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1.
《Computers and Geotechnics》1987,4(2):61-83
Determination of critical buckling loads of columns in a medium which offers resistance to lateral deflections depend on:
- (a) Length of the pile, L.
- (b) Flexural stiffness of the pile, EI.
- (c) Stiffness of the soil, K, and
- (d) Boundary conditions of the pile, both at the top and the tip.
2.
3.
《Engineering Geology》2001,59(1-2):1-49
Geologic concepts and scientific-technical guidance for the planning-design and construction of engineered works was recognized in Europe by the 1800s and by the early 1900s in North America. This early geologic knowledge and experience provided the rudimentary principles that guided practitioners of the 19th century in serving the emerging projects in western United States. Case studies review the scientific-technical lessons learned and the legacy of geologic principles established in the planning and construction of major civil, mining, and military engineered works in the western states. These contributions to GeoScience knowledge and engineering geology practice include:
- •Tunnels and aqueducts across active fault zones, beneath young volcanic features, groundwater-charged faults, and land subsidence mitigation.
- •Controversial foundation design, Folsom and Auburn dams, Golden Gate Bridge.
- •Protective underground construction chambers, safety dependent geologic setting.
- •Geologic mapping as database management leasing, maintenance railroad trackway.
- •Causeway Great Salt Lake, geo-risks calculated, mitigated ‘as-constructed’.
- •Nuclear powerplants seismic design.
- •Urban Land-Use, on-going processes, acceptable geo-risks.
- •Dwelling Insurance, insuree's responsibilities.
- •Selecting technique/method to mitigate risk, preferably based on extensive database, evaluation of characteristics and historical origin adverse features/conditions that constitute a geo-risk.
4.
《Tectonophysics》1987,138(1):45-53
In this paper, the seismic pattern in Northern China from 30 ° to 42 ° N latitude and 104 ° to 125 ° E longitude, and the characteristics of the epicentral distribution before large events are presented. The results suggest that:
- 1.(1) the earthquakes in the region are mainly located in the orthogonal curvilinear network formed by the seismic belts;
- 2.(2) the larger earthquakes (M ⩾6) occurred mainly in the nodal regions of this grid:
- 3.(3) the strike of the fracture planes of the earthquakes coincided with the directions of the seismic belts;
- 4.(4) the pattern of medium strong earthquakes (M ⩾ 4.7) prior to thirteen large earthquakes (M⩾ 7) are analysed to be of three types:
- 4.1.(a) mainly arranged along the two intersecting belts,
- 4.2.(b) randomly distributed,
- 4.3.(3) forming seismic gaps.
5.
The Karkonosze–Izera Massif is a large tectonic unit located in the northern periphery of the Bohemian Massif. It includes the Variscan Karkonosze Granite (about 328–304 Ma) surrounded by the following four older units:
- -Izera–Kowary (the Early Paleozoic continental crust of the Saxothuringian Basin),
- -Ještĕd (the Middle Devonian to Lower Viséan sedimentary succession deposited on the NE passive margin of the Saxothuringian Terrane), out of the present study area,
- -Southern Karkonosze (metamorphosed sediments and volcanics filling the Saxothuringian Basin), out of the present study area,
- -Leszczyniec (Early Ordovician, obducted fragment of Saxothuringian Basin sea floor).
- -formation of the Saxothuringian Basin and its passive continental margin (about 500–490 Ma)
- -Variscan thermal events:
- -regional metamorphism (360–340 Ma)
- -Karkonosze Granite intrusion (328–304 Ma)
- -Late Cretaceous and Neogene-to-Recent hypergenic processes.
6.
《Lithos》1987,20(2):153-168
The Thorsmörk ignimbrite, southern Iceland, contains a suite of granophyre xenoliths displaying magmatic or high-temperature sub-solidus mineral assemblages. These granophyres are consanguineous with the erupting comenditic magma. Four types of mineral assemblages are distinguished:
- 1.(A) oligoclase, edenitic hornblende, salitic pyroxene, magnesian biotite, magnetite and sphene;
- 2.(B) oligoclase, manganoan to sodic ferro-augite, fayalite, richterite, ilmenite and magnetite;
- 3.(C) anorthoclase, ferrohedenbergite to aegirine hedenbergite, ilmenite, magnetite and (riebeckite);
- 4.(D) cryptoperthite, aegirine hedenbergite to (aegirine), aenigmatite, arfvedsonite, ilmenite and magnetite.
7.
《Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy》1999,24(10):913-920
Climatic change in SE Europe can be characterized by the term aridification, which means increasing semi-aridity, manifested in an increase of mean annual temperature and at the same time in a decrease in the yearly precipitation.The paper deals with research results obtained within the framework of the MEDALUS II project (funded by the Commission of the European Communities). The project had the following objectives:
- 1.(i) Assessment of the impact of global change on the climate of the investigated area, including possible future climates.
