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This article explores the role of geographical context in generating a stigmatised identity among residents of Tara rural subdivisions in the coal seam gas fields in Queensland’s Western Downs. The research was based on qualitative interviews with Tara ‘Blockies’, as these residents are commonly referred to, that revealed how their existence in the middle of an agrarian region resulted in the assignation of a stigma that has marked them as different, and subsequently devalued their status. We explain that this distinction and category division of the normals, referring to Tara’s Agrarian residents, from the ‘stigmatised’ led to an antagonistic relationship that prevented successful socio-cultural assimilation. We demonstrate how an immoral place becomes disadvantaged, resulting in poor well-being, and how imposed labels threaten the self-esteem of its occupants.  相似文献   

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Outbursts of coal and gas are closely related to coal microstructures. Part of microstructures of coal areassociated with the coal-forming environments, but most of them are produced by tectonic deformation. In thispaper the types of microstructures of coal are distinguished according to the types and features of tectonicdeformations, which is convenient and can be easily employed by geologists. Based on the SEM study on coalpetrography of No.4 and No.6 coal seams of the Yutianbao coal mine, Nantong coal field, five types of coalare distinguished: nontectonic coal, microfissure coal, microcleavage coal, cataclastic coal and mylonitic coal.The microstructural features of various types are described in detail and their geological implications and rela-tionships with coal and gas outbursts are also discussed. Special mention is made of a series of the features ofplastic deformation of mylonitic coal. It is concluded that, other things being equal, the place with myloniticcoal is the most likely risk site for outbusts.The process and mechanism of coal and gas outbursts are suggested based on a series of changes inmicrostructures of the coal after bursting. In the process of gas outbursts, the plastic deformation issuperimposed by brittle deformation, thus ejecting large quantities of coal dust.  相似文献   

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The mineralogy and geochemistry data are presented for thirty-seven shales,four concretions,two carbonate sediments and seven lignites from the Marathousa coal field of the Megalopolis Basin in Greece.The argillaceous rocks consist of chlorite,illite,kaolinte,albite,quartz.opal-A,calcite and dolomite;the concretions of aragonite,gypsum and pyrite;and the carbonate rocks of calcite,quartz and illite.The mineral matter in the lignites consists of gypsum,quartz,albite,chlorite,illite,opal-A,dolomite,pyrite,and rarely calcite and kaolinite Athree-factor model explains the total variaition of major and trace elements in the argillaceous sediments.The first factor is an aluminosilicate factor and involves the following elements:Al,Si,Mg,Na,K,Ti,Mn,Nb,Y,Rb,Zn,Cu,Ni,Cr,Nband V,associated with chlorite,albite and illite.The second factor involves the elements Ca,Sr,Ba,Znand Sc and is related to carbonate lithology and mainly the carbonate concretions with gypsum.The third factor involves Fe and Ce with a weak association with Mn.The diagenesis of the Marathousa sediments and lignites was not very advanced as indicated by (a) the total thickness of the sequence (500m),(b) the presence of biogenic silica(opal-A) and (c) the age of the deposit(Pleistocene).FOr these reasons the rpresence of chlorite,illite and kaolinite in the sediments and lignite is due not to diagenetic reactions but to weathering of the flysch and metamorphic rocks at the edges of the Megalopolis Basin and transport of the weathering products(illite,chlorite,kaolinite)into the basin of deposition.The diagenetic minerals of the Marathousa sequence include pyrite,gypsum,dolomite and aragonite.  相似文献   

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Nepea narinosa Whitehouse, 1939, is as yet the only known species of the Nepeidae and Nepeacea. It is based on fragmentary material unsuitable for conclusive interpretation. The census of Nepeidae as yet unpublished includes five genera and twelve species, confined to the Middle and early Upper Cambrian of Australia. All nepeids have cedariform posterior sutures, free cheeks fused into a unit, a preglabellar boss, forked ocular ridges and a pustulose test. Nepea narinosa is distinguished by its very long intergenal spines and pointed, falcate palpebral lobes provided with a doublure.  相似文献   

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Quartz‐andalusite‐fuchsite rocks in an Archaean greenstone belt at Menzies, Western Australia, are described in their geological setting. They are shown to have developed from intense metasomatism of layered rocks of komatiitic composition. Ratios of the immobile components Al2O3, TiO2, Cr, V and Zr are consistent, despite wide variations in their absolute values, and compare closely with those of an underlying komatiite suite. Marked depletion of Ca, Na, Mg and Fe has led to a strongly peraluminous composition and enhanced Cr values. Silicification and introduction of K has also occurred. Most of the metasomatism took place before peak metamorphism, and the mineral assemblage is now dominated by andalusite, fuchsite, and recrystallized quartz. Schlieren or vein‐like segregations rich in andalusite, chromite, rutile and minor sulphides and tourmaline are interpreted as the original fluid pathways, where concentration of immobiles was achieved through solution of mobile components, and volume loss. They have been termed residual veins. Metasomatism is believed to have taken place by synvolcanic processes analogous to those operating in modern hot spring systems. The rocks were severely modified by metamorphism and tectonism. The fuchsitic rocks at Menzies are compared to similar rocks in other areas.  相似文献   

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The Production and Release of CFCs from Coal Combustion   总被引:3,自引:0,他引:3  
The destruction of the ozone layer in the atmosphere caused by industrially synthesized CFCs has aroused greatest concerns from the international society, but the CFCs formed from burning of coal containing fluorine have not been recognized by the world yet. In the present study, we condensed the gas through cold traps and used the GC-MS to measure the gas composition, and found that the content of CFC-12 in the smog from coal combustion was significantly higher than the background value of the local atmosphere. This proves that CFC-12 is formed in the process of coal combustion. This paper discusses a new source of non-synthesized CFCs.  相似文献   

