遂川—热水走滑断裂带特征及其对丰州盆地铀成矿的控制作用

本文以322矿田为例,对穿越矿田的遂川-热水走滑断裂带的特征及其对铀成矿的控制予以讨论。论述了矿田内铀矿床的形成、分布与遂川-热水走滑断裂带的关系,揭示了丰州拉分盆地的形成与铀成矿的内在联系,认为遂川-热水走滑断裂系是322矿田的主控条件,走滑断裂的脉动性控制了铀成矿的多期多阶段性。最后简要地分析了322矿田的找矿前景和走滑断裂的找矿意义。     

Women's status, environmental changes and child health in the riverine area of Ondo State, Nigeria

The viewpoint that most health problems are environmentally related has always been promoted by medical geography. In recent times, concern about environmental degradation has been of high priority for many national and international organizations as ‘we human beings become a threat to our planet’. There is also a need to specifically focus attention on the impact of so-called development efforts on the health of women and children, in particular those living in highly marginalized regions which often contribute substantially to the overall development of their countries. This paper uses the concept of vulnerability as a departure point from which to map the health risks to children in Igbekun area of Ondo State, the ‘transgressive muddy’ oil-rich coastal area of Nigeria. The paper attempts to highlight the poor quality of life and health of children in particular, and how it is becoming much more difficult to practice health intervention programmes, especially oral rehydration therapy (ORT) in the area. The Igbekun area is an unhealthy and harsh environment, complicated by the devastating effects of oil drilling in recent years. The siltation and sedimentation of the creeks and lagoons have serious health dimensions as human faeces float in and around villages because the ‘bush toilets’ can no longer be reached. The on-going environmental crisis has also deprived women of their traditional means of livelihood; fishing. There is a relatively high level of ignorance (compared with other women living in the same local government area (LGA) of causes of the commonest diseases such as diarrhoea, acute respiratory infection (ARI) and measles. A majority of the women have never heard of family planning, immunization against diseases and interventions such as ORT. Promotive health care services, especially those that strive to reduce the high mortality of children have passed the mothers by. It is also becoming impracticable to promote ORT because of the widespread ‘salty and oily’ water supply in the area. The greatest concern of the women now is that oil drilling activities have further amplified their stressful conditions especially their health and that of their children. Unfortunately, their plight is not acknowledged by the Nigerian authorities and the oil companies are least concerned about alleviating the poor health status of the community, in particular the most vulnerable groups, children under the age of five. This revised version was published online in August 2006 with corrections to the Cover Date.     

Geochemical engineering; taking stock

Geochemical engineering makes use of optimized geochemical processes for the solution of environmental problems. It has developed in a few years from a collection of unrelated scientific and technological incidents into a coherent concept about how and where we can improve our geo-environment. All solutions to problems of pollution are based on neutralization/breakdown, concentration, dilution, isolation or immobilization, which serve to eliminate the pollutant, make it more manageable, or prevent its entry into the mobile phase, usually water, from which it can affect the biosphere. All of these solutions have their counterpart in nature, where many examples are found of high concentrations of potentially harmful substances. A major prerequisite of geochemical engineering solutions is that they should be compatible with the natural evolution of the system in its geo-environment. The advantages of this approach are that we can devise low-cost technologies (nature does most of the hard work itself), interfere least with nature, and quite often end up with useful by-products. Disadvantages are that technologies based on natural geochemical processes tend to be slow. The application of geochemical engineering concepts requires a better understanding of our environment and its ongoing processes than is necessary for a ‘classical' technology. In most environmental technologies the conditions are externally imposed on the system to be treated, and the natural evolution of the system is eliminated, or at best neglected. The concept of seeking a closer conformity with nature is paralleled in other disciplines like agriculture or the medical sector, where we see a similar evolution in the direction of techniques that are more in harmony with nature. Geochemical engineering brings many advantages, particularly in developing countries, or in countries where the state of the economy does not permit the introduction of expensive high-tech environmental technologies. So far, most of the applications of geochemical engineering concepts have focussed on solutions to environmental problems, but there are a number of cases where the environmental issue is more indirect, as e.g. in civil engineering. Geochemical engineering may be practised on a large, almost global scale, down to that of individual minerals, in accordance with the fact that geochemical processes also act on vastly different scales. An overview will be given of some of the problems that are being studied.     