- 2.(ii) Physical processes of aridification, including studies of groundwater level change, soil moisture profile dynamics, soil development, vegetation change and soil erosion.
- 3.(iii) Land use change, involving research on present land use and suggestions for the future.
- 1.(i) Statistical analysis of climatic oscillations and computer runs of climatic scenarios,
- 2.(ii) Analysis of ground water data, mapping and analysis of soils and vegetation, assessment of present and future soil, and
- 3.(iii) Land capability assessment through ranking environmental conditions according to the demands of the most widely grown arable crops in Hungary.
8.
Several analogue modeling studies have been conducted during the past fifteen years with the aim to discuss the effects of sedimentation and erosion on Foreland Fold and Thrust Belt, among which a few have analyzed these processes at kilometric scale (Malavieille et al., 1993; Nalpas et al., 1999; Barrier et al., 2002; Pichot and Nalpas, 2009). The influence of syn-deformation sedimentation and erosion on the structural evolution of FFTB has been clearly demonstrated. Here, we propose to go further in this approach by the study of a more complex system with a double decollement level. The natural study case is the Bolivian sub-Andean thrust and fold belt, which present all the required criteria, such as the double decollement level. A set of analogue models performed under a CT-scan have been used to test the influence of several parameters on a fold and thrust belt system, among which: (i) the spatial variation of the sediment input, (ii) the spatial variation of the erosion rate, (iii) the relative distribution of sedimentation between foreland and hinterland. These experiments led to the following observations:
- 1. The upper decollement level acts as a decoupling level in case of increased sedimentation rate: it results in the verticalization of the shallower part (above the upper decollement level), while the deeper parts are not impacted.
- 2. Similarly, the increase of the erosion rate involves the uplift of the deeper part (below the upper decollement level), whereas the shallower parts are not impacted.
- 3. A high sedimentation rate in the foreland involves a fault and fold vergence reversal, followed by a back-thrusting of the shallower part.
- 4. A high sedimentation rate in the hinterland favours thrust development toward the foreland in the shallower parts.
9.
《Tectonophysics》1987,142(1):99-109
Five hundred and fifty temperature values, initially measured as either bottom-hole temperatures (BHT) or drill-stem tests (DST), from 98 selected petroleum exploration wells form the basis of a geothermal gradient map of central Tunisia. A “global-statistical” method was employed to correct the BHT measurements, using the DST as references. The geothermal gradient ranges from 23° to 49°C/km. Comparison of the geothermal gradient with structural, gravimetric and petroleum data indicates that:
- 1.(1) the general trend of the geothermal gradient curves reflects the main structural directions of the region,
- 2.(2) zones of low and high geothermal gradient are correlated with zones of negative and positive Bouguer anomalies and
- 3.(3) the five most important oil fields of central Tunisia are located near the geothermal gradient curve of 40° C/km.
10.
Most of the Cu (± Mo,Au) porphyry and porphyry-related deposits of the Urals are located in the Tagil-Magnitogorsk, East-Uralian Volcanic and Trans-Uralian volcanic arc megaterranes. They are related to subduction zones of different ages:
- (1)Silurian westward subduction: Cu-porphyry deposits of the Birgilda-Tomino ore cluster (Birgilda, Tomino, and Kalinovskoe) and the Zeleny Dol Cu-porphyry deposit;
- (2)Devonian Magnitogorsk eastward subduction and the subsequent collision with the East European plate: deposits and occurrences are located in the Tagil (skarn-porphyry Gumeshevskoe etc.) and Magnitogorsk terranes (Cu-porphyry Salavat and Voznesenskoe, Mo-porphyry Verkhne-Uralskoe, Au-porphyry Yubileinoe etc.), and probably in the Alapaevsk-Techa terrane (occurrences of the Alapayevsk-Sukhoy Log cluster);
- (3)Late-Devonian to Carboniferous subduction: deposits located in the Trans-Uralian megaterrane. This includes Late-Devonian to Early Carboniferous Mikheevskoe Cu-porphyry and Tarutino Cu skarn-porphyry, Carboniferous deposits of the Alexandrov volcanic arc terrane (Bataly, Varvarinskoe) and Early Carboniferous deposits formed dew to eastward subduction under the Kazakh continent (Benkala, etc.).
- (4)Continent-continent collision in Late Carboniferous produced the Talitsa Mo-porphyry deposit located in the East Uralian megaterrane.
11.
《Tectonophysics》1987,138(1):79-92
Analysis of the space-time patterns of seismicity in the Himalaya plate boundary has established the existence of three seismic gaps:
- 1.(1) The “Kashmir gap” lying west of the 1905 Kangra earthquake;
- 2.(2) the “Central gap”, situated between the 1905 Kangra and the 1934 Bihar earthquakes;
- 3.(3) the “Assam gap” between the 1897 and 1950 Assam earthquakes.
