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1.
Augering to the east of Newport, Isle of Wight, has proved the presence of the ‘Variolarius Bed’ at the top of the Selsey Sand Formation. As well as its characteristic flood of the foraminifer Nummulites variolarius it contains a biostratigraphically useful ostracod assemblage, characterised by dominant Leguminocythereis haskinsi and subdominant Cytherella dixoni, with less numerous Cytheridea rigida, Oertliella aculeata, Cytheretta forticosta and Pterygocythereis cornuta.  相似文献   

2.
Three genera, known by dorsal finspine, are reported from conglomeratic sandstone at the base of the Lower Permian (Kungurian) Irati Formation (Paraná Basin) near Rio Claro, São Paulo State, Brazil, noteworthy for the great richness of vertebrate fossils. The fossils include: (1) the previously known Sphenacanthus with the species Sphenacanthus sanpauloensis and an indeterminate species; (2) the Permian – Carboniferous genus Amelacanthus; (3) a new indeterminate Chondrichthyes. These fossils are found together with: continental, fresh-water and salt-water vertebrates. The analysis of this assemblage allows inference about the origin of Paraná Basin Chondrichthyes as well as reconstruction of the paleoenvironment and the possible geographic isolation of these fishes during the Permian in Brazil.  相似文献   

3.
Anoop Nayak 《Geoforum》2003,34(3):303-315
This article seeks to bring young respondents more sharply into focus by considering fear of crime ‘through children’s eyes’. By incorporating children’s perspectives it is argued that more inclusive and integrative community safety initiatives may arise. Inspired by the recent flowering of research undertaken in childhood studies by social and cultural geographers, the study seeks to make a theoretical, empirical and spatial contribution to debates in the field. Based on the findings of a large-scale school survey, the responses indicate that children have an acute place-based sensitivity to a range of highly relevant community safety issues. This includes detailed reflections concerning the place of policing, boredom, youth gangs, motorcars and drugs in their neighbourhoods. It is suggested that the inclusion of children’s accounts into geographical debates not only enriches our knowledge of childhood studies, but also adds detail and texture to our understandings of fear of crime.  相似文献   

4.
Chih Yuan Woon 《Geoforum》2011,42(3):285-296
Geographers’ interest in the productive intersections between fear and issues of (counter)terrorism has flourished in recent years. These studies have been important in their critical analyses of geopolitical relations by exposing how fear has been driving unjust policies and violent initiatives. However, I suggest that these lines of inquiries often neglect the localized playing out of fears, particularly how such sentiments can potentially stimulate actions and affect the practices and progress of politics at different geographical scales.This paper addresses the aforementioned lacuna by scrutinizing how fear is bounded up with the geographical extension of the US-led ‘war on terror’ to the Philippines in the post 9/11 era. I argue that the framings of terrorism in the country have allowed the government to manipulate fear to justify destructive strategies for the eradication of imminent ‘threats’. However such initiatives are not only counterproductive to rooting out the sources of terror but also aid in the (re)production of violence. Not assuming the inevitability of such elegaic outcomes, I showcase the efforts of the Philippines communist ‘rebel’ group, Rebulusyonaryong Partido ng Manggagawa ng Mindanao (RPM-M), in repudiating official terrorism discourse by emphasising instead issues of state-induced vulnerability and marginalization. This in turn allows fear to be transformed into other modalities of emotions that are central to the formation of coalitional resistances to the arbitrary effects of state violence and its vicissitudes.By illuminating the constitution of (non)violence through emotions, there is an inherent wish to disrupt the natural conjoining of fear, terror and violence dominating contemporary geopolitical imaginations. Crucially, the implications of emotions for the thinking and doing of nonviolence augments a concrete pathway for operationalising a radical praxis of peace and justice that explicitly eschews a resort to force.  相似文献   

