莺歌海盆地天然气运聚成藏条件与分布富集规律

油气勘探实践表明莺歌海盆地的天然气形成、分布及保存均与底辟区超压体系密切相关。文章根据地震、测井及地质资料与钻探成果，系统地分析总结了莺歌海盆地天然气生成、运聚及富集成藏特征。研究表明，莺歌海盆地天然气分布往往具有浅层气田沿中央泥底辟带分布、中深层岩性气藏分布于底辟构造翼部的特征，且具有"流体超压驱动、底辟裂缝输导、重力流扇体储集、高压泥岩封盖、天然气幕式脱溶成藏"的运聚成藏及富集规律。      

Cumulative Benioff strain-release, modified Omori's law and transient behaviour of rocks

Irreversible thermodynamic theories with internal state variables can be used to derive a general constitutive law for both transient and steady-state behaviours of rocks. This constitutive law can represent the concepts of damage and damage evolution in either the fibre-bundle model or continuum damage mechanics. We have previously proposed an empirically based constitutive law for both the transient and steady-state behaviours of rocks ultimately derived from laboratory experimental data. We show here that this law is concordant with the general constitutive law derived from irreversible thermodynamic theories, and that the relaxation modulus has a temporal power–law that depends on a structural fractal property of rocks. Our constitutive law predicts forms for the cumulative Benioff strain-release for precursory seismic activations and the modified Omori's laws of aftershocks, both aspects of the temporal fractal properties of seismicity. These seismic properties can also be derived by the fibre-bundle model or continuum damage mechanics. Our model suggests that these time-scale invariant processes of seismicity may be regulated by the fractal structures of crustal rocks.     

贵州省三都县滑坡特征及分布规律研究

为提高贵州省三都县地质灾害的防灾减灾能力,通过资料收集、地质灾害调查、数理统计、GIS空间分析等手段,查明了研究区滑坡数量及特征,研究了滑坡与地质构造、工程地质岩组、斜坡结构、坡度、坡形和人类工程活动等孕灾因子的关系,总结该县滑坡发育特征与分布规律。结果表明：研究区共发育滑坡57处,多发育在坡度20°~30°范围内,相对高差主要在20~40 m之间,坡形以凸形坡为主。在地质构造方面,丰乐断层、大河断层、烂土断层影响较大,该区域发育地质灾害共35处。软质岩组、顺向坡结构的斜坡区与河流两侧地质灾害数量也较多。按照地质环境差异和滑坡分布规律进行孕灾地质条件复杂、中等和一般分区,研究成果可为地质环境条件相似的地区在风险防控方面提供参考。     

A review of the source,behaviour and distribution of arsenic in natural waters

The range of As concentrations found in natural waters is large, ranging from less than 0.5 μg l⁻¹ to more than 5000 μg l⁻¹. Typical concentrations in freshwater are less than 10 μg l⁻¹ and frequently less than 1 μg l⁻¹. Rarely, much higher concentrations are found, particularly in groundwater. In such areas, more than 10% of wells may be ‘affected’ (defined as those exceeding 50 μg l⁻¹) and in the worst cases, this figure may exceed 90%. Well-known high-As groundwater areas have been found in Argentina, Chile, Mexico, China and Hungary, and more recently in West Bengal (India), Bangladesh and Vietnam. The scale of the problem in terms of population exposed to high As concentrations is greatest in the Bengal Basin with more than 40 million people drinking water containing ‘excessive’ As. These large-scale ‘natural’ As groundwater problem areas tend to be found in two types of environment: firstly, inland or closed basins in arid or semi-arid areas, and secondly, strongly reducing aquifers often derived from alluvium. Both environments tend to contain geologically young sediments and to be in flat, low-lying areas where groundwater flow is sluggish. Historically, these are poorly flushed aquifers and any As released from the sediments following burial has been able to accumulate in the groundwater. Arsenic-rich groundwaters are also found in geothermal areas and, on a more localised scale, in areas of mining activity and where oxidation of sulphide minerals has occurred. The As content of the aquifer materials in major problem aquifers does not appear to be exceptionally high, being normally in the range 1–20 mg kg⁻¹. There appear to be two distinct ‘triggers’ that can lead to the release of As on a large scale. The first is the development of high pH (>8.5) conditions in semi-arid or arid environments usually as a result of the combined effects of mineral weathering and high evaporation rates. This pH change leads either to the desorption of adsorbed As (especially As(V) species) and a range of other anion-forming elements (V, B, F, Mo, Se and U) from mineral oxides, especially Fe oxides, or it prevents them from being adsorbed. The second trigger is the development of strongly reducing conditions at near-neutral pH values, leading to the desorption of As from mineral oxides and to the reductive dissolution of Fe and Mn oxides, also leading to As release. Iron (II) and As(III) are relatively abundant in these groundwaters and SO₄ concentrations are small (typically 1 mg l⁻¹ or less). Large concentrations of phosphate, bicarbonate, silicate and possibly organic matter can enhance the desorption of As because of competition for adsorption sites. A characteristic feature of high groundwater As areas is the large degree of spatial variability in As concentrations in the groundwaters. This means that it may be difficult, or impossible, to predict reliably the likely concentration of As in a particular well from the results of neighbouring wells and means that there is little alternative but to analyse each well. Arsenic-affected aquifers are restricted to certain environments and appear to be the exception rather than the rule. In most aquifers, the majority of wells are likely to be unaffected, even when, for example, they contain high concentrations of dissolved Fe.     