找出最主要的控矿因素,建立三因控矿分析思路

通过几个已知金矿区的研究,认为到不同矿区有不同的控矿因素,首先找出最主要的控矿因素,再配合两个深层相关因素,进行矿体定位。     

Microclimatic characterization of a karstic cave: human impact on microenvironmental parameters of a prehistoric rock art cave (Candamo Cave, northern Spain)

The Candamo Cave contains an important group of paleolithic paintings which have been seriously deteriorated due to mass tourism. In this work, an analysis was carried out of different climatic parameters (CO₂, temperature, humidity, ²²²Rn) during annual cycles with the cave closed to the public and during an experimental period of controlled visits. The effect of visits on the geochemical characteristics of karstic water was also analyzed together with the cave ventilation. The natural variations in the cave air CO₂ were above 3000 ppm, the increase produced through visits was only 100–110 ppm and since the humidity is almost permanently at saturation point, the critical parameter which limits the visitor capacity becomes air temperature. The temperature changes during the annual cycle are of the order of 1  °C in the external part and less than 0.5  °C in the internal part of the cave and a maximum increase of 0.13  °C was observed during the period of the visits. The ²²²Rn and CO₂ concentration minimums in the summer period (July–October) show that this is the most propitious time for visits, since the greatest ventilation is produced in the cave at this time and, therefore, the greatest capacity for recovery. The geochemistry of the water, on the other hand, indicated that this is the period of the year in which processes of wall corrosion can be most easily introduced, although this would be of limited magnitude. The visitor capacity calculated was 29 visitors/day. Received: 29 August 1996 · Accepted: 23 June 1997     

阿拉斯加巴罗AB—67钻孔岩芯的沉积环境分析

巴罗ＡＢ－６７钻孔岩芯的４８个样品被进行了２５个项目的粒度分析和４４个项目的地球化学分析。本文对这些数据进行了Ｑ型因子分析,并得到了４个主因子。研究表明,这４个因子分别代表了沉积环境的四项指标,它们分别为沉积速率,降水,海平面和温度。从岩芯顶部５个样品与巴罗气象台观测记录研究了古温度和古降水的转换函数,从＾２１０Ｐｂ测年和几个环境事件确定了沉积速率的转换函数。     

石门雄黄矿一号窿矿体构造及深部找矿研究

通过对湖南石门雄黄矿一号窿矿区构造研究 ,雄黄矿床赋存于燕山期形成的背斜核部 ,背斜与断裂、断裂与断裂的交汇部位。在多种手段综合研究的基础上 ,指出了矿区导矿构造为 EW向的 F1、F3 断裂 ,容矿构造为次级的 NEE、NE、NW、SN向断裂构造 ;提出了本区中生代的三期主要构造应力场 ,其中 SN向主压应力的构造应力场共轭角高值区为雄黄矿体富集地带。矿床受寒武系娄山关群白云岩、奥陶系灰岩和构造的双重控制。认为在一号窿主矿体 NW、SW方向可能存在有隐伏矿体     

地史重大转折期的环境变化学术讨论会综述

概述了地史重大转折期的环境变化学术讨论会４个方面的主要科学内容：古生代与中生代之交的全球环境变化,泥贫纪弗拉期与法门期之交的全球环境变化,元古宙与显生宙之交扔全球环境变化和地史重大转折期环境变化的研究方法。围绕上述内容,评述了发言人和专题发言人的主要科学资料和科学思想以及本次会议形成的共识。     

川西南雷波地区第四纪地质研究

根据岩石地层学、地貌地层学特征及年代学依据,划分了川西南雷波地区第四纪不同时期的洞外地层,并确定了其沉积类型,建立了第四纪地层系统;在此基础上讨论了本区第四纪环境的演化过程,为研究、评价第四纪岩溶发育规律及其对工程的影响,提供了第四纪不同时段的古环境背景资料。     

Environmental risk factors for diseases transmitted by vectors: a case study in North-Argentina

The study quantifies the environmental risk factors for two diseases with different vectors and cycles of transmission: malaria and Chagas' disease in N.W. Argentina near the Bolivian border. This is the area within Argentina where malaria is still a serious health problem. Chagas' disease is to some extent present in many parts of the country. The field work for the study concerned 5903 people in 1466 dwellings. The study resulted in detailed maps of risk factors: particularly water quality and contacts with migrants from Bolivia in the case of malaria; and thatched roofs and dogs in the case of Chagas' disease. This revised version was published online in August 2006 with corrections to the Cover Date.