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1.
The complex study of the river water and pore solutions from the bottom sediments in the lower reaches of the Razdol’naya River was conducted in February 2010. The major ion composition of the waters indicates the submarine origin of the near-bottom and pore waters in the lower reaches of the Razdol’naya River in the winter. The river estuary extends upstream for more than 20 km. It was established that the studied sediments are reduced oozes containing pyrite, hydrotroilite, and iron monosulfide, which is direct evidence for sulfate-reduction in the sediments. The diagenesis of organic matter is the main reason for the considerable decrease in the amount of sulfates and the increase in the alkalinity of the sediment pore water. The sedimentary pore water sampled from the deep river pits is characterized by excess alkalinity that cannot be explained by sulfate-reduction and methane genesis. It was suggested that the chemical weathering of silicate minerals and the bacterial mineralization of salts of organic acids could result in the excess alkalinity of the sediment pore water.  相似文献   

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Taking into consideration additional data indicating the reorientation of the Razdol’naya River flow in the Pleistocene, a new model of its capture is proposed. The latter is based on the principle of the more aggressive behavior of rivers draining the eastern megaslope of the Sikhote Alin mountainous system, including the river that captured the Razdol’naya River flow.  相似文献   

4.
Palynological samples, plant megafossils, and fossil wood taken from the upper Lipovtsy Subformation (Porechye open-pit coal mine in the Il’ichevka coalfield, Razdol’naya River Basin, southern Primorye), as well as coal samples for determining coal-forming plants from dispersed cuticles are analyzed. The taxonomic composition of the identified palynomorphs from the coals and interstratal clastic sediments indicates the Aptian age of host deposits. The palynological spectra from the lower humic–rhabdopissite coal seam are dominated by Gleicheniaceae and Cyatheaceae accompanied by Dicksoniaceae and Ginkgocycadophytus. In the palynological spectra from the upper coal seam, the share of Gleicheniaceae substantially decreases, though they remain dominant; simultaneously, single angiosperm pollen grains appear in them. The spectra from the clastic rocks are dominated by Polypodiaceae and Cyatheaceae. The taxonomical composition of the gymnosperms is relatively diverse, although their abundance is low. The share of angiosperms increases with respect to both their diversity and abundance. The angiosperm pollen, found for the first time in the Aptian deposits of the Razdol’naya River Basin, provides grounds to assume that these pants appeared earlier than previously thought (early Albian). The coal-forming plants of the Il’ichevka coalfield are determined.  相似文献   

5.
The composition of clay minerals in the subcolloid fraction from the uppermost layer of bottom sediments in the northern part of Amur Bay was determined by X-ray powder diffraction analysis, and the enrichment of 33 elements in the subcolloid and pelite fractions of the surface deposits from a number of sites at the marginal filter of the Razdol’naya River was studied by ICP-MS.Fe, U, and chalcophile elements are contained in the highest concentrations in sediments from all sampling sites within the filter. The bottom sediments are not enriched in trace, alkali, and alkali-earth elements. The maximum concentrations of chemical elements were found in deposits from the brackish part of the marginal filter, perhaps, because of the formation of Fe and Mn (Al) hydroxides. Bottom sediment at the boundary between the brackish and marine parts of the filter contain the lowest concentrations of the examined elements.  相似文献   

6.
Original isotopic and chemical data are reported on the groundwater and gases from the unique occurrence of mineral water in the coastal zone of southern Primorye. Results of the δ18O and δ2H analysis of the underground and surface water of the area integrated with their δ13C composition made it possible to solve the problem of the genesis and evolution of groundwater and gases in the coastal part of the Sea of Japan. It was established that meteoric waters penetrate into the Mesozoic terrigenous rocks and changed their chemical composition under the influence of transformation of organic matter from the host rocks. CO2 released owing to reactions provides multiple enrichment of the water in HCO3 and stimulates Na influx via dissolution of aluminosilicates.  相似文献   