湖南怀化盆地岩溶发育特征与分布规律

怀化盆地位于沅麻盆地和雪峰山冲断带2个构造单元接触带上,区内地质构造条件复杂,岩溶强烈发育。文章以区内碳酸盐岩为研究对象,通过资料收集、野外调查、钻探以及测试等工作手段分析空间上的地层、岩性组合特征,从岩溶形态、地层与岩性、构造条件、侵蚀基准面、地貌与水动力条件、可溶岩与非可溶岩接触带六个方面,系统总结怀化盆地岩溶发育特征。结果发现：研究区以覆盖型岩溶区为主,区内各类岩溶形态发育;区内自高向低存在三个溶蚀最发育段,其标高分别为500~600 m、210~270 m以及190~210 m,分别受历史侵蚀基准面、泸阳－怀化－中方谷地局部侵蚀基准面与舞水河侵蚀基准面控制;区内各地层钻孔遇洞率一般为57.1%~61.5%,最高为87.5%;谷地内各地层岩溶发育强度依次为厚层灰岩>白云岩>红层灰砾岩>薄层灰岩,但受地貌、水动力条件影响,溶蚀构造峰脊洼区的白云岩岩溶发育明显较谷地内更为强烈;舞水河沿岸、断层带附近、可溶岩与非可溶岩接触带以及山前冲洪积区等地下水交替循环强烈的地带,岩溶发育相对更为剧烈;区内岩溶强发育区主要分布于泸阳－城东新区、白沙－菜门溪一带。     

Locational and socio-economic variation in public perceptions of economics and the environment

Government policies for the use of publicly owned environmental resources in Australia are often justified as being for the economic good of the nation. Yet there has been little enquiry about how Australians perceive economic good in the context of the use of environmental resources. The residents of five State government electorates of Perth and one in regional south west Western Australia were surveyed. Their perceptions of economics, the environment and resources in relation to public policy were assessed. The differences in the responses were greater between the different electorates, than between the different socio-economic strata within the same electorate. This paper examines the spatial variability of the results and raises the possibility of developing a socio-locational indicator of attitudes which could provide a tool for policy implementation.     

山西省狐姑山BIF铁矿三维空间分布规律及深部预测

狐姑山铁矿是吕梁地区一个大型BIF铁矿床,该矿床成矿经历多期次构造-变形-岩浆活动,矿体形态极其复杂且空间分布不清,阻碍了深边部找矿效果。在系统的野外地质调查、矿石显微组构分析的基础上,进一步采用三维建模软件构建了狐姑山地层、矿体、断裂、岩浆岩等控矿要素的三维空间模型,结果显示：(1)铁矿主要受袁家村组地层与区域变质作用控制;(2)矿体形成后主要经历了EW向与近SN向的挤压构造应力作用,产生了褶皱变形,形成了连续平行分布的凹凸体,其垂向变形最大幅度达220 m;(3)成矿后的断裂错断矿体且断距较小,基性岩脉对矿体具有明显的破坏作用;(4)深部矿体倾角逐渐变缓,典型勘探线剖面高精度磁测与大地电磁测深结果显示深部异常体连续且有稳定延伸。综合矿床地质特征、三维空间分布、磁化率及电阻率异常特征认为,狐姑山矿床深边部均具有较大的找矿前景,并圈定了3个找矿靶区。     

