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1.
鞍本抚顺地区科马提岩的初步研究   总被引:1,自引:0,他引:1  
Komatiites have been discovered for the first time in the Lower Anshan Group with a metamorphic grade from amphibolite to granulite facies. Komatiites occur as bedded ultramafic volcanic rocks on the ocean-floor. The kematiites in the Region occurring in the metamorphic rocks are some monomineralic rocks such as hornblendite, monoclinie augitite and hypersthenite. Local komatiites are found retaining some typical pre-existing structures and textures of volcanic rocks, such as blastophitie texture and blastospinifex. The chemical composition of komatiites in this region is much similar to that of other well-known model komatiites in the world, and so are their geochemical charaeteristies. The occurrence of komatiites in the Anshan-Benxi-Fusun Region provide strong evidence to show that this region is an Archean greenstonc belt. Studies on komatiites in this region will shed much light on the stratigraphic division of the Anshan Groupand the paleostructure of the greenstone belt as well as on the rules governing metallogenesis in the Anshan-Benxi-Fusun Region.  相似文献   

2.
In the Triassic marine sediments, an obvious enrichment of lithium has been found. The source and enrichment mechanism of lithium is unknown. Here, we report trace and rare earth element and isotope analyses for Triassic sedimentary samples from core ZK601, recovered from the Huangjinkou anticline in the Xuanhan basin. Lithium concentrations from the Leikoupo and Jialingjiang formations are much higher than the average concentrations in the crust of eastern China and in other marine sediments. Lithium concentrations are highest at depths of 3300–3360 m (in argillaceous marine sediments), and Li is positively correlated with Rb, Ga, Zr, Nb and other trace elements. The range of δ7Li values in our samples is consistent with that in other Triassic marine carbonate rocks. Lithium concentrations and isotope ratios are negatively correlated in the argillaceous dolomite samples at depths of 3300–3360 m. We compared the results in this study with trace and rare earth elements in the clay from Sichuan and Chongqing, and propose that the clay in the argillaceous marine evaporites from Huangjinkou formed via the hydrolysis of volcanic ash during Early–Middle Triassic volcanic eruptions into brine basins, during which clay adsorbed Li from the brine and formed Li-rich argillaceous dolomites. The addition and hydrolysis of volcanic ash in the evaporative brine is also related to the formation of a new type of polyhalite.  相似文献   

3.
A New Ornithocheirid from the Early Cretaceous of Liaoning Province, China   总被引:5,自引:0,他引:5  
Based on a nearly complete skeleton with skull from the Early Cretaceous of Liaoning Province, a new ornithocheirid pterosaur: Boreopterus cuiae gen. et sp. nov. is erected. Boreopterus cuiae is different from other pterosaurs preserved with skulls known from the western Liaoning Province and its neighboring areas. Tiffs new oterosaur has more and larger teeth than those in other ornithocheirids. Its anterior nine pairs of teeth are larger than other teeth. The fourth pair of upper and lower teeth are slightly larger than the third pair. Overall, Boreopterus cuiae shows much small range of tooth size variation than Anhanguerapiscator and Coloborhynchus robustus. The new taxon shares with other ornithocherids in having a relatively large size of the third and fourth pairs of teeth.  相似文献   

4.
The major element composition of sound-producing sand is reported together with rare-earth elements (REE) and other selected elements for the first time. Rare-earth element concentrations in beach sands from Miyagi and Tottori in Japan were determined by induction-coupled, argon-plasma spectrometry (ICP-MS) to characterize the REE of sound-producing and silent sands relative to the parental rocks. Sound-producing sand beaches are very common and all over in Japan: five beaches in Miyagi and 2 in Tottori are selected with other silent sand beaches in the areas. Both sound-producing sand and silent sand samples from Miyagi and Tottori contain more than 60wt% of SiO2 and are composed mainly of quartz and feldspar. Miyagi sand samples are characterized by light REE enrichment and flat chondrite-normalized patterns that are similar to those of local source sandstone. However, all sand samples from Miyatojima in Miyagi show positive Eu anomalies, a characteristic feature not shown in other sand samples from Miyagi. Tottori sand samples also are characterized by high REE contents and remarkable positive Eu anomalies. The sands containing lower REE contents are due to high quartz and feldspar contents. Miyatojima sand samples and Tottori sand samples have high REE contents and show remarkable positive Eu anomalies due to the presence of feldspar. The best results are obtained using all of the geological methods and the Principal Component Analysis (PCA) as a measure of the similarity between sound-producing sand and silent sand. The difference between sound-producing sand and silent sand is obtained from the PCA results.  相似文献   

5.
The sizes and morphologies of hexagonal phase ZnO crystals were successfully controlled by a hydrothermal process in the presence of poly (acrylic acid) (PAA). The dosage of NaOH in this reaction system proved to be crucial in the growth process. With the increase of dosage from 0.7 g to 3.0 g, the morphologies of the ZnO crystals changed from nanoplates to microrods. Their optical properties were also investigated.  相似文献   

