Environmental geochemistry in health and disease | Helen L. Cannon and Howard C. Hopps (Editors), 1972. Geological Society of America,Memoir 123, Boulder,Colo., 230 pp., U.S. $ 14.00     

Joe Kubota 《Earth》1973,9(2):144-145

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水-岩-气相互作用引起的水化学动态变化研究--以桂林岩溶试验场为例   总被引：45，自引：2，他引：45  

刘再华  Chris GROVES  袁道先  Joe MEIMAN  姜光辉  何师意 《水文地质工程地质》2003,30(4):13-18

利用多参数自动记录仪对桂林岩溶试验场的降水量、水位、水温、pH值和电导率进行了监测,数据采集间隔根据参数变化的程度由2min到1h不等。结果发现,岩溶裂隙水在洪水期间pH值呈降低趋势,而电导率呈升高的不寻常变化。与此相反,对于岩溶管道水,同样是在洪水期间,它的pH值是升高的,而电导率呈正常的降低。考虑到Ca2 和HCO-3分别为地下水中主要的阴阳离子(>90%),及它们与电导率的线性关系,计算得到了洪水期间方解石的饱和指数(SIc)和水的CO2分压(Pco2)的变化情况。发现洪水时裂隙水的Pco2高于正常情况的Pco2,而它的SIc值比正常情况低。与此相对,对于管道水,尽管同一洪水期间其SIc降低,但Pco2也降低。从这些结果,可以推断,至少有两个关键的过程控制着洪水期间的水化学变化。一个是雨水的稀释作用,另一个是水-岩-气的相互作用。然而,对于裂隙水来说,后者的作用可能更重要,即在洪水期间,高浓度的土壤CO2溶解于水中,则更具侵蚀性的水能溶解更多的石灰岩,从而增强水的电导率。而对于管道水,雨水的稀释作用更重要,因为研究区较高的pH和低电导率的雨水能更快地通过管道流出,所以,要了解岩溶系统水化学的变化,仅考虑水-岩相互作用是不够的,我们还必须重视CO2气体对岩溶系统中水化学变化的影响。总之,水-岩-气相互作  相似文献   

Life Recovery of 1995 Kobe Earthquake Survivors in Nishinomiya City: A Total-Quality-Management-Based Assessment of Disadvantaged Populations     

Takeda  Joe  Tamura  Keiko  Tatsuki  Shigeo 《Natural Hazards》2003,29(3):567-585

The main objectives of this study were (1) to examine what has beenrecovered and what has not yet been recovered in Nishinomiya City five years after the GreatHanshin-Awaji Earthquake, and (2) to find current service needs for the earthquake survivors,especially for the disadvantaged populations. Disadvantaged populations are minorities in society, andtheir needs and opinions are often ignored and not reflected in the services or mitigation policy,despite the fact that they are the ones who are affected most by various hazards. At the same time, becauseof their unique characteristics and positions in society, their needs differ from the majorityof the society. Six hundred eighty-six opinion cards were collected in nine grassroots workshopsessions with various disadvantaged groups in Nishinomiya City, such as the physically challenged,the visually impaired, the elderly living in public housing, junior and senior high school students,mothers with small children, and those who lost their own homes because of the earthquake. Theseopinion cards were sorted out and analyzed by using a TQM(Total Quality Management)-basedassessment method. Since the TQM-based assessment method allows bottom-up integration ofopinions from each individual, it helps us identify unique needs of the disadvantaged groupsand reflect their opinions in mitigation plan and policies. The main findings of this study include (1)the city redevelopment cannot be achieved without integrating the viewpoints of thedisadvantaged; (2) the social support was a key resource for both mental health and community development;and (3) disaster experiences and adaptation produced civic mindedness among people in a community.  相似文献   

3D seismic interpretation of slump complexes: examples from the continental margin of Israel   总被引：6，自引：3，他引：6  

Jose Frey Martinez  Joe Cartwright  Ben Hall† 《Basin Research》2005,17(1):83-108

This paper uses three‐dimensional (3D) seismic data from the continental margin of Israel (Eastern Mediterranean) to describe a series of slump deposits within the Pliocene and Holocene succession. These slumps are linked to the dynamics of subsidence and deformation of the transform margin of the eastern Mediterranean. Repeated slope failure occurred during the post‐Messinian, when a clay‐dominated progradational succession was forming. This resulted in large‐scale slump deposits accumulating in the mid‐lower slope region of the basin at different stratigraphic levels. It is probable that the slumps were triggered by a combination of slope oversteepening, seismic activity and gas migration. The high spatial resolution provided by the 3D seismic data has been used to define a spectrum of internal and external geometries within slump deposits. Importantly, we recognise two main zones for many of the slumps on this margin: a depletion zone and an accumulation zone. The former is characterised by extension and translation, and the latter by complex imbricate thrusts and fold systems. Volume‐based seismic attribute analysis reveals transport directions within the slump deposits, which are predominately downslope, but with subtle variations particularly at the lateral margins. Basal shear surfaces are observed to ramp both up and down stratigraphy. Slump evolution occurs both by retrogressive upslope failure, and by downslope propagation (out‐of‐sequence) failure. Slump anatomy and the combination of factors responsible for slump failure and transport are relatively poorly understood, mainly because of the limited 3D of outcrop control; hence, this subsurface study is an example of how improved understanding of the mechanisms and products can be obtained using this 3D seismic methodology in unstable margin areas.  相似文献   