12.
13.
《Tectonophysics》1987,134(4):339-345
Downward continuation of temperature data from 73 wells extending to depths of 250 ft (76 m) provides constraints on the thermal regime of the Valles Caldera. Surface-temperature gradient data and bottom-hole temperatures were used as constraints in the downward continuation. Three factors were found to control the shallow thermal regime:
- 1.(1) heat associated with the main geothermal source;
- 2.(2) local topography; and
- 3.(3) west-southwest groundwater flow. Although the well density is relatively high, comparison with the topography shows that the wells are not randomly distributed and tend to be clustered in valleys. Many details in the thermal regime appear to be related to groundwater drainage in these valleys. Temperature gradients and temperatures generally increase in the same direction as the regional drainage of the caldera suggesting a long-wavelength, shallow component to this regional gradient trend. Inversion of gradient and temperature data show additional deep heat input in the west-southwest sector of the caldera which appears to be spatially associated to the youngest volcanism. A previously reported northeast displacement of the main heat source from the surface anomaly has not been confirmed.
14.
《Applied Geochemistry》2005,20(2):261-274
Very low concentrations of total S, mainly sedimentary sulphides, were quantitatively extracted from Quaternary sands of the Elbe Basin, using HNO3, Br2 and HCl, to distinguish 3 aquifer zones:
- •an upper aerobic section, containing low concentrations (only a few ppm) of non-sulphidic S compounds,
- •the central and lower part of the aquifer, dominated by 34S-depleted sedimentary Fe sulphides, formed by reduction of infiltrating SO4, derived from groundwater recharge, and
- •the lowest 5–10 m of the aquifer, containing high concentrations of 34S-enriched sulphides.
15.
Dr. Wolfgang E. Krumbein 《International Journal of Earth Sciences》1971,60(2):438-471
The influence of bacteria on recent sediments was first discussed in 1885, whenFischer andGazert were discussing the cycle of substances in the sea as well as in sediments. The influence of bacteria on the cycling of C, N, S, P in recent sediments and the open sea was soon accepted by marine geologists. Nevertheless, only very few experiments have, so far, shown more than qualitative and quantitative data collection in various restricted areas. This is due to the extensive and complicated chain of reactions on the surface of sediments and in the sediment itself. Biologists are asking for the amount of organic and inorganic matter which is reworked and released to the sea. Geologists usually emphasize the amount of substances which are sedimentated. For biologists the sediment is only part of their dominant ecosystem (the sea). While, for geologists the “sea” is only furnishing and influencing their first range system sediment. How much then, are bacteria involved in the slow process of conversion from a recent sediment to sedimentary rocks? Bacteria influence more or less strongly and to a more or less advanced degree of diagenesis:
- The organic matter in sediments and the final form in which it is found.
- The anions CO3 2?, NO3 ?, OH-, SO4 2?, PO4 3? as well as their intermediate stages and the resulting minerals.
- The cations H+, NH4 +, Ca2+, Fe2+, Fe3+, and a series of metals which are dissolved or precipitated by microbial activities as for example Fe, Mn, Cu, Ag, V, Co, Mo, Ni, U, Se, Zn.
- The equilibrium of silicium. At least diatoms and radiolarians are precipitating silica, while other reactions which have been proved are not yet shown to influence marine sediments.
- pH-values and oxidation-reduction potentials of the sediment.
- The composition of interstitial waters.
- The surface activity of minerals, since bacteria are growing especially on particle surfaces.
- The energy content and temperature of sediments.
- The texture of fine grained sediments.
- The fossilization of microfauna, macrofauna and trace fossils.
16.
《Organic Geochemistry》1987,11(5):371-377
Fluorescence microscopy is useful not only for identifying most of the oil-prone organic matter (macerals) in sedimentary rocks and coals but also for assessing their thermal maturities (ranks). This report introduces a violet-light excitation system which induces more than one order of magnitude stronger fluorescence intensity that the commonly used UV-light excitation system. The red/green quotient from violet-light excited fluorescence, Qv, of sporinite can be easily measured using this system. Several examples using coal and cuttings samples are presented to demonstrate the use of this technique for evaluating the thermal maturities of coals and sedimentary rocks.From the results of our studies we conclude that:
- 1.(1) Violet-light excited fluorescence from sporinites can be routinely measured to assess thermal maturity.
- 2.(2) Spectral (Quantitative) fluorescence technique is useful for evaluating thermal maturity when samples are poorly polished or deficient in vitrinite.
- 3.(3) Visual (Strew-mounted) kerogen slides can not be used for fluorescence measurements unless a non-fluorescent mounting medium is used.