5.
A one-day Geologists’ Association field excursion to the Bawdsey Peninsula in coastal Suffolk is described, with a guided tour of ‘The Pliocene Island’ at Sutton Knoll and visits to examine coastal erosion, the London Clay and Red Crag at Bawdsey East Lane, and the Red Crag at Alderton and Ramsholt. The depositional environments indicated by the Crag sediments and faunas are discussed, and non-derived Red Crag mollusc faunas at Sutton and sand-wave mollusc assemblages from Ramsholt are described.  相似文献   

6.
This paper investigates the ways in which national and regional policies relate to farming activities and concerns amongst the rural population in an area of southern Africa. The struggle to make a living through farming was a common theme to emerge from research about changing livelihoods in response to both variability in the environment and changes in policy. This local discourse echoed regional debates about land and agrarian reform in post-apartheid South Africa and the uncertain future of mixed farming in Botswana. It also raised broader questions about the viability of the future of small-medium-scale farming systems in rural areas in Africa, especially those within dynamic dryland environments such as the Kalahari. This paper looks specifically at the links between poverty and asset holding and aims to identify the ways in which people are or are not able to utilise or mobilise these assets in times of need. We argue that this can vary significantly between seemingly similar settlements, and similar households and that understanding this complexity is the key to recognising how future interventions many impact upon people’s lives. Too often, in the quest to produce understandings of poverty and livelihoods, the complexity, incongruity and reality of day-to-day practices are overlooked. Thus we seek to draw out the interactions between policy and natural resource use, and the capital asset changes involved in these interactions, which influence the sustainability of livelihoods and the differing levels of poverty and vulnerability.  相似文献   

7.
Paula Meth 《Geoforum》2003,34(3):317-327
An examination of domestic violence and where it takes place provides significant insight into debates about the meaning of home. It is argued here that discussions of domestic violence could make more use of feminist geographers’ and development theorists’ analyses of the home. Examining the experiences of homeless and insecurely housed women in Durban, the paper aims to explore ideas of ‘home’ implicit in much research on domestic violence and argues that these ideas require further examination. The paper focuses on three assumptions about the home (in experiences of domestic violence); namely, the home as a formal material space, the home as private, and the domicile as home. In conclusion the paper argues for a more nuanced understanding of home.  相似文献   

8.
This paper aims to refine earlier research on the geographies of Islamic financial services (IFS) through a study of how cities are being connected through interlocking directorates in Shari’a advisory boards of IFS firms. The relevance of this analysis is discussed against the backdrop of recent critiques of mainstream ‘world cities’ research because of structuralist and universalizing tendencies. By applying a network concept to the relationalities of world cities within financial circuits, we explore the nested city/firm/actor structure behind Shari’a board membership, and reassess the connectivity of cities in the IFS network in terms of the role and spatialities of interlocking Shari’a boards. The results show that Gulf cities, most notably Manama, Dubai and Kuwait City are particularly well-connected, while also mainstay financial centres outside the Middle East, such as London and New York are networked by interlocking board memberships of a global Shari’a elite. The dominant position of Manama is traced back to its role as a standard-setting city for Shari’a-compliant investments, which materializes through the enacted presence of an array of highly interlocked regulatory bodies and mediating elites.  相似文献   

9.
10.
Lindsey Carte  Erin Daley 《Geoforum》2010,41(5):700-710
In response to a growing body of literature encouraging geographers to present textured, regional case studies that demonstrate how neoliberalism functions at diverse scales, this article presents a nuanced account of neoliberalism in Mexico’s Yucatan peninsula. The study seeks to illustrate how neoliberal reforms to agriculture and ongoing neoliberal tourism development in the Yucatecan state of Quintana Roo intersect to create a unique regional context for migration between the state’s rural areas and Mexico’s largest planned tourism development zone in Cancun. The research presented is based on a series of in-depth qualitative interviews that took place in 2003 with rural residents and regional migrants working in Cancun. Through the employment of an experiential definition of neoliberalism, grounded in the lived experiences and perceptions of study participants, the article suggests that rural-urban tourist pole migration is the result of a complex negotiation of the region’s neoliberal landscape. The article argues that rural residents’ and migrants’ perceptions of the failure of agriculture as a livelihood is shaped relative to the perceived success of the tourism industry and better livelihood opportunities in Cancun. These widespread perceptions of agricultural failure in the Yucatan peninsula are constructed not solely in response to local conditions but rather in response to the overall regional outcome of neoliberal economic restructuring initiatives which have negatively affected traditional agriculture in the rural sphere while privileging tourism development in the urban sphere centered in Cancun.  相似文献   