7.
Based on the analytical results for 101 samples from 50 survey spots,this paper describes the changes in rations of various components in calcium carbonate from the sea area at the Pearl River mouth with pH.Relations of ∑CO2 with salinity,and Ca concentration with salinity in different parts of the river mouth have been established.The annual throughput of Ca from the Pearl River and the saturation degrees of calcite and aragonite have been calculated.  相似文献   

8.
Water resources system is composed of natural water subsystem and social water subsystem. And it is a complicated large system, which contains certain regional background, as well as specific framework, function and dynamic balance. The evaluation of the water resources system needs the viewpoint of sustainable development and the measurement according to water resources system carrying capacity, which holds the meaning of both water resources carrying capacity and water environment carrying capacity. The Changjiang River Delta is a very important area in China. As the local water resources are concerned, the Delta is an area lack of water as a matter of fact. The water resources system of the Delta experiences a long, intricate and degenerate period. The lack of water due to resources shortage in the 1950's was converted to that due to water quality from the 1980's. Furthermore, the status of water shortage sharpens gradually. The representations are summarized as follows: firstly, the discharge amount of wastewater and polluted water is large all along. Secondly, the pollution status of rivers, which involve the Changjiang River, the Grand Canal, the rivers in cities and the rivers in small towns and villages, is noticeable. Thirdly, water quality of Taihu Lake is worth of more attention. Therefore, the countermeasures on the reconditioning and regulating of water resources system in the Delta demands the following new strategies, such as to treat the rivers, the lakes and the seas as one overall system, to improve, harmonize and counterpoise water resources system carrying capacity, to implement the integrated management of water resources, which means the integrated management of drainage area along with the regional area, especially the integrated management of city water, and to carry on water saving and scientific use so as to increase the efficiency of water use, and so on.  相似文献   

9.
The Qilian Mountains water conservation forest in Gansu province is an important ecological barrier surrounding the oasis in China’s Hexi Corridor. The water they provide is the basis for the existence and sustainable socioeconomic development of those oases. As a result of unsustainable use of the water conservation forest until the 1980s, the oasis ecosystems of the Hexi region were seriously damaged, and the oasis areas experienced deterioration of their ecological environment. In this paper, Landsat images were used to monitor the temporal and spatial changes in area of water conservation in Qilian Mountains of China’s Gansu province and to assess the effect on water conservation by analyzed relationship between water conservation forest area, climatic data and hydrological data. The results showed that the forest covered 15.1% of the study area in 2007 and has followed different trends during the study period. From 1978 to 1990, the forest area decreased; however, from 1990 to 2007, the forest area increased, with a faster rate of increase from 1990 to 2000, and the rate of increase averaged 2,733.89 ha per year since 1990. The water conservation forest appears to play an important role in flood control, runoff regulation, the prevention of soil erosion, and water conservation; and these benefits increase with an increasing area of forest.  相似文献   

10.
The study of hydrochemical models and probable pollution in Euphrates River from Qaem–Al-Falluja was performed through regime observation in ten water points. The hydrochemical properties of Euphrates River waters are determined by using the analysis results of 21 physico-chemical variables during the water year (2008). The interpretation of the hydrochemical phenomena is achieved in accordance with the statistical results of Polynomial Regression Statistic, calculating the coefficient of variation among the physico-chemical components of the water terminating by 14 models. The results of monitoring during the water year 2008 indicate a pollution case by SO4 and Cd in Ramadi and downstream stations; TDS, Mg, Na, Cl, Mn, and CO2 in Ramadi station; TDS, Ca, Na, Cl, and Fe in Baghdadi station; and Ca and H T in Qaem station and Mg in Obaydi station. The research suggests the best locations for hydrochemical monitoring as continuous hydrologic stations used for the long-term monitoring. These stations are in Qaem city as inlet location and Al-Baghdadi and Ramadi cities terminating in Falluja city as outlet location. Furthermore, daily record system is recommended for the other stations in each city to complete the regime observation of Euphrates water type. From the configuration approach of hydrochemical models with the pollution phenomena, there are potential point sources of pollution such as municipal effluent pipes and reused water from mining process for building materials in the first sector of river, which extends between Qaem and Haditha dam. Also groundwater seepages and springs discharge of mineralized water mixed with sewage water from cities act as potential point sources of pollution on the river water in the second sector extended between Haditha and Ramadi scheme. The third sector of the river is affected by all reasons in the first and second sectors as well as the effectiveness of agricultural activities throughout drainage canals and irrigation projects extended between Ramadi and Falluja cities.  相似文献   