Assessment of groundwater chemistry in a coastal region (Kunsan, Korea) having complex contaminant sources: a stoichiometric approach   总被引：1，自引：0，他引：1  

Kangjoo Kim  Natarajan Rajmohan  Hyun Jung Kim  Gab-Soo Hwang  Min Joe Cho 《Environmental Geology》2004,46(6-7):763-774

Groundwater chemistry in a coastal region (Kunsan, Korea) having complex contaminant sources was investigated. Water analysis data for 197 groundwater samples collected from the uniformly distributed sixty-six wells were used. Chemical analysis results indicate that groundwaters show wide concentration ranges in major inorganic ions, reflecting complex hydrochemical processes. Due to the complexity of groundwater chemistry, the samples were classified into four groups based on Cl and NO₃ concentrations and the processes controlling water chemistry were evaluated based on the reaction stoichiometry. The results explained the importance of mineral weathering, anthropogenic activities (nitrification and oxidation of organic matters), and Cl-salt inputs (seawater, deicer, NaCl, etc.) on groundwater chemistry. It was revealed that mineral dissolution is the major process controlling the water chemistry of the low Cl and NO₃ group (Group 1). Groundwaters high in NO₃ (Groups 2 and 4) are acidic in nature, and their chemistry is largely influenced by nitrification, oxidation of organic matters and mineral dissolution. In the case of chloride rich waters (Group 3), groundwater chemistry is highly influenced by mineral weathering and seawater intrusion associated with cation-exchange reactions.  相似文献   

Constructed wetland technology and mosquito populations in Arizona     

Martin M. Karpiscak  Kenneth J. Kingsley  Roland D. Wass  Frederick A. Amalfi  John Friel  Aaron M. Stewart  Joe Tabor  Jeffrey Zauderer 《Journal of Arid Environments》2004,56(4):681

Constructed wetlands and other aquatic habitat creation or restoration efforts offer both potential benefits and problems for arid areas. An unintentional consequence of these efforts has been the potential for an increase in local adult mosquito populations. Shallow water-emergent plant zones may provide ideal conditions for mosquito larval growth, and areas of high humidity, dense vegetation, and abundant birds and other wildlife may provide ideal conditions for adult mosquitoes. Three constructed wetlands in southern Arizona were studied over a period of years before and after they were constructed and operational. Mosquito populations were sampled using a variety of methods, primarily trapping of adults with CO₂-baited traps. Populations apparently increased, sometimes by several orders of magnitude, after wetlands became operational. Several methods of mosquito abatement were initiated and their results are discussed. However, no definitive conclusions can be drawn because no untreated areas were available for comparison and many factors that may have affected mosquito populations also changed. Based on the experience gained at these three sites, mosquito control is an especially important design and management component for constructed wetlands in arid environments with low background populations of mosquitoes.  相似文献   

The respiratory physiology of anadromous vertebrates: A comparison of blood gas transport in lampreys and salmonids     

Bruce L. Tufts 《Estuaries and Coasts》1994,17(1):3-12

Much of our understanding of the respiratory physiology of lower vertebrates has been derived from studies of salmonids. With regard to blood gas transport, investigators recently have documented a number of important features that may be helpful to the animal under stressful conditions. Several studies examining the respiratory physiology of agnathans have also revealed that striking differences in the strategy of blood gas transport may exist among the lower vertebrates inhabiting the estuary. This paper describes the characteristics of blood gas transport in both salmonids and lampreys and attempts to compare the respiratory strategy of each.  相似文献   

Multiple detachment levels and their control on fold styles in the compressional domain of the deepwater west Niger Delta   总被引：2，自引：0，他引：2  

Sepribo E. Briggs  Richard J. Davies†  Joe A. Cartwright  Richard Morgan‡ 《Basin Research》2006,18(4):435-450

We interpret recently acquired two‐dimensional (2D) and 3D seismic data from the contractional domain of the Tertiary deepwater west Niger Delta, which is an area of current hydrocarbon exploration and development to show that during its gravitational collapse, multiple detachments were active. Detachments are located within (1) what we herein refer to as the ‘Dahomey unit’, (2) the transition between the Agbada and Akata formations (Top Akata) and (3) the Akata formation. Seismic interpretation and quantitative measurements of fault displacements show that the utilisation of different detachments results in contrasting styles of thrust propagation and fold growth. Two geographical zones are defined. In zone A (NW sector of the study area), the stratigraphically shallowest Dahomey detachment is dominant and is associated with thrust truncated folds. In zone B (SE sector of the study area), a stratigraphically lower detachment approximately at the Agbada–Akata formation boundary is associated with thrust propagation folds. A third detachment, within the Akata formation, is locally developed and is also associated with thrust propagation folds. The different deformational histories are probably related to the mechanical stratigraphy and the pore‐pressure characteristics of the succession.  相似文献   

