarity with those of the Yangtze Block. Instead, they share high similarity with those from Armorica, Tarim and the Karatau–Naryn terranes (South Kazakhstan/North Kyrgyzstan). The Yangtze Block has a unique SSF assemblage dissimilar to most of other regions. The Terreneuvian–Cambrian Stage 3 sedimentary sequence of the Zhenba–Fangxian Block is more consistent with that of the South Qinling Terrane. Besides, sedimentary Ediacaran manganese ore deposits and Cambrian barite/witherite deposits have unique distribution pattern on the Zhenba–Fangxian Block. Derived from the profound dissimilarities in faunal composition, sedimentary sequence and distribution of sedimentary ore deposits, we hypothesize that during the Neoproterozoic–Cambrian transition, the Zhenba–Fangxian Block might have been an independent terrane and more distant from the Yangtze Block. The palaeobiogeographic analysis of SSFs also indicates a closer alliance between Avalonia and Siberia. It corroborates the palaeogeographic reconstruction of North China at the margin of Gondwana, in the vicinity of Australia, Antarctica, and Armorica. 相似文献
19.
Doklady Earth Sciences - The U–Pb and Lu–Hf isotope studies of detrital zircons from Mesozoic metasedimentary rocks of the Sorukan and Naldinda formations of the Ul’ban terrane... 相似文献
20.
An overview is presented of the actinopterygian fishes from the Late Jurassic (Late Kimmeridgian and Early Tithonian) ‘Plattenkalke’ near Solnhofen (Solnhofen lithographic limestone), Bavaria, Germany. The fish fauna is very diverse, with the palaeonisciform Coccolepis, halecostomes such as Lepidotes, Heterostrophus, three genera of macrosemiids and six genera of pycnodontiforms, halecomorphs including two genera of caturids, two genera of amiids, Ophiopsis, ‘Furo’, Ionoscopus, Brachyichthys, Callopterus, Liodesmus, ?Lophiurus, five genera of pachycormids, three genera of pholidophorids, Pleuropholis, two genera of aspidorhynchids and eleven genera of basal teleosts. Although several groups have been subject of revision, most of the fauna remains poorly known. Study of this rich fauna will provide a lot of information on the phylogeny and interrelationships of halecostome fishes. 相似文献
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