11.
Abstract The Pennine rocks exposed in the south-east Tauern Window, Austria, contain mineral assemblages which crystallized in the mid-Tertiary ‘late Alpine’regional metamorphism. The pressure and temperature conditions at the thermal peak of this event have been estimated for rocks at four different structural levels using a variety of published and thermochemically derived geobarometers and geothermometers. The results are: (a) In the garnet+chlorite zone, 2–5 km structurally above the staurolite+biotite isograd: T= 490.50°C, P= 7° 1 kbar; (b) Within 0.5 km of the staurolite+biotite isograd: T= 560±300C, P=7.1 kbar; (c) In the staurolite+biotite zone, c. 2.5 km structurally below the staurolite+biotite isograd: T= 610±30°C, P=7.6±1.2 kbar; (d) In the staurolite+biotite zone, 3–4 km structurally below the staurolite+biotite isograd: T= 630±40°C, P= 6.6±1.2 kbar. The pressure estimates imply that the total thickness of overburden above the basement-cover interface in the mid-Tertiary was c. 26.4 km. This overburden can only be accounted for by the Austro-Alpine units currently exposed in the vicinity of the Tauern Window, if the Altkristallin (the ‘Middle Austro-Alpine’nappe) was itself buried beneath an ‘Upper Austro-Alpine’nappe or nappe-pile which was 7.4 km thick at that time. The occurrence of epidote + margarite + quartz pseudomorphs after lawsonite in garnet, indicates that part of the Mesozoic Pennine cover sequence in the south-east Tauern experienced blueschist-facies conditions (T<450°C, P<12 kbar) in early Alpine times. Evidence from the central Tauern is used to argue that the blueschist-facies imprint post-dated the main phase of tectonic thickening (D1A) and was thus a direct consequence of continental collision. Combined oxygen-isotope and fluid-inclusion studies on late-stage veins, thought to have been at lithostatic pressure and in thermal equilibrium with their host rocks during formation, suggest that they crystallized from aqueous fluids at 1.1±0.4 kbar and 420.20°C. Early Alpine, late Alpine and vein-formation P–T constraints have been used to construct a P–T path for the base of the Mesozoic cover sequence in the south-east Tauern Window. The prograde part of the P–T path, between early and late Alpine metamorphic imprints, is unlikely to have been a smooth curve and may well have had a low dP/dT overall; the decompression (presumably due to erosion) which occurred immediately before the thermal peak and possibly also earlier in the Tertiary, was probably partly or completely cancelled by the effects of early- to mid-Tertiary (D2A) tectonic thickening. The thermal peak of metamorphism was followed by a phase of almost isothermal decompression, which implies a period of rapid uplift in the middle Tertiary. The peak metamorphic P–T estimates are compared with the solutions of England's (1978) one-dimensional conductive thermal model of the Eastern Alps, and are shown to be consistent with the idea that the late Alpine metamorphism was caused by tectonic burial of the Pennine Zone beneath the Austro-Alpine nappes in the absence of extraneous heat sources, such as large intrusions, at depth.  相似文献   