土−水特征曲线测量过程中孔隙分布的演化规律探讨

测量了在宽广吸力范围内原状样和压实样的脱湿持水曲线,对比分析了单双峰结构持水性能的差异;并利用压汞试验测试两种土样在脱湿过程的孔隙分布,分析了两者的差异并探讨了脱湿过程孔隙的演化规律;在考虑收缩变形的基础上,基于孔隙分布曲线确定了土?水特征曲线的基本参数。试验结果表明：原状样在宽广吸力范围内基本上呈单峰孔隙结构;饱和压实样具有单峰孔隙结构,随着吸力的增加,双峰结构越来越明显,当吸力达到很大时,演化成完全双峰孔隙结构。原状样的持水曲线为经典的S形,而压实样的持水曲线在过渡段出现了水平台阶状;低吸力段,压实样的持水曲线低于原状样,而高吸力段,两者的持水曲线基本重合。基于孔隙分布曲线确定了控制持水曲线进气值和残余值的孔径,并计算出对应的吸力值,其值更符合实际物理意义。     

映秀—北川断裂带沿线崩滑体分布规律浅析

“5.12”汶川大地震诱发的大规模次生地质灾害主要以崩滑体的形式表现。选取地震发生的映秀—北川断裂带沿线的崩滑体进行分析。根据地震影响的强弱、崩滑体分布的规模、大小及地形等因子,把映秀—北川断裂带沿线分为3个区域,分析崩滑体分布的微观规律。在震中,崩滑体的分布与地震释放能量大小正相关;在距震中稍远的地区,崩滑体的分布主要受岩石能干性及地形的控制。崩滑体的分布与地震影响强弱、岩性及地形相关的这一规律,对于防止类似次生地质灾害的发生、次生地质灾害的转化以及灾后重建等都有重要的参考价值。     

Climate forcing,primary production and the distribution of Holocene biogenic sediments in the Gulf of California

The Gulf of California is a marginal seaway under the influence of a monsoon climate that produces cool, dry winters and warm, humid summers. Winds, tidal mixing and coastal-trapped waves forced by climate and the Pacific Ocean control nutrient advection and primary productivity (PP). Strong northwest winds from the subtropical East Pacific High Pressure system begin in November and last until April and drive coastal upwelling along the mainland margin, especially in the central and southern Gulf. In the northern Gulf, particularly around the midrift island, tidal mixing and turbulence occurs year round, advecting nutrients into the mixed layer and high productivity. During summer and early fall months, winds are variable, of less intensity and mainly blow cross-basin except in the most northern Gulf. Summer PP is generally low in the central and southern Gulf except along the mainland where coastal-trapped waves associated with tropical surges and hurricanes generate mixing over the continental shelf. Mesoscale eddies or gyres often associated with jets and filaments extend to depths of 1000 m and transport nutrient-enriched upwelled waters and plankton detritus across the Gulf. The largest and most persistent gyres rotate in an anti-cyclonic direction (east to west) and are a principal source of the plankton export to the peninsula margin.Two major biogenic sediment patterns are present in core-top sediments. Hemipelagic biosiliceous-rich muds are accumulating beneath upwelling areas of high productivity in the central Gulf and along the mainland margin. Calcium carbonate- and organic carbon-rich (OC) sediments are concentrated along the peninsula margin, generally beneath lower productivity waters with the highest OC content in areas with the lowest productivity. The high, uniform biosiliceous content in Guaymas basin, extending southward into Carmen basin reflects the redistribution by mesoscale gyres of phytoplankon debris produced in mainland coastal upwelling and tidally forced areas around the midrift islands.Holocene biogenic patterns are similar to the present day with the major difference in rates of accumulation. Phytoplankton production prior to about 8200 yr BP was significantly higher in the central and southern Gulf, decreased though the mid-Holocene and has been reasonably steady for the past 2500 yr. The strong north–south and east–west gradients in present-day phytoplankton productivity patterns are also reflected in the Holocene sediment record. A series of depositional cycles occur in the biogenic record with the strongest peaks of variability at about 150 (144±18), 200 (198±5) and 350 (350±40) yrs. Longer periodicities are present prior to 3200 yr BP but the 350 yr cycle dominates in the late Holocene where it is best expressed as productivity/dissolution cycles in the carbonate record.     

