The influence of palaeoenvironment and lava flux on the emplacement of submarine, near-shore Late Permian basalt lavas, Sydney Basin (Australia)

Lava flux and a low palaeoslope were the critical factors in determining the development of different facies in the Late Permian Blow Hole flow, which comprises a series of shoshonitic basalt lavas and associated volcaniclastic detritus in the southern Sydney Basin of eastern Australia. The unit consists of a lower lobe and sheet facies, a middle tube and breccia facies, and an upper columnar-jointed facies. Close similarities in petrography and geochemistry between the basalt lavas from the three facies suggest similar viscosities at similar temperatures. Sedimentological and palaeontological evidence from the sedimentary units immediately below the Blow Hole flow suggests that the lower part of the volcanic unit was emplaced in a cold water, shallow submarine environment, but at least the top of the uppermost lava was subaerial with some palaeosol development. The lower lobe and sheet facies was emplaced on a low slope (<2°) in a lower to middle shoreface environment with water depths of 20–25 m. Lava may have transgressed from subaerial to subaqueous and was emplaced relatively passively with lava flux sufficiently high and uniform to form lobes and sheets rather than pillows. The middle unit probably originated from a subaerial vent and flowed into a shallow (10–15 m) submarine environment, and wave action probably interacted with the advancing lava front to form a lava delta. Lava flux was sufficiently high to produce well-developed, subcircular lava tubes, which lack evidence for thermal erosion. In some areas, lava ‘burrowed’ into the unconsolidated, water-saturated lava delta and sand pile to produce intrusive contacts. The upper columnar-jointed unit represents a ponded facies probably emplaced initially in water depths <5 m but whose top was subaerial.     

Methane and CO2 sorption and desorption measurements on dry Argonne premium coals: pure components and mixtures

Sorption and desorption behaviour of methane, carbon dioxide, and mixtures of the two gases has been studied on a set of well-characterised coals from the Argonne Premium Coal Programme. The coal samples cover a maturity range from 0.25% to 1.68% vitrinite reflectance. The maceral compositions were dominated by vitrinite (85% to 91%). Inertinite contents ranged from 8% to 11% and liptinite contents around 1% with one exception (Illinois coal, 5%). All sorption experiments were performed on powdered (−100 mesh), dry coal samples.Single component sorption/desorption measurements were carried out at 22 °C up to final pressures around 51 bar (5.1 MPa) for CO₂ (subcritical state) and 110 bar (11 MPa) for methane.The ratios of the final sorption capacities for pure CO₂ and methane (in molar units) on the five coal samples vary between 1.15 and 3.16. The lowest ratio (1.15) was found for the North Dakota Beulah-Zap lignite (VR_r=0.25%) and the highest ratios (2.7 and 3.16) were encountered for the low-rank coals (VR_r 0.32% and 0.48%) while the ratio decreases to 1.6–1.7 for the highest rank coals in this series.Desorption isotherms for CH₄ and CO₂ were measured immediately after the corresponding sorption isotherms. They generally lie above the sorption isotherms. The degree of hysteresis, i.e. deviation of sorption and desorption isotherms, varies and shows no dependence on coal rank.Adsorption tests with CH₄/CO₂ mixtures were conducted to study the degree of preferential sorption of these two gases on coals of different rank. These experiments were performed on dry coals at 45 °C and pressures up to 180 bar (18 MPa). For the highest rank samples of this sequence preferential sorption behaviour was “as expected”, i.e. preferential adsorption of CO₂ and preferential desorption of CH₄ were observed. For the low rank samples, however, preferential adsorption of CH₄ was found in the low pressure range and preferential desorption of CO₂ over the entire pressure range.Follow-up tests for single gas CO₂ sorption measurements consistently showed a significant increase in sorption capacity for re-runs on the same sample. This phenomenon could be due to extraction of volatile coal components by CO₂ in the first experiment. Reproducibility tests with methane and CO₂ using fresh sample material in each experiment did not show this effect.     

A geography of natural perils

Earthquakes, tropical cyclones and floods are the most important natural perils in terms of human deaths on a global basis. In Australia, at least 4300 deaths in the last 200 years have been produced by heatwaves; about 2000–2200 each by tropical cyclones and floods; and bushfires and lightning strikes have each killed at least 650 people. On a global basis it appears that floods, tropical storms, droughts and earthquakes are the most damaging natural perils. In Australia, in terms of median damage per event, hailstorms are the most expensive insured natural peril, while three events—the 1989 Newcastle earthquake, 1974's Cyclone Tracy, and the 1990 Sydney hailstorm—produced 36 per cent of the total insured damage in the period since 1967. The Newcastle earthquake and the Sydney hailstorm have provided opportunities for new understandings of these perils and their consequences. While much has been learnt from the devastation of Rabaul town by the 1994 eruption, a rare opportunity for a detailed study of building damage has been lost. Without detailed studies, risk rating, where Risk = Hazard (or peril) × Vulnerability, is difficult.     