11.
The results of bio- and lithostratigraphic studies of the Givetian-Frasnian rocks in the Tsil’ma River basin are reported. They suggest regularities in sedimentation: distinct rhythmicity and similar succession in the structure of formations. We have identified five palynocomplexes that characterize the formations and make it possible to accomplish a confident biostratigraphic subdivision of sections. Their correlation with coeval complexes in the adjacent areas has been accomplished. The results made it possible to unravel specific features of miospore assemblages formed in the continental and coastal-marine facies.  相似文献   

12.
The Daning River is a very important tributary in the Three Gorges Reservoir area. It is also a famous scenic spot. Anomalies appeared after water storage of the reservoir in June, 2003. In September, 2003, eutrophication monitoring in the 135-m backwater reach of the Daning River was conducted and the data were simply analyzed. The assessment result is that water body in the segment from Shuauglong to Longmen was mesotrophic or eutrophic. At the same time, the causes of its nutritional change were discussed, and counter-measures have been proposed.  相似文献   

13.
The analysis of radiolarian assemblages and lithological types of siliceous rocks yielded new data on the structure of different sequences constituting the northern Algan terrane in the Pereval’naya River basin. Three tectonic slices formed by different lithothectonic complexes can be defined in this area. The radiolarian assemblages from the volcanogenic-siliceous slice allow the oceanic section to be dated back to the Kimmeridgian-Valanginian. The tuffaceous-terrigenous slice contains cherts of two types: (1) formed in situ and (2) reworked. The reworked deep-sea cherts yielded Bathonian-Kimmerdgian and Bathonian-Oxfordian radiolarians, while late Aalenian-late Bathonian radiolarian assemblages were extracted from the Kimmerdgian-Tithonian matrix of siliceous rocks.  相似文献   

14.
Wadsleyite II is a variably hydrous magnesium-iron silicate phase similar to spinelloid IV and a potential host for H in the Transition Zone of the Earths mantle. Two separate samples of wadsleyite II synthesized at 17.5 GPa and 1400°C and at 18 GPa and 1350°C have been characterized by electron microprobe, single-crystal X-ray diffraction, visible, IR, Raman, and Mössbauer spectroscopies, and transmission electron microscopy including electron energy-loss spectroscopy. The two samples have the following chemical formulae: Mg1.71Fe0.18Al0.01H0.33Si0.96O4 and Mg1.60Fe0.22Al0.01 H0.44Si0.97O4. Mössbauer spectroscopy and electron energy loss spectroscopy (EELS) indicate that about half of the iron present is ferric. Refinement of the structures shows them to be essentially the same as spinelloid IV. Calculated X-ray powder diffraction patterns show only subtle differences between wadsleyite and wadsleyite II. The hydration mechanism appears to be protonation of the non-silicate oxygen (O2) and possibly the oxygens surrounding the partially vacant tetrahedral site Si2, charge-balanced by cation vacancies in Si2, M5 and M6. The unit cell volume of this phase and its synthesis conditions indicate that it may be an intermediate phase occurring between the fields of wadsleyite and ringwoodite, if sufficient trivalent cations are available. The unit cell parameters have been refined at pressures up to 10.6 GPa by single-crystal X-ray diffraction in the diamond anvil cell. The refined bulk modulus for the sample containing 2.8 wt% H2O is 145.6 ± 2.8 GPa with a K of 6.1 ± 0.7. Similar to wadsleyite and ringwoodite, hydration has a large effect on the bulk modulus. The presence of this phase in the mantle could serve to obscure the seismic expression of the phase boundary between wadsleyite and ringwoodite near 525 km. The large apparent effect of hydration on bulk modulus is consistent with hydration having a larger effect on seismic velocities than temperature in the Transition Zone.  相似文献   