12.
Presented here are stable nitrogen isotope data from a rock hyrax (Procavia capensis) middens from northwestern Namibia that record a series of rapid aridification events beginning at ca. 3800 cal yr BP, and which mark a progressive decrease in regional humidity across the Holocene. Strong correlations exist between this record and other terrestrial and marine archives from southern Africa, indicating that the observed pattern of climate change is regionally coherent. Combined, these data indicate hemispheric synchrony in tropical African climate change during the Holocene, with similar trends characterising the termination of the ‘African Humid Period’ (AHP) in both the northern and southern tropics. These findings run counter to the widely accepted model of direct low-latitude insolation forcing, which requires an anti-phase relationship to exist between the hemispheres. The combined dataset highlights: 1) the importance of forcing mechanisms influencing the high northern latitudes in effecting low-latitude climate change in Africa, and 2) the potential importance of solar forcing and variations in the Earth's geomagnetic shield in determining both long-term and rapid centennial-scale climate changes, identifying a possible mechanism for the variations marking the AHP termination in both the southern and northern tropics.  相似文献   

13.
陈安泽 《地球学报》2016,37(5):535-561
笔者从中国地质科学院建立之始,就随着地质部陈列馆(即现中国地质博物馆)划归中国地质科学院领导,而成为其创始研究人员,60年来从没离开过,因此见证了其全部历史。在中国地质科学院工作过程中,以笔者为主,利用中国地质科学院的学科优势和挂靠单位中国地质学会学术团体这个全国性学术交流平台的有利条件,将地球科学运用到为中国旅游业发展服务中去,从而创立了一门地学与旅游相结合的新学科——旅游地学(Tourism Earth-science);在旅游地学理论指导下,提出了建立地质公园的建议和一整套实施方案,经过艰辛努力,终于促使地质公园得以建立;地质遗迹是建立地质公园和发展旅游业的重要地质资源,是旅游地学的主要研究对象。旅游地学与地质公园都是中国地质工作者的首创,是中国地质科学院的重大科学研究成果之一,其在中国地质工作发展史上具有里程碑意义。本文将旅游地学和地质公园产生的历史背景、研究内容、发展过程、建设现状与国内外发展趋势,以及地质遗迹资源的类型划分、评价准则、形成与分布规律、应用保护现状综述如下,以作为献给中国地质科学院建院60周年的礼物。  相似文献   

14.
This paper examines primary school children’s experiences of travelling between home and school within three neighbourhoods. Our investigation is set in Auckland, New Zealand, where parental practices such as chauffeuring are commonplace, yet are increasingly recognised as limiting children’s physical fitness and environmental awareness. Drawing on children’s voices, writing and photographs, we investigate how children currently travel to school, how they would like to travel, and how their perspectives on neighbourhood space vary by age, socio-economic status and school location. Findings reveal that over half of the participants did not like the way they travelled to school. Most desire to travel independently within public space, but are limited in their ability to do so, given the fears and obstacles that prevail within their neighbourhoods. We contend that restricted use of public space diminishes children’s agency in inner suburbs. Our analysis reveals that children favour ‘active travel’ for many of the same reasons as health professionals and transport planners. We conclude that as long as children are seen as innocents in need of protection, they will have limited agency in travel decisions and highly contingent access to public space.  相似文献   

15.
The Teplá Crystalline unit (TCU), western Bohemian Massif, proves highly suitable for studying the effects of differential metamorphic reworking on the U–Th–Pb systematics in monazite, as the overprint of Variscan regional metamorphism onto high-grade Cadomian paragneisses intensifies progressively towards the northwest. Although variably hampered by scarcity, small size, and low uranium contents of monazite, isotope dilution–thermal ionisation mass spectrometry of monazite from paragneisses from the garnet, staurolite, and kyanite zones of the TCU gives a narrow 206Pb/238U age range from 387 to 382 Ma for Variscan peak metamorphism. These data are supported by 382–373 Ma monazite ages derived from electron microprobe analyses. Inheritance of older components in grains from the central TCU imply major “resetting” of pre-Variscan monazite around 380 Ma, possibly due to widespread garnet growth during Variscan metamorphism, which led to the consumption of pre-Variscan high-Y monazite and subsequent growth of new low-Y monazite. Concordant 498–494 Ma monazite ages in a migmatitic paragneiss close to the adjacent Mariánské Lázně Complex (MLC) grew in response to metagabbro emplacement in the MLC from 503 to 496 Ma and not during either Cadomian or Variscan regional metamorphism. Backscatter imaging and electron microprobe analyses reveal that discordant monazite of the migmatite comprises a mix of various age domains that range from ca. 540 to 380 Ma. Combined evidence presented here suggests that instead of Pb loss by volume diffusion, the apparent resetting of the U–Th–Pb systematics in monazite rather involves new crystal growth or regrowth by recrystallisation and dissolution/reprecipitation.  相似文献   

