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1.
VitalyA.Stepanov 《东北亚地学研究》2004,7(2):173-180
The Bamsk gold-ore deposit is located in the Amur region, the Far East of Russia. It is confined to the Early Cretaceous volcanicoplutonic uplift of central type, located in the Stanov folded-clumpy Pre-Cambrian system. The deposit is presented by a series of gold-bearing quartz and carbonate-quartz vein-stringer zones. They are confined to the super-intrusive zone of the Nevachansk subvolcanic intrusion of sienite-porphyric composition. The mineralization is being controlled by zone of fractures developed in the autochthone of the Bamsk fault. Quartz, carbonates and sericite prevail in the composition of ores. The quantity of ore minerals doesn‘t exceed 1% ～ 5%. Pyrite, chalcopyrite, galena and native gold are widely spread, Sheelite, gold and silver tellurides, sulphobismuthites, acanthite, sphalerite and cinnabar are less developed. Four stages of mineralization have been distinguished. Gold-sulphide-sulphosalt ore with tellurides of gold and silver is productive for gold. The following set of elements is typomorphic for the ores of the deposit: Au, Ag, Cu, Bi, Mo, Pb and Sb (W1, Pb1, Mo) -Cu- (Ag, Bi, Sb, Mn, W2,, Pb2) form the vertical series of zoning. Rocks, enclosing the mineralization are exposed to the processes of listvenitization-beresitization. The processes of gumbeization and argillization are less manifested. The age of the gold mineralization, determined by Rb-Sr method on ore-accompanying minerals, is 130.6 Ma. 相似文献
2.
The changes of taxonomical composition of the Late Jurassic-Early Cretaceous palynofloras are revealed,in the upper stream of Bureya River in Bureya Basin.The palynofloras are dominated as follows:the Berriasian one by ferns(Cyatheaceae,Dicksoniaceae,Osmundaceae),Classopollis and bisaccate pollen;the Valanginian-Hauterivian one by ferns(Cyatheaceae,Dicksoniaceae),Ginkgocycadophytus and bisaccate pollen;the Barremian one by ferns(Cyatheaceae,Dicksoniaceae);the Aptian one by ferns(Cyatheaceae,Dicksoniaceae,Gleicheniaceae) and Ginkgocycadophytus;and the Albian one by ferns(Schizaeaceae) and bisaccate pollen.In the Albian the floral diversity raises with the angiosperms appearing. 相似文献
3.
Surface waves comprise an important aspect of the interaction between the atmosphere and the ocean, so a dynamically consistent framework for modelling atmosphere-ocean interaction must take account of surface waves, either implicitly or explicitly. In order to calculate the effect of wind forcing on waves and currents, and vice versa, it is necessary to employ a consistent formula- tion of the energy and momentum balance within the airflow, wave field, and water column. It is very advantageous to apply sur- face-following coordinate systems, whereby the steep gradients in mean flow properties near the air-water interface in the cross-interface direction may be resolved over distances which are much smaller than the height of the waves themselves. We may account for the waves explicitly by employing a numerical spectral wave model, and applying a suitable theory of wave–mean flow interaction. If the mean flow is small compared with the wave phase speed, perturbation expansions of the hydrodynamic equations in a Lagrangian or generalized Lagrangian mean framework are useful: for stronger flows, such as for wind blowing over waves, the presence of critical levels where the mean flow velocity is equal to the wave phase speed necessitates the application of more general types of surface-following coordinate system. The interaction of the flow of air and water and associated differences in temperature and the concentration of various substances (such as gas species) gives rise to a complex boundary-layer structure at a wide range of vertical scales, from the sub-millimetre scales of gaseous diffusion, to several tens of metres for the turbulent Ekman layer. The bal- ance of momentum, heat, and mass is also affected significantly by breaking waves, which act to increase the effective area of the surface for mass transfer, and increase turbulent diffusive fluxes via the conversion of wave energy to turbulent kinetic energy. 相似文献
4.
