铀在近代海洋生物中的积聚     

Saday Azadoglu ALIYEV  Ali SARI 《地质学报》2003,77(3)

本文研究的目的是确定软体动物对于铀在海洋生态系统中的分布所起的地球化学作用。对取自里海、日本海、马尔马拉海、爱琴海、黑海、地中海、波罗的海和印度洋的近代软体动物贝壳进行了生物地球化学研究,这些贝壳的物理、化学、地理和地球化学特征各不相同。本次研究中,分析了9个腹足类和54个双壳类不同种的贝壳以记录铀在不同季节层中的变化。季节层是由软体动物在整个生命过程中季节性的碳酸盐—有机相生成的。研究中使用的贝壳主要分3层:上(外)棱柱层,中棱柱层,内(珠母)层。此外,条件许可时,将贝壳性的头部、中部和下部分别进行分析,并且还计算出相对  相似文献   

Cenozoic Plate interaction of the Australia and Philippine Sea Plates: “hit-and-run” tectonics     

Manuel Pubellier  Jason Ali  Christophe Monnier 《Tectonophysics》2003,363(3-4):181-199

Recent studies in northwest New Guinea have shown the presence of at least two marginal basins of different age, both of which formed in back-arc settings. The older basin opened between the Middle Jurassic and Early Cretaceous, a remnant of which is now preserved as the New Guinea Ophiolite. Its obduction started at 40 Ma and it was finally emplaced on the Australian margin at 30 Ma. The younger basin was active during the Oligocene to Middle Miocene and was obducted in the Early Pliocene. Studies of the western edge of the Philippine Sea also reveal an important deformation of the Philippine arc in the Oligocene, which hitherto has remained unexplained. Using information from these systems, paleomagnetic results, kinematic reconstructions and geochemistry of the supra-subduction ophiolite, we present a plate model to explain the region's Eo–Oligocene development. We suggest that an extensive portion of oceanic crust extended the Australian Plate a considerable distance north of the Australian Craton. As Australia began its steady 7–8 cm/year northward drift in the Early Eocene, this lithosphere was subducted. Thus, the portion of the Philippine Sea Plate carrying the Taiwan–Philippine Arc to its present site may have actually been in contact with the ophiolite now in New Guinea and obduction led to deformation of the Philippine Sea Plate itself. Neogene Plate kinematics transported the deformed belt in contact with the Sunda block in the Late Miocene and Pliocene. This interpretation has implications for the origin for the Philippine Sea Plate and the potential incorporation of continental fragments against its boundaries.  相似文献   

Origin and Formational Environment of Noda-Tamagawa Manganese Ore, Northeast Japan: Constraints from Isotopic Studies     

Mohammed El Rhazi  Ken-ichiro Hayashi 《Chemie der Erde / Geochemistry》2003,63(2):149-162

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Analysis of parameters of ground vibration produced from bench blasting at a limestone quarry     

Ali Kahriman 《Soil Dynamics and Earthquake Engineering》2004,24(11):887-892

The aim of this study is to predict peak particle velocity level at a limestone quarry located in Istanbul, Turkey. The ground vibration components were measured for 73 blast events during the bench blast optimization studies during a long period. In blasting operations; ANFO (blasting agent), gelatine dynamite (priming) and NONEL detonators (firing) were used as explosives at this site. Parameters of scaled distance (charge quantity per delay and the distance between the source and the station) were recorded carefully and the ground vibration components were measured by means of vibration monitors for every event. Then, the data pairs of scaled distance and particle velocity were analyzed. The equation of scaled distance extensively used in the literature was taken into consideration for the prediction of peak particle velocity. At the end of statistical evaluations, an empirical relationship with good correlation was established between peak particle velocity and scale distance for this site. The established relationship and the results of the study are presented.  相似文献   

Effect of salinity on chlorophyll concentration, leaf area, yield and yield components of rice genotypes grown under saline environment     

Y. Ali  Z. Aslam  M. Y. Ashraf  G. R. Tahir 《International Journal of Environmental Science and Technology》2004,1(3):221-225

Salt tolerance in eighteen advanced rice genotypes was studied under an artificially salinized (EC=8.5 dSm^?1) soil conditions after 90 days of transplanting. The results showed that the yield per plant, chlorophyll concentrations, fertility percentage, and number of productive tillers, panicle length and number of primary braches per panicle of all the genotypes were reduced by salinity. However, genotypes viz. Jhona-349 x Basmati-370, NR-1, DM-59418, DM-63275, DM-64198 and DM-38-88 showed better salinity tolerance than others.  相似文献   

Economic analysis for the production of four grape cultivars using microcatchment water harvesting systems in Iran     

Hamid Reza Fooladmand  Ali Reza Sepaskhah   《Journal of Arid Environments》2004,58(4):478