On the distribution of atoms in magmatic systems: Normal geochemical law

A chemical analysis gives a solid base for a study of the distribution of elements in magmatic systems. Development of groups of constituent elements leads to the appearance of regularities which are translated by such close correlations that values for average rock compositions may be calculated using regression lines. These lines are divided into three segments corresponding to granitoids, gabbroids, and dunitoids. This normal geochemical law is not only valid for the average values obtained statistically but also for those obtained from petrographical families resulting from mineralogical classifications. The law also is true for the correlations: valencies/volumes and valencies/theoretical densities. The existence of such a law governing the fundamental geochemical equilibria enables deductions and comparisons to be made with the composition of regional series.     

Locational Decisions and Residential Preferences of Taiwanese Immigrants in Australia

Since the 1980s, the increase of Asian migrants in large cities has contributed significantly to the cultural landscape of Australia, especially in the city suburbs. Based on the Census and in-depth interviews of 103 Taiwanese migrants, this research examines the location decisions and residential preferences of Taiwanese migrants in Sydney, Brisbane and Melbourne. The reasons for choosing the state, the particular city, and specific area of residence are probed into. The survey shows that migrants moved to Australia mainly for children’s education, lifestyle and political instability reasons. The main reasons for choosing to settle in Sydney were favourable business opportunities, and the northern part of Sydney was preferred. Those who chose Brisbane are attracted by the good climate there, and the residents preferred the Sunnybank area. Melbourne was chosen for the good education it offers, and areas on transportation lines near good schools are selected. Choice of residence was based mainly on their needs and their resources which may change over time. In general, they always choose to locate in close proximity to their family, friends and Taiwanese communities. Their locational choice depends on income and housing budget, proximity to good schools and shopping centers, and information from friends or earlier migrants. Based on such factors, this study clearly demonstrates that the Taiwanese immigrants are fundamentally different from early Chinese settlers who once aimed to settle at Chinatown locations.     

Evaluating the timing of oil expulsion: about the inverse behaviour of light hydrocarbons and oil asphaltene kinetics

This paper deals with natural temperature records in the heavy (asphaltenes) and the light fractions (C₇—light hydrocarbons) of petroleum. Two sets of marine oils formed from different source rocks and petroleum systems were studied using asphaltene kinetics and light hydrocarbon analysis. Both fractions have been reported to contain information about the temperature the respective oils have been exposed to in the subsurface. These indicated temperatures generally correspond to the conditions in the source rock when expulsion occurred. Bulk kinetic analysis of reservoir oil asphaltenes as well as light hydrocarbon (LH) analysis (of dimethylpentanes) were used here in order to evaluate the expulsion temperatures. Surprisingly, when considering information coming from both fractions, an inverse trend between LHs expulsion temperatures (Ctemp) and asphaltenes (Tasph.) can be observed—high T_asph (asphaltene temperatures) occur with low LH C_temp (light hydrocarbon expulsion temperatures) and low T_asph can be observed when Ctemp is high. These differences are of fundamental importance for the use of such geochemical data in calibrating numerical basin models. The reason for this inverse behaviour is possibly due to the different expulsion behaviour of light hydrocarbons and the heavy fraction of oils, especially when the source rocks contain only moderate amounts of organic matter. In addition it has to be considered that the temperature predictions obtained using asphaltene kinetic analysis are related to the onset temperature of petroleum expulsion, while light hydrocarbons provide, at best, average expulsion temperatures.     

采动影响区被保护煤层渗透率分布规律

为了更好地进行采动影响区被保护煤层瓦斯抽采工作,以淮南矿区某矿某工作面为例,使用物理相似模拟、FLAC3D数值模拟、采动区渗透率历史拟合等方法,探讨上部被保护煤层采动影响范围及渗透率变化规律。结果表明：被保护煤层有着明确的区域划分,走向剖面工作面前方卸压区长约20 m,工作面后方卸压区长约30 m,裂隙张开区长约30 m,裂隙张开区之后为重新压实区;明确了各区域的渗透率变化范围,工作面前、后方卸压区渗透率为（150~250）×10^-3 μm²,裂隙张开区渗透率为（400~800）×10^-3 μm²,重新压实区渗透率为（15~100）×10^-3 μm²,采动区被保护煤层渗透率在采动过后,较原始渗透率增大32~1 600倍。     