LIUYun JIANGGuoliang ZHANGShicui 《中国海洋大学学报(英文版)》2004,3(2):161-165
Histological study on the ontogeny of the lymphoid organs, kidney, thymus and spleen of Japanese flounder, Paralichthys olivaceus, from hatching to 40d was carried out. The pronephric kidney duct appeared early in hatching although the primordial haemopoietic stem cells wereobserved within a week after hatching. The spleen was first seen after 8d of hatching. The thymus appeared after 15d, situated near the pronephric kidney. Small lymphoid cells appeared during the later phase of the post-larval stage in the sequence of thymus, kidney and spleen. During the 40d of observations, there were no distinct inner or outer zones in thymus and no red or white pulp in spleen. These results suggest that the nonspecific defense immune system plays a very important role in the early larval stage of Japanese flounder. 相似文献
5.
《中国地理科学(英文版)》2007,17(2):192-192
Director: Zhang Bai Address: 3195 Weishan Road Changchun 130012 China Phone: 86-431-85542266 Fax: 86-431-85542298 E-mail: neigae@neigae.ac.cn Website: http://www.neigae.ac.cnNortheast Institute of Geography and Agroecology (NEIGAE), a component of Knowled… 相似文献
6.
ＩＮＴＲＯＤＵＣＴＩＯＮＮａｎｄＰｉｎｐｕｔｔｅｄｉｎｔｏＪｉａｏｚｈｏｕＢａｙｂｙｒｉｖｅｒｓａｎｄｂｙｓｅｗａｇｅｅｆｆｌｕｅｎｔｓｏｆｃｉｔｉｅｓ ,ｈａｖｅｍａｄｅｔｈｅＢａｙｂｅｃｏｍｅｍｏｒｅａｎｄｍｏｒｅｅｕｔｒｏｐｈｉｃｄａｙｂｙｄａｙ .Ｓｈｅｎ ( 1994)ｔｈｏｕｇｈｔｔｈａｔｐｈｙｔｏｐｌａｎｋｔｏｎｇｒｏｗｔｈｗａｓｌｉｍｉｔｅｄｂｙｔｈｅｃｈａｎｇｅｆｒｏｍｎｉｔｒｏｇｅｎｔｏｐｈｏｓｐｈｏｒｏｕｓ ;ａｎｄｔｈａｔｔｈｅｓｉｌｉｃａｔｅｃｏｎｃｅｎｔｒａｔｉｏｎｉｎＪｉａｏｚｈ… 相似文献
7.
ZHENGBo SUNShichun MALin 《中国海洋大学学报(英文版)》2004,3(2):171-174
The alien halophilous Artemia species, Artemia franciscana, was found in Chengkou Saltern and Yangkou Saltern of Shandong Province, P.R. China. Although the indigenous parthenogenetic Artemia is detectable, the exotic species is dominant in both salterns. The cross-breeding tests between the exotic A. franciscana and 5 bisexual Artemia species were conducted. The results of hybridization and morphological observations on the exotic A. franciscana are briefly presented in this short communication. 相似文献
8.