An economic analysis was conducted for temporal yield variations of four local grape cultivars grown in rain-fed microcatchments in the Bajgah area of Fars province, in Islamic Republic of Iran. For this study, four local cultivars of grapes were considered. The cultivars examined were Black Rishbaba, Rotabi, Asgari and Black grapes. The soil type was a gravely loam with an average slope of 5–6%, in microcatchment systems, and in plots without microcatchments. Analysis of yield data with a multiple regression model indicated that a 9 m² (3×3 m) microcatchment area for each individual plant (vine) was the most appropriate area for vineyards in this region. The results also demonstrated that by using this area for each grapevine, yields (kg/ha) were 40% greater than yields obtained for vines in the standard vineyard (without microcatchments) in this area. Economic analysis was performed and the cost and income were compared for a depreciation period (life-span period) of 50 years and interest rate of 14%. The analysis showed that a microcatchment area of 9 m² is economically feasible. The Black Rishbaba rain-fed vines were the most suitable cultivar for this region. The benefit probabilities of rain-fed Black Rishbaba, Rotabi, Asgari and Black grapes with a microcatchment area of 9 m² and without such an area were 63.3% (i.e. two of 3 years), 52.4% (i.e. one of 2 years), 32.9% (i.e. one of 3 years), 13.3% (i.e. one of 8 years), and 59.5% (i.e. two of 3 years), 39.4% (i.e. two of 5 years), 31.8% (i.e. one of 3 years), and 10.7% (i.e. one of 9 years), respectively. Therefore, the Black Rishbaba and Rotabi cultivars are economically more stable in microcatchment system, while only the Black Rishbaba cultivar would be such in the standard vineyard system.  相似文献   

Curie-point depth map of Turkey   总被引：3，自引：0，他引：3  

&#;brahim Ayd&#;n  Halil &#;. Karat  Ali Koçak 《Geophysical Journal International》2005,162(2):633-640

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The Okavango giant mafic dyke swarm (NE Botswana): its structural significance within the Karoo Large Igneous Province   总被引：1，自引：0，他引：1  

Bernard Le Gall  Gomotsang Tshoso  Jrme Dyment  Ali Basira Kampunzu  Fred Jourdan  Gilbert Fraud  Herv Bertrand  Charly Aubourg  William Vtel 《Journal of Structural Geology》2005,27(12):783

The structural organization of a giant mafic dyke swarm, the Okavango complex, in the northern Karoo Large Igneous Province (LIP) of NE Botswana is detailed. This N110°E-oriented dyke swarm extends for 1500 km with a maximum width of 100 km through Archaean basement terranes and Permo-Jurassic sedimentary sequences. The cornerstone of the study is the quantitative analysis of N>170 (exposed) and N>420 (detected by ground magnetics) dykes evidenced on a ca. 80-km-long section lying in crystalline host-rocks, at high-angle to the densest zone of the swarm (Shashe area). Individual dykes are generally sub-vertical and parallel to the entire swarm. Statistical analysis of width data indicates anomalous dyke frequency (few data <5.0 m) and mean dyke thickness (high value of 17 m) with respect to values classically obtained from other giant swarms. Variations of mean dyke thicknesses from 17 (N110°E swarm) to 27 m (adjoining and coeval N70°E giant swarm) are assigned to the conditions hosting fracture networks dilated as either shear or pure extensional structures, respectively, in response to an inferred NNW–SSE extension. Both fracture patterns are regarded as inherited brittle basement fabrics associated with a previous (Proterozoic) dyking event. The Okavango N110°E dyke swarm is thus a polyphase intrusive system in which total dilation caused by Karoo dykes (estimated frequency of 87%) is 12.2% (6315 m of cumulative dyke width) throughout the 52-km-long projected Shashe section. Assuming that Karoo mafic dyke swarms in NE Botswana follow inherited Proterozoic fractures, as similarly applied for most of the nearly synchronous giant dyke complexes converging towards the Nuanetsi area, leads us to consider that the resulting triple junction-like dyke/fracture pattern is not a definitive proof for a deep mantle plume in the Karoo LIP.  相似文献   

Use of environmental friendly fertilizers in saline and saline sodic soils     

Y. Ali  Z. Aslam 《International Journal of Environmental Science and Technology》2005,2(1):97-98

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Assessment of contaminants in Dubai coastal region, United Arab Emirates     

H. A. Al-Darwish  E. A. Abd El-Gawad  F. H. Mohammed  M. M. Lotfy 《Environmental Geology》2005,49(2):240-250

Coastal uses and other human activities have inevitably impinged on the Gulf environment; therefore, these regions require continuous monitoring. The investigated area covered the maximum fragments of Dubai coastal region in the Arabian Gulf. The determination of major oxides and trace metal concentrations in Dubai sediments revealed three heavily and moderately contaminated regions. One is in the far northeastern part at Al-Hamriya Sts 1–3 and contaminated by Fe, Cu, Pb, and Zn; the second is in the mid-northeastern part at Dry Docks and contaminated by Cu, Ni, Pb, and Zn; and finally, the third is in the near southwestern part at Dubal and contaminated by Fe, Mg, Cr, Ni, and Zn. Al-Hamriya St 3 represented the highest values of Cu, Pb, and Zn, whereas Dubal exhibited the maximum values of Fe, Mg, Ba, Cr, Mn, Ni, and V. The anthropogenic discharge and natural deposits are the main sources of contamination. In general, all trace and major elements showed the minimal levels at Jebel Ali Sanctuary (Sts 11, 12, 13) except for Sr and Ca, which showed their maximum values. The highest concentrations of Ca and Sr are mainly attributed to carbonate gravel sands and sands, which cover most stations. Each of V and Ni showed negative correlation with TPH, which may be indicated that the source of oil contamination in the region is not related to crude oil but mostly attributable to anthropogenic sources. The significant positive correlation, which was found between trace metals and TOC indicates that organic matter plays an important role in the accumulation of trace metals in case of Cu, Zn, and Pb.  相似文献