16.
In order to examine the transportation and deposition mechanisms of Hg, we investigated the ore and hydrothermal alteration minerals and solid organic matters from Itomuka mercury mine located in the eastern part of central Hokkaido. In addition to the ore minerals, native mercury and cinnabar, quartz, marcasite, alunite, kaolinite, and minor amounts of pyrite and smectite were identified in the Hg ore by powder X‐ray diffraction (XRD) analysis. This mineral assemblage of acid sulfate alteration was likely developed under the conditions of low temperature (≤100°C) and low pH (≤2) in the steam‐heated environment. The H2SO4 was produced above the water table by the oxidation of H2S separated from deep, near‐neutral fluids by boiling. The dominance of native mercury over cinnabar in Hg ore indicates that the greater part of mineralized Hg was transported as Hg0 in aqueous solution and vapor with low sulfur fugacity. The solid organic matters found in the Hg ore were analyzed with SEM‐EDS, micro‐XRD, and micro‐Fourier transform infrared (FTIR) spectroscopy, and these results suggest that the organic matters contributed to keeping the low fO2 of the Hg‐bearing fluid and transportation of Hg as Hg0 in S‐poor condition. Because the solubility of Hg in acidic fluid is low, neutral to alkaline fluid seems to have leached Hg from the basement sedimentary rocks of Hidaka Group which also supplied the organic matters to the fluid. The oxidation and cooling of Hg‐bearing solution and vapor triggered the deposition of liquid Hg as a primary phase.  相似文献   

17.
The Jalama batholith (Spain and Portugal) is one of the numerous granites of the Central Iberian Zone with Sn- and W-associated mineralisation. On the basis of petrographical and geochemical characterisation three types of granite have been distinguished: inhomogeneous granitoids, porphyrytic granites and leucogranites, all of these being peraluminous and subalkaline. All the granites correspond to S-type granites. The field data, the petrography and lack of geochemical affinity relationships of the leucogranites with the remaining granites indicate that their geneses correspond to an independent magma batch and superimposed fractional crystallisation process. The granitic units show subparallel REE patterns. There is a decrease in total REE and an increase in the negative Eu anomaly from the inhomogeneous granitoids to leucogranites. Some leucogranites show relatively low contents of Sn and W almost certainly due to segregation in the magma of a melt rich in water carrying Sn-W. These elements are concentrated in the water phase, which eventually gives rise to Sn-W-associated mineralisation.The ages obtained by means of a whole-rock Rb-Sr isochron for the granites mainly indicate an early intrusion of the inhomogeneous granitoids (319±10 Ma), followed in time by porphyrytic granites (279±9 Ma), which can be associated to the late-post-kinematic granites within the third Variscan deformation phase (D3).Apart from the average Sn content, the variations of trace elements, principally Sr, Ba, Rb, Th and P, establish that the porphyritic granites and the inhomogeneous granitoids will be barren granites while the leucogranites and the subfacies at the margin of the porphyritic granites correspond to granites with mineralisation potential. It is precisely in these granites of the Jálama batholith that the Sn-W mineralisation is located, for which the criteria utilised has been demonstrated to be effective.  相似文献   