The economic system of mining city is of typical vulnerability characteristics that can be manifested by its high economic
sensitivity and lack of response capacity to the gradual depletion of regional mineral resources. Taking Fuxin City of Liaoning
Province as a case, this paper established an economic vulnerability assessment method integrating BP neural network with
vulnerability index, then carried out an economic vulnerability assessment of Fuxin during 1989–2006. The results indicate
that: 1) Affected by the gradual depletion of regional mineral resources, the economic development of Fuxin had kept high
economic sensitivity from 1995 to 2001, and the response capacity to cope with and adapt to the impacts of the perturbation
of mineral resources was weak and relatively lag. The evolution of economic vulnerability can be divided into three stages:
in 1989–1994, the economic vulnerability of Fuxin City decreased slowly; in 1995–2001, the beginning stage of economic transformation,
the economic vulnerability of Fuxin City went up rapidly; in 2002–2006, the economic vulnerability of Fuxin City descended
and showed a trend to be stable. 2) The influence of economic sensitivity on Fuxin’s economic vulnerability is more evident
than that of response capacity. 3) The decreasing supply of mineral resources and the simple industrial structure are main
factors leading to the economic sensitivity of Fuxin. 4) The improvement of economic response capacity of Fuxin has typical
characteristics of input-driven growth, and external assistance is of great importance to the rapid improvement of economic
response capacity of Fuxin. And 5) the change from the simple industrial structure to diversified one of Fuxin is still unaccomplished,
and the contribution of non-coal-based industry to local economic development is relatively limited.
Foundation item: Under the auspices of Key Program of National Natural Science Foundation of China (No. 40635030), Knowledge
Innovation Programs of the Chinese Academy of Sciences (No. KZCX2-YW-342, No. KZCX2-YW-321) 相似文献
9.
Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994 (12 seasonal investigations) provided
by the Ecological Station of Jiaozhou Bay revealed the characteristic spatiotemporal variation of the ambient concentration
Si∶DIN and Si∶16P ratios and the seasonal variation of Jiaozhou Bay Si∶DIN and Si∶16P ratios showing that the Si∶DIN ratios
were <1 throughout the year in Jiaozhou Bay; and that the Si∶16P ratios were <1 throughout Jiaozhou Bay in spring, autumn
and winter. The results proved that silicate limited phytoplankton growth in spring, autumn and winter in Jiaozhou Bay. Analysis
of the Si∶DIN and Si∶P ratios showed that the nutrient Si has been limiting the growth of phytoplankton throughout the year
in some Jiaozhou Bay waters; and that the silicate deficiency changed the phytoplankton assemblage structure.
Analysis of discontinuous 1962 to 1998 nutrient data showed that there was no N or P limitation of phytoplankton growth in
that period. The authors consider that the annual cyclic change of silicate limits phytoplankton growth in spring, autumn
and winter every year in Jiaozhou Bay; and that in many Jiaozhou Bay waters where the phytoplankton as the predominant species
need a great amount of silicate, analysis of the nutrients N or P limitation of phytoplankton growth relying only on the N
and P nutrients and DIN∶P ratio could yield inaccurate conclusions. The results obtained by applying the rules of absolute
and relative limitation fully support this view.
The authors consider that the main function of nutrient silicon is to regulate and control the mechanism of the phytoplankton
growth process in the ecological system in estuaries, bays and the sea.
The authors consider that according to the evolution theory of Darwin, continuous environmental pressure gradually changes
the phytoplankton assemblage's structure and the physiology of diatoms. Diatoms requiring a great deal of silicon either constantly
decrease or reduce their requirement for silicon. This will cause a series of huge changes in the ecosystem so that the whole
ecosystem requires continuous renewal, change and balancing. Human beings have to reduce marine pollution and enhance the
capacity of continental sources to transport silicon to sustain the continuity and stability in the marine ecosystem.
This study was funded by the NSFC (No. 40036010) and subsidized by Special Funds from the National Key Basic Research Program
of P. R. China (G199990437), the Postdoctoral Foundation of Ocean University of Qingdao, the Director's Foundation of the
Beihai Monitoring Center of the State Oceanic Administration and the Foundation of Shanghai Fisheries University. 相似文献
10.