17.
《Applied Geochemistry》1991,6(4):435-445
The36Cl/Cl ratios of 12 groundwater samples from the Milk River aquifer were determined by accelerator mass spectrometry. Using known Cl concentrations,36Cl concentrations were deduced. Approximately linear relations were observed between the logarithm of the36Cl concentration, the Cl concentration, and the distance from the recharge area along two flow paths. The results are discussed in two approaches:
- (1)in an interpretation of the linear relation between logarithm of the36Cl concentration and Cl concentration excluding and includingin situ production of36Cl;
- (2)in a diffusion model. The increase of the Cl concentration with the distance from the recharge area is considered to be due to diffusion of Cl from the underlying confining Colorado shale to the aquifer.
18.
This paper discusses the history and application of in situ recovery (ISR) to a wide variety of metals. The increasing application of ISR may provide an important method to address a key issue for the mining industry, namely the cost of production.ISR transfers a significant proportion of hydrometallurgical processing to mineralised bodies in the subsurface to directly obtain solutions of metals of interest. As a result, there is little surface disturbance and no tailings or waste rock are generated at ISR mines. However, for ISR to be successful, deposits need to be permeable (either naturally or artificially induced), and the metals of interest readily amenable to dissolution by leaching solutions in a reasonable period of time, with an acceptable consumption of leaching reagents.The paper discusses the following aspects of ISR:
- •History. ISR for uranium was introduced in 1959 in the USA, and subsequently applied in many countries over last 50 years, particularly in the USSR. The share of uranium mined by ISR reached 51% of world production in 2014, and the capacity of ISR mining of uranium is now comparable with that from conventional uranium mines.
- •Commodities. A review of the use of ISR for mining other commodities, namely copper, gold, nickel, scandium, rhenium, rare earth elements, yttrium, selenium, molybdenum, and vanadium. ISR for copper was introduced in the 1970s and there were several successful natural tests and mines. Scandium, rhenium, rare earth elements, yttrium, selenium, molybdenum, and vanadium were mined in pilot tests as by-products of uranium extraction. ISR of gold, copper, nickel, rare earth elements and scandium has been successfully developed over recent years. The paper discusses other commodities that have potential to be mined using ISR.
- •Applicability of ISR is addressed by a discussion of the features of mineralisation that need to be considered during different stages of ISR projects. Permeability,1 hydrogeological conditions and selective leachability are the most critical parameters for ISR, and must be defined in the evaluation and exploration stages. Morphology and depth of mineralisation, thicknesses and grades, distribution of mineralisation, presence of aquicludes, and environmental conditions are also important factors for ISR projects.
- •Environmental issues. ISR allows the extraction of mineralisation with minimal disturbance to existing natural conditions. In contrast to underground and open pit mining, there are smaller volumes of mining and hydrometallurgical effluents that require management. Clearly contamination of groundwater by ISR reagents is the critical aspect requiring management during an ISR operation. Control of leaching in ISR operations and various ways of cleaning aquifers are discussed in the paper.
- •Economics. ISR operations deliver a range of benefits including lower CapEx costs for mine development, processing plant and infrastructure. ISR enables production to start at low capital cost and then a modular increase in production, as well as very flexible production capacity. The costs of ISR for different commodities (copper, gold, nickel, scandium, rhenium, rare earth elements, yttrium, selenium, molybdenum, vanadium) are discussed, with economic parameters for uranium production from ISR and conventional provided for comparison. The CapEx, OpEx and common cut-off grades for ISR for different commodities are discussed.
- •Exploration, resource estimation and the development of ISR projects require a number of different approaches compared to conventional mining projects. These criteria and the necessary methodology for resource estimation for ISR projects are described in the article.
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20.
《Tectonophysics》1987,132(4):311-320
A Bayesian discrete distribution, as developed by Ferraes (1985), is applied to predict the inter-arrival times for strong shocks in the Hellenic Arc on the basis of nine samples of shocks with seismotectonic locations very different from those used by Ferraes. The results suggest an alternative view of the Bayesian probabilistic prediction of strong earthquakes in the Hellenic Arc, and can be summed up as follows:
- 1.(a) Maximum final Bayesian probabilities of various inter-arrival times in a given seismotectonic segment are very dependent on the data set used and particularly on its time length.
- 2.(b) When using this method to determine the time intervals during which large shocks are to be expected in the Western and Eastern Hellenic arcs, it is very difficult to estimate intervals of less than a decade. The determination of the occurrence time, even in the long-term sense, remains the major problem in the prediction of these shocks.
- 3.(c) Bayesian probabilities in conjunction with seismicity observations indicate that large intermediate depth earthquakes in the Hellenic Arc are long overdue. Shocks of this sort can be expected to occur in the next few years.