18.
Alpine metamorphism, related to the development of a metamorphic core complex during Cretaceous orogenic events, has been recognized in the Veporic unit, Western Carpathians (Slovakia). Three metamorphic zones have been distinguished in the metapelites: 1, chloritoid + chlorite + garnet; 2, garnet + staurolite + chlorite; 3, staurolite + biotite + kyanite. The isograds separating the metamorphic zones have been modelled by discontinuous reactions in the system K2O–FeO–MgO–Al2O3–SiO2–H2O (KFMASH). The isograds are roughly parallel to the north‐east‐dipping foliation related to extensional updoming along low‐angle normal faults. Thermobarometric data document increasing PT conditions from c. 500 °C and 7–8 kbar to c. 620 °C and 9–10 kbar, reflecting a coherent metamorphic field gradient from greenschist to middle amphibolite facies. 40Ar/39Ar data obtained by high spatial resolution in situ ultraviolet (UV) laser ablation of white micas from the rock slabs constrain the timing of cooling and exhumation in the Late Cretaceous. Mean dates are between 77 and 72 Ma; however, individual white mica grains record a range of apparent 40Ar/39Ar ages indicating that cooling below the blocking temperature for argon diffusion was not instantaneous. The reconstructed metamorphic PTt path is ‘clockwise’, reflecting post‐burial decompression and cooling during a single Alpine orogenic cycle. The presented data suggest that the Veporic unit evolved as a metamorphic core complex during the Cretaceous growth of the Western Carpathian orogenic wedge. Metamorphism was related to collisional crustal shortening and stacking, following closure of the Meliata Ocean. Exhumation was accomplished by synorogenic (orogen‐parallel) extension and unroofing in an overall compressive regime.  相似文献   

19.
Hillary Jenks 《GeoJournal》2008,73(3):231-244
The “Little Tokyo” neighborhood of Los Angeles was the center of pre-internment community life for Japanese immigrants and their children and is still considered the symbolic home of later generations of Japanese Americans in Southern California. Drawing on three years of ethnographic research in Little Tokyo, I explore in this article how contemporary Japanese Americans have used and transformed this ancestral landscape in order to express, contest, and formalize collective memories of the Japanese American experience, particularly with regard to their place in the national body politic. Historical narratives inscribed at many places in Little Tokyo, both informal and institutional, project a narrative of sacrifice, suffering, and redemption in the context of internment and military service, articulating neatly with mainstream American tropes of overcoming hardship as a process of ‘earning’ citizenship and its benefits. However, such narratives are also contested by alternative interpretations and representations of these spaces that describe a special role for Japanese Americans in making demands of their government, rather than just sacrifices to it. The resulting debates, disagreements, and even occasional consensus around constructions of nation, identity, community, and belonging are rooted in the ‘sacred ground’ of Little Tokyo, gathering meaning and persuasive power through their connection to a symbolically dense site of shared memory. The multiple memory projects of this landscape reveal how Japanese Americans have envisioned their relationship to the concept of America, to each other, and to other communities with shared experiences in a diverse metropolis.
Hillary JenksEmail:
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20.
Sedimentary successions of non‐marine basins can be considered in terms of accommodation space and sedimentary supply changes. Changes in accommodation space controlling the large‐scale architecture of non‐marine basins are different in areas with high and low sedimentary supplies. Uplift of intrabasinal monoclines and anticlines reduced the available accommodation space, resulting in changes in both the geometry of the depositional sequences and the large‐scale architecture of fluvial, mudflat and shallow carbonate lacustrine deposits. Main drainage fluvial systems record areas with a high sedimentary supply, while mudflats and shallow fluctuating lakes represent areas that received less sediment. Two end members in the large‐scale architecture of main drainage fluvial system in the Almazán Basin (Spain) are: (i) ribbon‐shaped channel fills with low interconnectivity which pass laterally into mudflats dominated by mudstones and evaporites and into palustrine and shallow carbonate lacustrine deposits (mainly in the A2 depositional sequence); and (ii) sheet‐like channel fills with high interconnectivity laterally correlated with stacked calcretes in the marginal mudflats (in the upper part of A3). Ribbon‐shaped channel fills formed in areas of high accommodation space and sheet‐like channel fills formed in areas of reduced accommodation space.  相似文献   

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