甘肃省磷矿床分布规律及成矿远景分析

甘肃省磷矿床主要分布于北山区、龙首山区和北祁连山区，矿床规模以小型矿床为主，分属不同的建造类型。本文通过分析甘肃省磷矿资源及分布特征，并介绍典型矿床特征，总结甘肃省磷矿的成矿地质条件及时空分布规律，提出了3个磷矿成矿远景区。     

Residential preferences in the city of Warsaw,Poland

Warsaw was heavily damaged during World War II. Post-War socialist reconstruction emphasized public multi-family housing. A 1987 survey revealed that about one-third of Warsaw residents lived in single-family units, though most expressed their preferences to live in single family houses free from noise pollution and in an aesthetically acceptable environment. In two areas, the CBD and the Praga North, a large proportion of residents preferred to live in existing multi-family units, though such preference was much greater among the blue collar workers than white collar.     

西藏地热系统B、Li、Rb和Cs元素空间分布规律与超常富集机制

西藏地热资源异常丰富,属于地中海—喜马拉雅地热带的重要组成部分。地热系统最为典型的地球化学特征是大部分地热泉或与之相应的泉华沉积物超常富集B、Li、Rb、Cs等元素,具有重要的矿产资源意义。有关这些特征元素来源与水化学演化成因机制,长期存在争议,在理论上缺乏系统论述。本文基于多年野外考察与数据积累,以及对前人研究成果的系统总结,提出了西藏地热系统特征元素组合与富集成因模式,宏观板块构造与微观地球化学分布规律结合,揭示了其成因机制。数据综合分析表明,B、Li、Rb、Cs元素在空间上的分布富集规律总体具有同步性,主要集中分布于雅鲁藏布江缝合带与南北向断裂带交汇区的高温地热系统。B同位素、元素组合、水循环特征及大量地球物理证据表明物源受控于岩浆残余流体,水-岩作用难以作为唯一物源支撑地热系统如此大规模的特征元素超常富集。结论提出西藏地热系统超常富集的元素受控于板块俯冲碰撞、地壳局部重熔、重熔型岩浆流体分异演化、地下水深循环等一系列内外生地质耦合作用过程。本文对西藏地热系统元素超常富集成因机制的解释,有利于增强人们对高温地热系统除水资源与热能意义之外,也同时关注矿产资源价值,实现“水-热-矿”于一体的系统理解,也对未来正确评价地热水体或沉积物矿产资源价值有理论指导意义。

     

Text, talk, things, and the subpolitics of performing place

This article tells the story of how a group of Dutch and Belgian citizens organized themselves to promote an area that they valued, to put it on the map, to raise awareness about its qualities, and to protect it from urban and industrial development. Our theoretical perspective focuses on the performative and political aspects of this place-making process and the discursive and material practices involved. We connect this to Beck’s concept of subpolitics.Our findings show how the group performed this place not only through text and talk - giving the area a name, using their knowledge and expertise to raise awareness about its values, lobbying and cooperating with decision-makers -, but also through things - installing art objects and information signs that articulate certain characteristics and values of the area. Our findings demonstrate the struggles involved in these performances. The group involved multiple perspectives on what the important values and characteristics of the area are and on what strategies would work best in trying to influence decision-making and protect the area. However, the use of expertise as the main strategy to gain influence excluded the more critical and activist strategies and privileging archaeological and historical values and characteristics came at the expense of attention on agricultural and natural values.Our findings make clear that performing place cannot be taken to be homogeneous and that it inevitably involves multiple perspectives and demands. The struggles, power relations and dynamics of inclusion and exclusion that this multiplicity implicates reveal a form of sub-politics that involves both politicization and depoliticization. Also, it is a form of subpolitics that is more diverse and ambiguous than Beck’s conceptualization presupposes by its emphasis on the role of outsiders as a homogeneous group.     

The distribution of population and medical facilities in the Arab Republic of Yemen

The aim of this paper is to study the relationship between population distribution and medical facilities in the Arab Republic of Yemen. In order to do this hospital work-loads have been calculated for each province. The results show that the provision of health services, in the country as a whole, is rather critical, while the situation in certain provinces has reached a dangerous level. The paper concludes with a call for the Yemeni authorities to substantially improve the delivery of medical care on a nationwide scale.