DENG Jiafang SUN Fengyue XIN Wei XU Zhihe PAN Zhongcui WU Dongqian TIAN Nan 《世界地质(英文版)》2020,(2):78-91
The Beiya porphyry-skarn gold-polymetallic deposit is one of the largest gold deposits in China and it also contains significant amounts of silver and base metals.The ore-bearing monzonitic granite porphyry occurs as a stock,of which the skarn type gold-copper-iron ore bodies are controlled by the contact zone between alkali-rich monzonitic granite porphyry and the limestone,and the gold-silver polymetallic mineralization is controlled by interlayer structure.Alteration and mineralization occur around the intrusion and exterior of monzonitic granite porphyry.Ore mineral formation sequence is as follows:skarn minerals→magnetite→pyrite→chalcopyrite/bornite+pyrite+gold→pyrite+galena+gold(silver).Petrographic studies of fluid inclusions indicate that the following types of inclusions exist in the pre-mineralization quartz-pyrite stage:gas-liquid two-phase inclusions(L-type),three-phase inclusions with daughter minerals(D-type)and gas-rich inclusions(V-type).The colorless transparent quartz in the main gold-chalcopyrite-pyrite stage mainly consists of L-type and V-type inclusions,whereas the inclusions in the late gold-silver-galena stage are mainly L-type.The evolution of ore-forming fluids shows a trend from high temperature,high salinity to medium-low temperature and low salinity.Medium-low density fluids play a dominant role in mineral component migration and transportation.Fluid cooling and boiling are the main mechanisms of gold-copper precipitation,while the involvement of atmospheric water and pH reduction are the main mechanisms of gold-silver polymetallic precipitation.The fluids in the quartz-pyrite stage before mineralization and the main gold-chalcopyrite-pyrite stage are dominated by magmatic water,while in the gold-silver-galena stage the fluids are dominated by atmospheric water.Isotope tracers show that S and Pb are mainly derived from monzonitic granite porphyry,not from limestone of the Beiya Formation. 相似文献
11.
At Admiralty Bay of central King George Island, Keller Peninsula, Ull-man Spur and Point Hennequin are main Tertiary volcanic terranes. Field investigation and isotopic datings indicate that, there occurred three periods of eruptions ( three volcanic cycles) and accompanying N-toward migration of the volcanic center on Keller Peninsula. After the second period of eruptions, the crater collapsed and a cal-dera was formed, then later eruptions were limited at the northern end of the peninsula and finally migrated to Ullman Spur. Thus Keller Peninsula is a revived caldera, and its volcanism migrated toward E with time. Point Hennequin volcanism happened more or less simultaneously with the above two areas, but has no clear relation in chemical evolution with them, frequently it belongs to another independent volcanic center. 相似文献
12.
References： 《东北亚地学研究》2007,10(1):6-10
The changes of taxonomical composition of the Late Jurassic- Early Cretaceous palynofloras are revealed, in the upper stream of Bureya River in Bureya Basin. The palynofloras are dominated as follows： the Berriasian one by ferns （Cyatheaceae, Dicksoniaceae, Osmundaceae）, Classopollis and bisaccate pollen; the Valanginiar-Hauterivian one by ferns （Cyatheaceae, Dicksoniaceae）, Ginkgocycadophytus and bisaccate pollen; the Barremian one by ferns （Cyatheaceae, Dicksoniaceae）; the Aptian one by ferns （Cyatheaceae, Dicksoniaceae, Gleicheniaceae） and Ginkgocycadophytus; and the Albian one by ferns （Schizaeaceae） and bisaccate pollen. In the Albian the floral diversity raises with the angiosperms appearing. 相似文献
13.
XIAO Li-mei SUN Feng-yue 《东北亚地学研究》2005,8(1):65-71
Gaotaigou borate deposit in Ji＇an area, southeastern Jilin, is located in the easten end of Liaoning-Jilin （Liaoji） Proterozoic paleo-rift, which is a medium-sized deposit and makes up 67% of the total borate reserves in Jilin Province. The original borate ore bodies were formed by sedimentary exhalative process in Paleoproterozoic, but were activated and enriched by later metamorphism. In late stage of metamorphism, hydrothermal fluid of metamorphic origin made wallrocks be altered and the borate ore bodies be reformed. Ore bodies are strictly controlled by strata and their lithologies. In addition, the shape and spatial distribution of ore bodies are also defined by the Gaotaigou syncline. Combined with the ore-controlling factors and mineralizing features, it has been proposed that Gaotaigou borate deposit is a metamorphosed and hydrothermally altered sedimentary exhalative deposit. 相似文献
14.
