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981.
A hydrogeological investigation of the Bandung area, Java, Indonesia, is described. The investigation was carried out as part of a feasibility study directed towards improvement and development of the city's water supply.The area is situated in a tropic mountainous region, dominated by pyroclastic volcanic deposits and with abundant rainfall. The main activities of the investigation were compilation and evaluation of existing climatological and hydrogeological data, testing of four existing wells, a geo-electrical survey, drilling and testing of a new test well, study of water quality by analysis of samples from both springs and wells, and measurements of spring yields.The results of the investigation indicated presence of large groundwater resources within a distance of 15–20 km from the city. The feasibility study recommended that Bandung's water supply be based on these groundwater resources and this recommendation is being implemented.During the investigation some results concerning rainfall, infiltration, aquifers, geoelectrical surveying, and groundwater quality were obtained, which may be of general interest for hydrologists and geologists working in tropical volcanic and mountainous regions. These results are summarized in the conclusion of this paper. 相似文献
982.
Eberhard Seidel Martin Okrusch Hans Kreuzer Helmut Raschka Wilhelm Harre 《Contributions to Mineralogy and Petrology》1976,57(3):259-275
The uppermost unit of the Cretan nappe system contains a variegated series of high-grade metamorphic rocks. In the Léndas area, amphibolites are present characterized by the assemblagewhile associated metapelitic gneisses consist of
Judging from relevant experimental data for the gneiss assemblage including the Fe/Mg distribution on coexisting garnet and cordierite, the P-T conditions of metamorphism are estimated at about 700° C and 5 kb water vapour pressure.K/Ar determinations on hornblendes from three amphibolites yielded cooling ages of 71.3, 71.2, and 71.1 (±1.7) m.y. respectively; biotites from three paragneisses gave 70.2 ± 1.4, 69.7 ± 1.2, and 67.9 ± 1.4 m.y. respectively. Assuming a sealing temperature against argon diffusion of 300° C, for biotite, and 500° C, for hornblende, a cooling rate of 100–200° C/m.y. is calculated. Thus a late Cretaceous (eo-Alpine) metamorphic event is established in the post-Cretaceous nappes of Crete. 相似文献
$$\text{brown}\;\text{hornblende}\;+\;\text{diopside}\;+\;\text{plagioclase}\;\text{(An 50)}$$
$$\text{garnet}\;+\;\text{cordierite}\;+\;\text{biotite}\;+\;\text{sillimanite (andalusite)}\;\pm\;\text{K-feldspar}\;+\;\text{plagioclase (An 40-50)}\;+\;\text{quartz}.$$
983.
Prof. Dr. Hans Füchtbauer Dr. Detlev K. Richter 《International Journal of Earth Sciences》1983,72(1):53-66
Deep fissures in shallow-water limestones filled with deep-water sediments are described from many places especially in the Triassic and Jurassic of the Tethys and in the Middle to Upper Devonian of the Variscian Mountains. Mass flows occur in the same formations and areas. On the island of Hydra (Greece) it was possible to show that both phenomena are linked by internal breccias of well-fitted limestone fragments. They are indicative of slope or near-slope positions and are very probably caused by flexure-like deformations of shallow-burial limestones. Seismic shocks producing overpressure may be instrumental in the disintegration of the semi-lithified limestones thus providing the material for mass flows. These events are associated with a tectonical subsidence as shown by deep-water matrix in the brecciated shallow-water limestones. They occur in areas and periods of submarine rifting, especially in late Devonian and Triassic time. At least four Triassic brecciation events can be traced from Greece to the Alps and correspond presumably to major transgressions in the cratonic basin of middle Europe. 相似文献
984.
Hans Rudolf Preisig 《Aquatic Sciences - Research Across Boundaries》1979,41(1):155-160
Two hitherto unknown colourless euglenoid flagellates are described from Switzerland. They are closely related to the speciesEntosiphon sulcatum andNotosolenus skujai. However, they are morphologically distinct and therefore a new species name and a new variety name are established for these monads:Entosiphon applanatum n.sp. andNotosolenus skujai var.maior n. var. 相似文献
985.
986.
987.
988.
High concentrations of mercury were measured in sediment and animals collected in the immediate vicinity of a closed-down chemical factory. Sediment contained up to 22 ppm (dry wt) of mercury, deposit-feeding bivalves between 1.4 and 4.4 ppm (wet wt), suspension-feeding bivalves between 0.9 and 1.9 ppm and predatory fish between 0.3 and 0.8 ppm. Outside the ‘hot spot’ area, the mercury concentration in sediment and mussels (Mytilus edulis) rapidly decreased with increasing distance from the former factory. Mercury concentration in flounders (Platichthys flesus) also decreased with distance from the source; the decline was, however, much less marked. 相似文献
989.
The influence of the intrusion of basaltic dykes and sills was investigated on sandstones and siltstones of the Atane Formation (Turonian-Coniacian) from the Sarqaq area (Nûgssuaq peninsula, central West Greenland).In the unaltered rock sequence, the siltstones are dominated by kaolinite, quartz and feldspar. No cementation was observed. The sandstones which are prevalent in this formation are arkoses and lithic arkoses with quartz/feldspar ratios of about 1, with variable contents of rock fragments and with minor amounts of matrix. The matrix consists mainly of kaolinite, less frequently of illite-muscovite and smectite or interstratified illite-smectite. Cement minerals include calcite, Fe-calcite, both mainly in concretions, and subordinate Fe-oxide hydrates.The porosity of the sandstones and siltstones indicates a former maximum depth of burial of 1000 m in the Sarqaq region.Adjacent to thin dykes and sills (1–2 m) the above-described rocks are altered as follows. In sandstones albite (fibrous), quartzine, smectite, goethite were all formed at the expense of kaolinitic matrix, and aragonite cement. In siltstones, interstratified illite-smectite, illite, smectite and low-cristobalite replaced kaolinite. These minerals, especially smectite, exclude temperatures above 200°C; they were probably formed during a cooling period.Adjacent to thicker basalt intrusions—only sills, over 5 m thick, and no dykes are known from this area—the following alterations are observed. In sandstones two textural types of albite were formed in addition to: (1) fibrous albite mentioned above; (2) undulose lath-shaped albite; (3) coarse-twinned non-undulose replacement albite. Moreover, brownish luminescing undulose quartz, muscovite, chlorite, epidote, nontronite and anatase occur. In siltstones the mineral association muscovite-chlorite-pyrophyllite-albite occurs, suggesting temperatures in the range of 250–500°C. Additionally a 22–26 Å mixed-layer mineral (chlorite-muscovite?) formed. At the contacts of thick as well as thin basalt intrusions the detrital grains directly adjoining the basalt are partly fractured; potassium feldspar grains show also a chemical disintegration.The temperatures calculated by application of a cooling model are higher than those indicated by the mineral alterations observed. Convective heat transfer by pore water is suggested as an explanation. 相似文献
990.
Wind speeds at the 300 m tower at the Boulder Atmospheric Observatory have been analyzed. This tower is located in slightly rolling farmland. The following conclusions have been reached:
- For west winds, the terrain is sufficiently uniform for simple surface-layer theory to be adequate without modification even though the air has moved up a small slope to reach the tower. For south and southeast winds, ‘effective’ roughness lengths must be introduced, which are significantly larger than the ‘true’ roughness length.
- Useful wind estimates up to 150 m can be made from winds at 10 m and stability information, provided the ‘effective’ roughness length is known.
- The observations are consistent with a von Kármán constant of 0.35.