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991.
Anisotropy of magnetic susceptibility (AMS) is investigated in samples of Peralimala (PM) pluton (ca. 550 Ma) and adjacent gneiss, gabbro, mylonite and amphibolite from the Moyar Shear Zone (MSZ), Southern Granulite Terrane (SGT) with an aim to decipher the time-relationship between fabric development in the pluton and regional tectonics. Magnetic foliation recorded in the PM pluton is sub-parallel to the WNW-ESE striking MSZ. Magnetic foliation and lineation trajectories are sigmoidal and curve into the shear zone. A dextral sense of shear is deciphered from the trajectories, which is similar to that reported within the MSZ in some earlier studies. It is inferred that the PM pluton has developed post-emplacement deformation-fabric related to reactivation of the MSZ during Pan-African age. Based on the data and existing information about regional tectonics of the area, the possibility of the (a) PM pluton being a Deformed Alkali Rock and Carbonatite (DARC) and (b) MSZ marking an ancient suture zone, is discussed.  相似文献   
992.
John Finn 《GeoJournal》2009,74(3):191-200
After more than three decades of isolation from the West and a paralyzing economic crisis in the early 1990s, Cuba is increasingly globally active in both cultural and economic realms. In this paper I use Bourdieu’s (The fields of cultural production, 1993) fields of cultural production as a general frame through with to inspect the commercialization of Cuban music. Through a case study with Juan de Marcos Gonzalez, the creator of the Buena Vista Social Club, I explore the dialectical relationship of music as an expression of cultural and a cultural asset, and at the same time a commodity for the international market. I show that de Marcos uses his position between the international music industry and the local music scene in order to preserve cultural authenticity and survive economically. In doing so he challenges the all-to-typical place of the artist in the contested space of cultural production between the West and the Third World.
John FinnEmail:
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993.
Agricultural practices, hydrology, and water quality of the 267-km2 Big Spring groundwater drainage basin in Clayton County, Iowa, have been monitored since 1981. Land use is agricultural; nitrate-nitrogen (-N) and herbicides are the resulting contaminants in groundwater and surface water. Ordovician Galena Group carbonate rocks comprise the main aquifer in the basin. Recharge to this karstic aquifer is by infiltration, augmented by sinkhole-captured runoff. Groundwater is discharged at Big Spring, where quantity and quality of the discharge are monitored. Monitoring has shown a threefold increase in groundwater nitrate-N concentrations from the 1960s to the early 1980s. The nitrate-N discharged from the basin typically is equivalent to over one-third of the nitrogen fertilizer applied, with larger losses during wetter years. Atrazine is present in groundwater all year; however, contaminant concentrations in the groundwater respond directly to recharge events, and unique chemical signatures of infiltration versus runoff recharge are detectable in the discharge from Big Spring. Education and demonstration efforts have reduced nitrogen fertilizer application rates by one-third since 1981. Relating declines in nitrate and pesticide concentrations to inputs of nitrogen fertilizer and pesticides at Big Spring is problematic. Annual recharge has varied five-fold during monitoring, overshadowing any water-quality improvements resulting from incrementally decreased inputs. Electronic Publication  相似文献   
994.
The paper deals with the processes of ethnic consolidation, ethnic and linguistic assimilation and inter-ethnic integration taking place in the USSR. The author shows the influence of consolidation and assimilation processes over the trends in the numerical strength of individual peoples and the resulting change in the country's ethnic composition as this is reflected in the Soviet population censuses of 1926, 1959, 1970, and 1979.  相似文献   
995.
From the studies of ore deposit geologic settings,sulfur isotopes,lead isotopes,carbon isotopes and oxygen isotopes,fluid inclusions and petrochemistry in this paper,the authors have drawn a conclusion that the ore-forming hydrothermal solutions are the high-temperature magmatic hydrothermal solutions for the gold ore deposit,and at the same time,the involvemety of crustal materials can not be ruled out .It is the first time that the authors have proposed that the Laozuoshan gold-ploymetallic ore deposit in Heilongjiang Province was formed in the calc-alkaline series environment at the margin of an active continent.  相似文献   
996.
1IntroductionLanmuchangite ,anewmineralTlAl[SO4]2 ·1 2H2 O ,occursintheoxidationzoneofrichthalli umorebodiesattheLanmuchangthallium(mercury)deposit.Itisnamedafterthelocalitywhereitwasdiscovered .InJune,2 0 0 1 ,themineralanditsnamewereapprovedbytheCommissiononNewMineralsandMineralNames,IMA .ItstypicalmaterialisdepositedattheGeologicalMuseumofChina ,Beijing .2OccurrenceandmineralassociationLanmuchangiteoccursintheoxidationzoneofrichthalliumorebodiesattheLanmuchangthal lium(mercury)or…  相似文献   
997.