815℃灰化前后淮北煤中矿物质变化特征

以淮北煤田二叠纪5、4煤层15个煤样品为研究对象,对样品在815℃下进行灰化,并采用等离子体原子发射光谱(ICP-AES)对煤灰中成分进行测定,采用X射线衍射(XRD)对原煤以及灰化后的样品中矿物质成分进行了分析.在此基础上,探讨了煤中矿物质种类及影响煤中矿物质的主要因素,分析了煤中矿物质在815℃灰化前后的变化特征.结果表明,煤中矿物质种类受多种因素影响,灰化过程中矿物质的种类、含量会发生改变,且部分矿物在高温作用下发生变化,重新组合,形成相对较稳定的新矿物,从而为今后煤灰的综合利用提供科学论据.     

Seeds for Change? Attaining the benefits of community gardens through council policies in Sydney,Australia

Modern industrial systems of food production cause a wide range of detrimental impacts to the environment, human health and society. Integrating community gardens into local food systems is one way to counteract some of those impacts. This research looks at the elements that community garden policies should contain in order to best promote community gardens and attain their benefits. Focusing on Sydney, the research evaluates and compares the quality of the community garden policies with the distribution of community gardens in local councils and across broader geographic regions. Councils or regions that might benefit from greater access to community gardens are identified and ways in which councils, and the Sydney Region as a whole, might improve their community garden policies are discussed.     

黔西南高砷煤的分布及地球化学特征研究

根据野外地质特征结合中子活化成分分析结果,探讨了黔西南高砷煤的分布特征、影响因素和某些地球化学特征。高砷煤严格受构造（褶皱和断层）、地层（二叠系龙潭组）、沉积相（海陆交互相）的控制,分布于平行北斜长轴的断层两侧,愈靠近断层面砷的含量愈高。砷在煤中的分布极不均匀,即使同一煤层变化也极大。在时空关系与元素组合上高砷煤与区内卡林型金矿密切相关。     

Place,exile and identity: the contemporary experience of Palestinians in Sydney

Statelessness, displacement and exile, far from being particular moments in history, continue to affect the lives of Palestinians living in Sydney, in the maintenance of national identity and community formation. The impacts that displacement and subsequent ‘statelessness’ have had on the ways in which Palestinians maintain a sense of national identity have similarities with those of other ‘displaced’ peoples. Without the recognition of national boundaries to secure national sovereignty (Palestine) and accommodate the continuation of a shared and inherited history, the most significant element through which Palestinian identity is kept ‘alive’ is the one thing that all Palestinians share: a communal sense of injustice which involves being denied the right to live in, or return to, their homeland. Statelessness, nationalism and the now ‘imagined community’ of Palestine are more crucial for Palestinians living in Sydney than more primordial elements of identity, such as language or local community. Statelessness and exile in Australia have constructed a particular sense of Palestinian nationalism. The continuity of Palestinian identity as a primarily political phenomenon is a situation analogous to that of other diasporic refugee communities.     

The informal Australian city

In recent years, a vibrant literature on urban informality has emerged in urban geography. A key claim of this literature is that informality is not only present in cities in the Global South, and that the concept can be usefully applied to understand important dimensions of urbanisation in cities in the Global North. In this paper, we apply insights from that literature to an examination of informality in Australian cities, as a means of deepening our understanding of changes currently underway in urban governance and politics. Drawing on that literature and our own research into informal practices in Australian cities, we examine the forces that help to produce informality, the diverse forms and agents of informality, the forms of authority that they enact, and their relationship to formal economies, regulations and politics. We use examples of informal housing, informal labour, do-it-yourself music venues, graffiti and its regulation, food foraging, and queer community building in Sydney to illustrate our arguments. We conclude by reflecting on the lessons learnt across these diverse cases for our understanding of urban governance and politics in Australia, and offer an agenda for further research on this issue.     

Rehabilitation of Saline Wetlands, Olympics 2000 Site, Sydney (Australia)—I: Management Strategies Based on Ecological Needs Assessment

The Homebush Bay area, Sydney, site of the Olympic Games 2000, has been largely occupied for nearly a century by an abattoir, brickworks, armaments depot and waste dumps. However, it contains remnants of original ecosystems, including two estuarine wetlands, and the Olympic Co-ordination Authority (OCA), set up to manage the redevelopment of the site, is committed to the rehabilitation of these ecosystems. The ecological approaches and rehabilitation measures used for one of the wetlands are detailed. Apart from a history of disturbance, it has for 10 years been without tidal flushing. However, these wetlands are the largest remaining in the Sydney estuary, and are significant for a number of reasons including biodiversity and waterbird conservation. The ecological parameters of the site, the results of a ‘before-restoration-impact' study, and the iterative links between science and management in the introduction of the rehabilitation measures, are presented. Criteria for success are discussed, along with biomonitoring strategies to test success.     

近两届奥运会气象服务保障综述

悉尼、亚特兰大奥运会的气象服务保障基本上代表了目前世界最高水平的奥运气象服务，为了借鉴前人的工作，更好地为2008年北京奥运会服务，对这两届奥运会的气象服务保障情况进行综述。