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《Gondwana Research》2013,24(4):1656-1658
The abundant and diverse assemblage of filamentous microbial fossils permineralized in the ~ 3465 Ma Apex chert of northwestern Australia — among the oldest records of life — are arguably the “best studied,” by the most workers using the most advanced techniques, in the history of science. Despite the extensive body of data establishing the biogenicity of the demonstrably cellular carbonaceous Apex fossils, Pinti et al. (2013) and Marshall and Marshall (2013) have raised issues regarding the interpretation of their studies of the Apex chert presented in our recent review article (Schopf and Kudryavtsev, 2012). We agree with the assessment of both of the relevant papers by Pinti et al. (2009, 2013): the observations they report do not apply to the bona fide microscopic fossils of the Apex chert. Similarly, like the minute objects reported by Pinti et al. (2009, 2013), the “quartz and haematite-filled fractures” discussed by Marshall and Marshall (2013) are mineralic pseudofossils that are not relevant to interpretation of the Apex fossil microbes and their suggestion that “multiple populations of carbonaceous material may be a wide-spread issue through out the Precambrian” is without merit.  相似文献   

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Cambrian marine, grey shales are widespread, and so are Cambrian intertidal, redbeds with weakly developed marine-influenced paleosols. A broader view of Cambrian landscapes and soilscapes now comes from paleosols of alluvial coastal plains of the Cambrian (to Ordovician?) Parachilna, Billy Creek, Moodlatana, Balcoracana, Pantapinna and Grindstone Range Formations in the central Flinders Ranges of South Australia. Paleosols are recognised by soil structures such as calcareous nodules (caliche) and cracked ridges (mukkara). They also show gradational changes down-profile in minerals, grainsize and chemical composition comparable with soils. Some of these Cambrian paleosols are thick (>1 m) and well developed (large caliche nodules). They indicate stable alluvial and coastal landscapes of quartzo-feldspathic and locally tuffaceous sediments. Paleoclimates were generally semiarid, although several intervals of subhumid paleoclimate coincide with local marine transgression. Drab-haloed filaments in red claystones, and elephant-skin and carpet textures in sandstones of some of the paleosols may be evidence of biological soil crusts, and some waterlogged marginal marine and lacustrine paleosols had animal burrows. Cambrian paleosols of the Flinders Ranges are assignable to the modern soil orders Vertisol, Aridisol, Inceptisol and Entisol. Modern soils of the Flinders Ranges and central Australia are within the same orders as the Cambrian paleosols, supporting evidence from paleogeomorphology that some Australian landscapes and soilscapes are very ancient indeed.  相似文献   

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Many salt lakes have formed in southern Australia where regional saline groundwaters form discharge zones. Some of these groundwaters are characterized by acidity and high salinity. These are commonly found where underlying Tertiary sediments are sulfide-…  相似文献   

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A largely convergent setting is proposed for crustal, tectonic and basin evolution of the intracratonic regions of north‐central Australia between 1800 and 1575 Ma. The new geodynamic model contrasts with previous proposals of widespread extension during the Leichhardt, Calvert and Isa intervals. Local transtensional to extensional structures exist, but these are best explained by a combination of flexural, thermal and dynamic processes related to an active southern margin. The development of thick accumulations of sediments (superbasins) is linked geodynamically to interpreted active margin processes (subduction and magmatic arcs) in central Australia. A synthesis of geochemical data from the 1870–1575 Ma igneous units from the Arnhem, McArthur and Mt Isa regions of north‐central Australia confirms the intracratonic setting of these units and suggests that a long‐lived thermal anomaly was responsible for the generation of both mafic and felsic magmas. The geochemical characteristics suggest the igneous units are derived from the lithospheric mantle and are not typical rift‐ or plume‐related melts. A review of the U–Pb SHRIMP ages for the entire region demonstrates the minimum distribution of correlative igneous rocks was widespread. Exotic populations in the 207Pb/206Pb isotopic data provide insights into the nature and evolution of the crust throughout north‐central Australia. Archaean inheritance is found to be nearly ubiquitous. The data support the temporal subdivision of north‐central Australia into the Leichhardt (1800–1750 Ma), Calvert (1750–1690 Ma) and Isa (1690–1575 Ma) intervals which are marked by superbasins and concomitant episodes of igneous activity. A highly heterogeneous pre‐superbasin crust is interpreted from regional, newly processed geophysical data. The cratonic portion of north‐central Australia is interpreted to consist of three broad northwest‐trending belts or elements that are further distinguished into western, central and eastern geophysically distinct provinces. A map of the superbasin distribution is derived and integrated with structural and stratigraphic data to assess the evolution of the basins and the crust through time. The superbasin successions of north‐central Australia are synchronous and widespread, although not necessarily interconnected. The tectonic model incorporates dynamic tilting of the craton during episodes of subduction and transmission of compressive intraplate stresses through the craton during intervening episodes of orogeny. These processes resulted in flexure, strike‐slip deformation and a complex thermal structure. These mechanisms account for the subsidence and basin evolution that results in widespread ramp and strike‐slip basins. The model also accounts for the thermal history recorded by magmatic events. The proposed geodynamical model provides a unifying crustal evolution scenario for central and northern Australia for approximately 225 million years of the Proterozoic.  相似文献   

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