Origin and variability of a terminal Proterozoic primary silica precipitate,Athel Silicilyte,South Oman Salt Basin,Sultanate of Oman          下载免费PDF全文

Ibrahim M. Al Rajaibi  Cathy Hollis  Joe H. Macquaker 《Sedimentology》2015,62(3):793-825

The Precambrian–Cambrian Athel Silicilyte is a 400 m thick, salt‐encased siliceous succession in the South Oman Salt Basin. It is a self‐sourcing hydrocarbon reservoir and comprises up to 95% microcrystalline quartz and exhibits wavy discontinuous lamination, comprising thin, alternating organic‐rich and silica‐rich layers. Textures and geochemical fingerprinting indicate that it is a primary precipitate formed by microbially mediated precipitation of silica from sea water, within the water column at the sulphidic/oxic interface. The unique occurrence of the Athel Silicilyte in the terminal Proterozoic implies that optimal conditions for this style of silica precipitation occurred only briefly. Basin anoxia, coupled with the growth of microbial mats, low pH and high silica pore water saturations, created optimal chemical conditions for silica precipitation. Volumes of microcrystalline quartz are highest within the transgressive and early highstand systems tract and towards the centre of the Athel Basin. At the basin margins, and within the late highstand systems tract, volumes of microcrystalline quartz decreased as the volume of detrital sediment increased. Mass‐balance calculations indicate that silica‐enriched sea water would have been supplied to the basin by infrequent marine incursions that replenished ambient sea water in the upper part of the water column. In conclusion, precipitation of the Athel Silicilyte was driven by the coincidence of basin restriction, limited clastic input, availability of organic matter and water column anoxia. The observation that there are few documented examples of chert deposits younger than ca 700 Ma, prior to the Cambrian explosion, suggests that although silica budgets within marine basins probably remained high prior to the evolution of silica‐secreting organisms, direct precipitation from sea water was restricted. This is tentatively related to the gradual increase in alkalinity of sea water through the Palaeo‐Proterozoic and Meso‐Proterozoic, such that silica precipitation could only occur through the coincidence of basin anoxia and low siliciclastic input.  相似文献   

Hydrochemical variations during flood pulses in the south‐west China peak cluster karst: impacts of CaCO3–H2O–CO2 interactions     

Zaihua Liu  Chris Groves  Daoxian Yuan  Joe Meiman  Guanghui Jiang  Shiyi He  Qiang Li 《水文研究》2004,18(13):2423-2437

High‐resolution measurements of rainfall, water level, pH, conductivity, temperature and carbonate chemistry parameters of groundwater at two adjacent locations within the peak cluster karst of the Guilin Karst Experimental Site in Guangxi Province, China, were made with different types of multiparameter sonde. The data were stored using data loggers recording with 2 min or 15 min resolution. Waters from a large, perennial spring represent the exit for the aquifer's conduit flow, and a nearby well measures water in the conduit‐adjacent, fractured media. During flood pulses, the pH of the conduit flow water rises as the conductivity falls. In contrast, and at the same time, the pH of groundwater in the fractures drops, as conductivity rises. As Ca²⁺ and HCO₃^? were the dominant (>90%) ions, we developed linear relationships (both r² > 0·91) between conductivity and those ions, respectively, and in turn calculated variations in the calcite saturation index (SI_C) and CO₂ partial pressure (P) of water during flood pulses. Results indicate that the P of fracture water during flood periods is higher than that at lower flows, and its SI_C is lower. Simultaneously, P of conduit water during the flood period is lower than that at lower flows, and its SI_C also is lower. From these results we conclude that at least two key processes are controlling hydrochemical variations during flood periods: (i) dilution by precipitation and (ii) water–rock–gas interactions. To explain hydrochemical variations in the fracture water, the water–rock–gas interactions may be more important. For example, during flood periods, soil gas with high CO₂ concentrations dissolves in water and enters the fracture system, the water, which in turn has become more highly undersaturated, dissolves more limestone, and the conductivity increases. Dilution of rainfall is more important in controlling hydrochemical variations of conduit water, because rainfall with higher pH (in this area apparently owing to interaction with limestone dust in the lower atmosphere) and low conductivity travels through the conduit system rapidly. These results illustrate that to understand the hydrochemical variations in karst systems, considering only water–rock interactions is not sufficient, and the variable effects of CO₂ on the system should be evaluated. Consideration of water–rock–gas interactions is thus a must in understanding variations in karst hydrochemistry. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献