Measured settlements of buildings on the weathered Keuper Marl appeared to be much smaller than calculated settlements, which were based on stiffness modulus from standard oedometer tests. Therefore, both special triaxial K 0-tests and oedometer tests were carried out for an accurate determination of stiffness moduli. Modulus obtained in the triaxial K 0-tests were at least two to three times the values obtained in the oedometer tests. To verify observations from the laboratory tests, the loads and the settlements of two single footings on weathered Keuper mudstone have been measured during construction of a building over 1 year. Also, a large scale footing load test with measurements of deformations were conducted on the weathered Keuper mudstone. The measured settlements of the two single footings and the tested foundation were compared with the settlements based on conventional calculations with moduli from oedometer tests and triaxial K 0-tests. Up to a foundation pressure of σv = 500 kN/m2 the calculated settlement based on E S-modulus obtained from triaxial K 0-tests was found to correspond well to the measured deformation. For foundation pressure beyond 500 kN/m2, the foundation response was highly non-linear and it could not be described any more with the linear-elastic model. Therefore the footing load test was also simulated by FEM analyses.  相似文献   
998.
A total of 42 samples of road dust were collected along ring road, city centre, city side, and freeway in Urumqi, China. Total concentrations of Cd, Cr, Cu, Ni, Pb, Mn, Be, Co, Zn, and U were determined by using the inductively coupled plasma-mass spectrometry in order to assess and to compare road dust contamination levels of metals among the four roads. The results show that, among the four categories of roads, mean concentrations of Co and U vary little. City centre locations show strong enrichments of Cd, Cu, Pb, and Be. Along the ring road, the highest mean concentrations were found for Cr, Ni, Mn, and Co. However, the highest concentrations of Zn and U were found along the freeway. The cluster analysis shows that three main groups can be distinguished. Every group may be associated with different main sources and concentrations of the metals. The results of contamination assessment reveal that, among all of the potential toxic metals, Cd, Cu, and Zn pollution were obviously heavier with moderate or high contamination indices for most road dust samples, while Cr, Ni, and Pb contamination were lower along the four categories of roads. Compared with the city side, Cd, Cu, Pb, Ni, and Zn contamination were heavier along the ring road, the city centre, and the freeway with high traffic density. Low Pb contamination or no contamination in all the road dust samples may be related to the increasing usage of lead-free petrol.  相似文献   
999.
Quantitative vulnerability estimation for scenario-based landslide hazards   总被引:3,自引:1,他引:3  
Within the engineering profession and natural sciences, vulnerability is widely accepted to be defined as the degree of loss (or damage) to a given element or set of elements within the area affected by a threat. The value of vulnerability is expressed nondimensionally between 0 and 1. It is a fundamental component in the evaluation of landslide risk, and its accurate estimation is essential in making a reasonable prediction of the landslide consequences. Obviously, vulnerability to landslides depends not only on the characteristics of the element(s) at risk but also on the landslide intensity. This paper summarizes previous research on vulnerability to landslides and proposes a new quantitative model for vulnerability of structures and persons based on landslide intensity and resistance of exposed elements. In addition, an approximate function is suggested for estimating the vulnerability of persons in structures. Different methods for estimating the vulnerability of various elements to slow or rapid landslides are discussed. Finally, the application of the new model is illustrated through an example.  相似文献   
1000.
The native riparian herbs such as Leonotis nepetaefolia (L.) R. Br., Cassia tora L., Ageratum conyzoides L., Parthenium hysterophorus L. and Sida acuta burm f., dominant on the bank of River Damodar in Eastern Jharia Area, Dhanbad (India), were selected to assess experimentally their quantitative role in conserving the soil and reducing water runoff and nutrient (N and P) losses. A total of 42.5 mm simulated rainfall were applied at 30 cm h−1 rain intensity on both vegetated and bare plots. The collected runoff water and eroded soil from each plot were determined in terms of soil, water and nutrient conservation value (CV). Among the vegetated plots, soil CV ranged from 30 to 85% and water CV from 20 to 48%. Nutrient (N and P) CV varied from 22 to 65% for total-N, 48 to 80% for ammonia-N and 50 to 86% for nitrate-N. CV for total-P varied from 40 to 62%, inorganic-P from 42 to 60% and organic-P from 20 to 58%. In a stepwise multiple regression equation comprising four independent variables (canopy cover, litter mass, soil moisture and plant biomass), canopy cover explained 70–88% (P < 0.01) of variability in conserving soil, water and nutrient. The losses through runoff water and eroded soil from vegetated plots were found to be minimized to a great extent as compared to bare plots. The role of these species in maintaining the texture and fertility status of riparian soil is discussed.  相似文献   
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