15.
The Paleogene–Neogene stratigraphic scale of the Zerkal’naya River basin is modified with account for new isotopic and paleobotanical data. It is established that the Tadushi Formation and underlying volcanics, which were previously considered as representing transitional Cretaceous–Paleocene strata, are separated in the section of the Ustinovka quarry by a significant stratigraphic hiatus. According to the new data, the volcanics and the Tadushi Formation are established as Campanian and Late Paleocene in age, respectively. The Bogopol Formation in the type section is dated back to the Middle–Late Paleocene. The Svetlyi Formation is now considered to be Early Eocene in age, rather than Late Eocene–Oligocene as previously thought. A new variant of the stratigraphic scale is proposed for the Paleogene–Neogene deposits of the Zerkal’naya depression.  相似文献   

16.
Jian  Wei  Liang  Dongfang  Shao  Songdong  Chen  Ridong  Liu  Xingnian 《Natural Hazards》2015,78(1):531-553
Natural Hazards - The mixing process of upstream and downstream waters in the dam break flow could generate significant ecological impact on the downstream reaches and influence the environmental...  相似文献   

17.
Under the tectonodynamic process, crustal materials tend to experience two modes of adjustment: (1) structural (physical) adjustment, manifested by folding, faulting, uplifting, downwarping, etc.: (2) compositional adjustment, represented by element migration, concentration and dispersion, crystalline and dynamic differentiation of crystals, metamorphism, etc. (Yang Kaiqing. 1986; Yang Kaiqing et al., 1986). The dynamic adjustment of crustal materials in the middle-lower reaches of the Yangtze mainly occurred in the Mesozoic under the conditions of intense collision between the North China (Dabie) massif and the Yangtze massif. The structural adjustment refers to various types of deformation within the two massifs and the intensive shortening of the stratigraphic coyer of the Yangtze massif, whereas the compositional adjustment implies the structural remelting of the basement and the ore. and rock- forming processes in the two massifs.  相似文献   

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19.
Heavy metal contamination in the sediment of the Second Songhua River   总被引:1,自引:0,他引:1  
The Second Songhua River was subjected to a large amount of untreated effluent from petrochemical industries in Jilin City in the 1960s to the 1970s. The objectives of this study were to investigate the mercury and other heavy metal contamination in the sediment of the river. The river bottom sediment was sampled from the river segment between Jilin City to Haerbin City in 2005. Total concentrations of Hg, Cd, Cu, Cr, Pb, Zn, Ni, As, Sc, and major cations (A1, Fe, Mg, Ca, K, Na) in the sediment were measured by atomic fluorescence spectrometer, ICP-MS, and ICP-OES, respectively, following digestion with various acids. We found the concentrations of most elements in the uncontaminated sediment were significantly correlated to those of Sc.  相似文献   

20.
Water resource structure is one of the most important factors that constrain the economic development in arid–semiarid areas. Sustainable use of water requires a thorough understanding of the local geology and hydrology and developing of effective protection strategies. Discussed in this paper is a study on the phreatic water quality of the Yuxi River Valley of Shaanxi Province, China. The Yuxi River Valley passes through the Shaanbei energy base, which demands large quantities of high-quality water. A total of 129 water samples were collected in 4,938 km2 in a recent study to delineate the areas with water suitable for drinking, industrial, and agricultural usage and areas with poor quality. The study indicates that the poor quality of water contains high concentrations of NH4+ and NO2−1, indicating possible contamination by waste disposal in the nearby cities and towns. A series of strategies are proposed to protect the water in the Yuxi River Valley, including proper treatment and recycling of the waste water in the cities and towns, strict control of the waste-water discharge from any new factories and mines, and prevention of groundwater contamination by wastes containing heavy metals.  相似文献   

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