阿拉善东七一山大型萤石矿床萤石钐-钕同位素年龄及地质意义

为了查明东七一山矿床的形成过程 ,对主矿体中的 5件萤石样品进行了钐_钕同位素测定 ,所获得的等时线年龄为 (5 11± 5 )Ma和MSWD值为 0 .10。此外 ,14 3 Nd/ 14 4Nd初始比值为 0 .5 1176 0± 5 (2σ)和 εNd(t)为 - 4.2±0 .5 (2σ)。依据上述同位素分析数据 ,同时结合容矿围岩和矿体的地质特征 ,可以推测 ,东七一山萤石矿床是加里东期构造_岩浆活动的产物。成矿热液来源与壳源岩浆结晶分异作用有关。该矿床属侵入岩为主岩的中高温热液萤石矿床     

以“新经济”为鉴 发挥好后发优势

发挥后发优势，实现生产跳跃式发展，是我国特别是中西部地区加快重要战略方针，为发挥好后发优势，应当研究“新经济”所昭示的新趋势和新经验，研究实现跨越式发展的规律性，客观和主观条件，理清思路，采取一些特殊措施，尤其是突出“第一生产力”的地夹和作用。     

Spatial variations and controls of acid mine drainage generation

Spatial variations of historical and ongoing pyrite oxidation rates were quantified near the Nanisivik Mine on Baffin Island in northern Canada. The variations observed depend mainly on the degree of water saturation, pH and temporal trends in mineral reactivity. Maximum oxidation rates were observed in an untreated tailings spill, while minimum oxidation rates were noted for tailings deposited under water. Spatial trends in oxidation rates were in the order of three orders of magnitude. Spatial trends were only possible to quantify by a combination of closed chambers (well-drained conditions) and micro sensors (water-covered conditions). Oxygen uptake rates in tailings at various ages (up to 7 years) indicate a decrease by more than a factor of 3 over time. Total oxygen uptake over 7 years was calculated and found to be in a fair agreement with the overall pyrite depletion evaluated as high-resolution mineral mass balance (by quantitative powder X-ray diffraction).     

Actinic Radiation and Photolysis Processes in the Lower Troposphere: Effect of Clouds and Aerosols

Within the German Tropospheric Research Program (TFS) a series of projects were performed focussing on aspects of radiation transfer and the effects of UV-radiation on air chemistry. The individual projects covered laboratory investigations, instrument development for photolysis processes as well as field studies of actinic radiation and comparison to model calculations. One and three-dimensional models were tested against field campaign data. The results confirm the improvement of measurement technology achieved through deployment of new techniques like spectroradiometry that offer a wider range of investigations than was previously attainable using chemical actinometry or fixed wavelength filter radiometry. Reasonable agreement was also found between measurements and models for a few selected and well defined cloudy conditions. On the other hand, using simple stratiform geometry models yielded significant deviations between measurement and model in both directions particularly in the case of high zenith angles and with high aerosol load. Further tools both for experimental investigations and for model calculations were developed within the framework of the Troposphere Research Program (TFS) and deficiencies were identified demanding further investigations when broken clouds and more complex cloud layers prevail.     

What Causes Cracks in Rock Blasting?

In blasting, a few or many cracks are driven from the borehole into the rock. But what causes the cracks? The most common theory of breakage consists of two stages; first the shock wave causes radial cracks to form around the hole then the gases penetrate into the cracks, and widen them and make them longer. Another theory presented by Brinkmann suggests that the back damage is primarily controlled by shock and that the gas penetration is the mechanism controlling breakout of the burden. He did his experimental work using blasthole liners. Recent research at SveBeFo has examined this matter further. In a quarry a number of benching holes have been blasted simultaneously. In some of these holes tubular Swellex bolts were inflated and decoupled charges put inside the tubes without stemming. Other holes were identically charged but without the lining. Finally some holes were also stemmed. After blasting the cracks in the remaining rock were studied. There was no difference in crack lengths between holes charged normally (no stemming) and holes where the charges were inside the bolts. On the other hand when stemming was used, the crack lengths increased for some explosives but remained the same for an emulsion explosive. In another set up blasted granite blocks were charged in the same way as above. Then we could also measure the bore hole pressure. The pressure gauge consists of a small carbon resistor inside a steel cylinder. It is called LHM (Location-fixed Hydrodynamic Measuring cup) and is placed at the bottom of the hole. A smaller exit hole from the bottom is drilled for the cables. The paper presents the technique and the results obtained from both the quarry blasting and the blasting of the blocks.     

堡子梁隧道顶部古滑坡地质灾害整治工艺方法

堡子梁隧道顶部古滑坡地质灾害整采用迈式主浆锚杆、迈式注浆泵以及相应的施工工艺和深孔压浆技术，获得了较好的工程治理效果。     

非均匀介质中微侧向测井仪器的三维有限元数值分析

在这篇文章中，分析了一个具有井眼的非均匀介质中似稳电流场的边值问题。采用了三维有限元的直接解法求解三维似稳电流场；给出了微侧向测井仪器的电极表面电流分布、假几何因子以及８英寸井眼的泥饼校正曲线；求出了在具有倾斜地层条件下，微侧向测井仪器对界面的响应。数值结果与发表的文献非常吻合，从而证明了这种方法的正确性。因此，它为新的仪器研制和微侧向测井解释提供了可靠的数据和理论依据。     

Relationship between coral growth rate and sea surface temperature in the northern part of South China Sea during the past 100 a

To research the relationship between coral growth rate and sea surface temperatnre (T_ss), 5 cores of livingPorites lutea were collected from the Xisha Islands and the southern Hainan Island waters and measured. The results of the study show that there is an obviously positive correlation between the coral growth rates and theTss records from the northern part of South China Sea. The annual growth rates of the five samples ofPorites lutea during the past 100 a are in the range of 7—15 mm/a, and their mean value is 11 mm/a. The correlation coefficients between the coral growth rates and the T_ss records from the waters during 1961—1993 are in the range of 0.77—0.89. As a result, a thermometer of the coral growth rate is established. A hindcasting T_ss, in the waters from 1993 to 1961 has been obtained with an error of about 0.12—0.17°C. Based upon the calculated result, the rising rate of T_ss in the northern part of South China Sea during the past 100 a is 0.20°C. which is higher than that of the air temperature in China (0.09°C/100 a), but lower than that of the global temperature and that of T_ss in the tropical western Pacific Ocean. Project supported by the National Nutural Science Foundation of China and the Multidesciplinary Oceanographic Expedition Team of Chinese Academy of Sciences to the Nansha Islands.     

溃屈型滑坡滑面强度特征及在稳定性预测中的意义——李家峡水电站初期蓄水水库滑坡预测成功原因分析

溃屈型滑坡由于滑动破坏方式的不同，滑面的物质组成有明显的差异。按照物质组成的特征对滑面强度参数进行分段试验、取值，是作好此类滑坡稳定性预测的重要环节。以李家峡水库Ⅱ号滑坡为研究实例，介绍了作者们在滑坡预测成功方面所取得的研究成果。     

广西拉么铜锌矿床矿物学特征及其地质意义

广西拉么铜锌矿床矿物学特征及其地质意义李明琴税哲夫聂爱国张杰（贵州工业大学资源工程系，贵阳５５０００３）关键词黄铜矿闪锌矿矿物学特征铜锌矿床广西拉么广西拉么铜锌矿床位于黔桂边界广西南丹县境内，在大地构造上位于江南地轴西南缘、南丹河池轴缘凹陷带中。矿床...