广东石灰岩地区的任豆群落

本文对任豆群落的分布及生境特点，主要种群的生物不特性，其种类组成，外貌，结构，动态进行了分析，将其分为三个群落类型加以介绍，并提出开发利用与保护意义。     

Norian magnetostratigraphy from the Scheiblkogel section, Austria: constraint on the origin of the Antalya Nappes, Turkey

Late Triassic magnetostratigraphic investigations in southwestern Turkey have suggested that parts of the Antalya Nappes are constituted of a melange of blocks originally deposited either in the vicinity of the northern tip of Arabia or, more surprisingly, directly north of India, in the southern hemisphere. In order to ascertain this result more clearly, we have correlated the Turkish series with Austrian sections of corresponding age from the Northern Calcareous Alps, for which the hemisphere of deposition is beyond doubt. The new magnetostratigraphic results obtained from the Scheiblkogel section (Austria) confirm the previously suggested middle to late Norian magnetic polarity sequence and support the heterogeneous character of the Antalya Nappes.     

Nanofiltration in Combination with Limestone Filtration for Treating a Soft Spring Water Containing High Amounts of Humic Substances

The paper presented here describes experiments with a nanofiltration pilot plant treating spring water which contains high amounts of humic substances. With this process, water components such as humic substances, iron, manganese, and aluminum may be very well removed. However, the low pH value of the NF filtrate does not conform with the German standards. This is why the pH value will be increased in a second treatment step by limestone filtration. Prior to limestone filtration, CO₂ dosage is required in order to make sure that the pH value stays below the upper limit of the German standards of 9.5. With this treatment, a drinking water results which meets the German standards and has good chemical properties with respect to corrosion. The operation of the nanofiltration pilot plant for the treatment of the very soft spring water did not require the continuous addition of chemicals in order to prevent scaling. Although the spring water entered the NF without chemical pretreatment, there was no decrease in filtrate capacity observed over a period of six months. This is in contrast to other investigations involving colour reduction from very hard surface waters. When treating very hard waters by nanofiltration, the addition of complexing agents or acid is required in order to prevent scaling of the membranes. Such intricate pretreatment procedures cause doubt of the application of nanofiltration for the treatment of hard waters in large plants. However, in the case presented here, the application of NF in combination with the hardening step is quite simple, so that the full-scale plant may be operated mainly automatically and will require only little maintenance.     

Environmental impact on the Roman monuments of Tarragona,Spain

The extant remains of the Roman monuments of Tarragona, Spain are made of different types of Miocenic rocks from the quarries surrounding the city, which vary from calcarenite to bioclastic limestones, showing different degrees of dolomitization, depending on their diagenetic evolution. The decay of these monuments is highly dependent on the mineralogy and the fabric of the stone as well as on the environmental conditions to which the monument subjected. As a consequence, different forms of decay are observed on these monuments, namely, granular disintegration, differential erosion between sparitic and micritic areas of the rock, and development of black crust and orange patinas, some of them attributed to a sulfation process. A number of processes have been established as being responsible for the decay forms observed: sulfation on sheltered areas of the building in the urban environment; differential dilatation because of the NaCl of the marine spray that crystallizes inside the porosity; hydric and thermal expansion of the stone, both related to the amount and crystallinity of the clay minerals forming the rock matrix; and biocolonization on the stone surface. An empirical model is proposed to explain the decay forms studied in relation to these factors (rock and environment).     

论澜沧老厂银铅多金属矿床成矿特征

澜沧老厂系受燕山期构造控制由上部灰岩与下部火山岩组成统一矿化体的银铅多金属大型矿床。深部钻孔揭露花岗斑岩与矽卡岩铜矿化,说明其成因与隐伏酸性岩体有关。历史遗留由灰岩型矿石提银后的富铅炉渣,其含铅金属量加上灰岩型矿石已探明的铅金属量,相当火山岩型矿石已探明铅金属量的２．５倍。说明灰岩型矿体是矿床的主体。只研究火山岩型而忽略灰岩型铅锌矿的研究,或以火山岩型矿体的成矿特征来说明老厂矿床的整体特征,都是不全面的。     

东营凹陷广饶海相灰岩油藏的勘探与成因机制探讨

山东东营凹陷南部的广饶油藏为一奥陶系灰岩残丘山整带含稠油的大潜山油藏,其埋藏深度为６３４．４￣１５７５．０ｍ,现已探明含油面积３０．７ｋｍ＾２。１９９０年发现一个山头含油,１９９１￣１９９３年发现多个山头含油,１９９６￣１９９７年在各山头之间的部位钻探,结果探明潜山带南部整带含油。地质和地球化学资料分析证实,该油藏不仅是今生储潜山油藏,还是烃类经基岩风化壳运移、聚集而形成的稠油油藏。形成稠油的主要     

闽西石灰岩洞穴地质特征及其石笋发育过程的古气候变化

本文以宁化县天鹅洞和永定县仙湖洞为代表介绍闽西石灰岩洞穴地质特征，并通过石笋 ＾１４Ｃ、铀系年代测量等研究成果探讨石笋发育过程的古气候和石笋生长速度。     

Blue-green algae and terrestrial limestone weathering on Aldabra Atoll: An S.E.M. and light microscope study

Blue-green algae have been observed to affect limestone weathering on Aldabra Atoll, Indian Ocean. Three different habitats can be identified on the rock surface, i.e. epilithic, chasmolithic, and endolithic. Algae in each habitat may affect weathering in various ways. Samples of blue-green algae and rock were taken from various terrestrial and coastal environments on Aldabra Atoll. Samples of limestone tablets and calcite crystals after one year in situ were also studied. Light and S.E.M. microscopy revealed that endolithic boreholes were present on many samples, especially those from frequently wetted sites, to a maximum depth of 800 μm. An ‘altered zone’ of micrite and algal filaments was also discovered in many samples. From morphological and petrographical evidence blue-green algal influences on weathering on Aldabra Atoll seem to be very complex and cannot easily be related to small scale landforms.     

Geomorphic inheritance and the development of tower karst

Four genetic types of tower karst are identified, the most typical consisting of residual hills protruding from a planed carbonate surface veneered by alluvium. Two extreme possibilities for tower karst evolution are recognized: a direct development that is independent of any previous morphology and a sequential development that depends explicitly on the morphological characteristics of a previous cockpit karst phase. Examples of both are described, although the latter appears the more common. South China tower karst is examined in this light. Palaeomagnetic analysis of cave deposits in a tower near Guilin indicate the feature to be a time-transgressive landform. Four principal controls of tower development are discussed and a model of tower evolution is presented.