XIAO Li-mei SUN Feng-yue College of Earth Sciences Jilin University Changchun Jilin China 《东北亚地学研究》2005,(Z1)
Gaotaigou borate deposit in Ji'an area, southeastern Jilin, is located in the easten end of Liaoning-Jilin (Liaoji) Proterozoic paleo-rift, which is a medium-sized deposit and makes up 67% of the total borate reserves in Jilin Province. The original borate ore bodies were formed by sedimentary exhalative process in Paleoproterozoic, but were activated and enriched by later metamorphism. In late stage of metamorphistn, hydrothermal fluid of metamorphic origin made wallrocks be altered and the borate ore bodies be reformed. Ore bodies are strictly controlled by strata and their lithologies. In addition, the shape and spatial distribution of ore bodies are also defined by the Gaotaigou syncline. Combined with the ore-controlling factors and mineralizing features, it has been proposed that Gaotaigou borate deposit is a metamorphosed and hydrothermally altered sedimentary exhalative deposit. 相似文献
15.
《中国海洋湖沼学报》1996,(1)
To be placed on the lower part of the title page, or on a separate pageIt should be no longer than 5% of the article. 相似文献
16.
《中国海洋湖沼学报》1995,(2)
To be placed on the lower part of the title page, or on a separate page,It should be no longer than 5% of the article. 相似文献
17.
1 INTRODUCTIONThepenaeidshrimpcultureindustriesintheworlddevelopedfromtheirexperimentalbeginningslessthanthirtyyearsagointoamajoraquaculturein dustrytodaythatprovideshundredsofthousandsofjobs,billionsofU .S.dollarsinrevenue,andaug mentstheglobalfoodsupplywithahighvaluecrop(LighterandRedmam ,1 998) .Upto 1 995,farmedshrimpatvolumeof71 2 0 0 0MT ,almostallconsistingofPenaeidspecies,accountedfor 2 7%ofworldshrimpproduction.Inthatyear,asoneofthemostimportantculturedshrimp,theproductionofP… 相似文献
18.
Powerful alluvial rivers in the northern Alborz mountain ranges erode river banks due to having high slopes.Most of these rivers flow in forest areas.In this research,the rate of the river bank erosion was examined using the exposed roots of the trees.For this purpose,8 reaches of Lavij Stream were investigated.To determine the first year of root exposure,two sets of macroscopic and microscopic indicators were utilized.Accordingly,the rate of the stream bank erosion was estimated.The results were analyzed by using statistical test,which showed insignificant differences between the two groups of indicators.Due to its more abundance(frequency)on the margins and easy detection of its root through the exposure(macroscopic and microscopic)indicators,Alnus glutinosa(black alder)species could be more easily and accurately analyzed as compared with any other tree species in the region.The mean erosion rate of the riverbank using the extruded roots was estimated to be 0.08 m/yr.The hydrological analyses of flood flows showed that 95%of Lavij Stream bank erosion was caused by the river bank full discharges with a return period of 1-3 years. 相似文献
19.
《中国海洋湖沼学报》1996,(3)
To be placed on the lower part of the title page, or on a separate page,It should be no longer than 5% of the article. 相似文献
20.
Effects of temperature, pH and NaCl on protease activity in digestive tract of young turbot, Scophthalmus maximus 总被引：3，自引：0，他引：3
1 INTRODUCTION Digestive enzyme activity is one of important issues for learning digestive physiology of fish, and widely applied in commercial fish culture. So far, the data obtained in fish showed that the diges- tive enzymes were qualitatively similar … 相似文献