6.
Ground water from Mt. Fuji, located on the border of Yamanashi and Shizuoka prefectures, has relatively high concentrations of trace element vanadium. The concentration is about 50 μg/L around the mountain, and about 1 μg/L in other areas. The vanadium comes from the lava of the mountain. The water is utilized as a source of tap water around the mountain, and habitants are drinking and using the water for cooking. Recent reports by some researchers suggest health beneficial effects of drinking the water; drinking such water can lower blood glucose level in diabetic patients, and improve insulin-resistant status in healthy women. However, the concentration of vanadium in the ground water is too low as compared with the apparently effective concentration (100000 μg/L) in preceding reports. Furthermore, the effects of vanadium in the water on public health are not elucidated. In the present study the regional concentrations of vanadium in ground waters were investigated in Yamanashi prefecture, and standardized mortality rates (SMR) are compared preliminary with vanadium data in order to investigate the effect epidemiologically. SMR data were provided by Health, Labor and Welfare Ministry. We used the summarized SMR from 1998 to 2002. The data contain SMRs from total causes; total malignant neoplasm; stomach cancer; colorectal cancer; liver and intrahepatic bile duct cancer; trachea bronchus and lung cancer; all heart diseases; acute myocardial infarction; and cerebrovascular disease. There are eight secondary medical districts in Yamanashi prefecture, and one of them, Fuji-hokuroku (No.7), corresponds to high-vanadium area. No SMIL except SMR from cerebrovascular disease in female, was lower in the district No.7 than other eight districts. On the other hand, SMRs from all heart diseases and from acute myocardial infarction of both male and female in the district No.7 were highest among the districts. SMR from all causes in male of No.7 was also highest among the districts.  相似文献   

7.
<正>Through the statistical analysis of reservoir physical property,thin slice,scanning electron microscopy and mercury injection experiment data of Shahezi formation in Zhaozhou area,there are two main directions of provenance systems.One from central uplift belt in western,and other from slope zone in eastern.Reservoirs roughly grow in sandstone which in fan-delta in western  相似文献   

8.
The water, pore water, sediment, and fish samples were collected from the Hongfeng Reservoir in November 2003 and February 2004 in accordance with trace metal protocols. The average concentrations of total mercury (THg), dissolved mercury (DHg), reactive mercury, dissolved gaseous mercury, total methylmercury, and dissolved methylmercury in the water columns were 8.00, 5.70, 0.63, 0.05, 0.16, and 0.07 ng/L, respectively. THg and DHg in the water columns, THg in pore water and THg in lake sediments of the Hongfeng Reservoir showed the level of mercury in the Hongfeng Reservoir was higher than in other natural waters in the world due to the loading of a lot of waste water with relatively high concentrations of mercury, whereas methylmercury concentrations in fish (wet weight) varied from 1.73-51.00 ng/g, much lower than in most remote lakes and reservoirs reported in northern Europe and North America. Methylmercury distributions in pore water and sediments showed methylation occurred mainly in the upper several centimeters of sediment cores in the Hongfeng Reservoir. The concentrations of dissolved organic carbon, total suspended particles, total Hg, and methylmercury were higher at Houwu than those at Daba in November 2003. It is suggested that other pollutants such as N and P from fishing farm and other waste water at Houwu, which resulted in deterioration of water quality, affected the concentrations and distributions of mercury species in the reservoir.  相似文献   

9.
In the classic theory of plate tectonics, ophiolitic mantle peridotites (i.e., abyssal peridotite) are thought to originate in the shallow mantle beneath ocean spreading centers.Diamonds and other UHP minerals have been found in opholitic mantle peridotites and chromitites along the Neo-Tethyan Yarlung Zangbo suture of southern Tibet, and in a Paleozoic ophiolite in the Polar Urals of Russia,suggesting that UHP minerals may be widespread in ophiolitic peridotites.Diamonds from these different localities all have very similar features in C isotope and mineral inclusions,and are distinct from the other two well known types, i.e. kimberlitic diamonds and UHP metamorphicdiamonds. The occurrence of diamond in ophiolite indicate a completely new environment for diamond formation, which can be regarded as ophiolite-type diamond. These new findings indicate a need to reconsider the nature of the upper mantle and the conditions under which ophiolites form.  相似文献   

10.
Based on the meteorological and hydrologic data in the Lijang(丽江) basin from 1979 to 2006,variational trend and characteristics of climate change and its effect on runoff in Yanggong(漾弓) River were examined in the study.The results show that the temperature have significantly increased in the drainage basin during the past 28 years.The average temperature increased markedly from 1979 to 2006,and the increase of temperature in winter was higher than those in other seasons.The annual precipitation varied with...  相似文献   

11.
High-concentrated sulfur wastewater with sodium and COD (chemical oxygen demand) up to 26000 mg/L from a chemical plant, Jiangsu Province of China has been treated by deposition of natrojarosite in lab. The results indicated that the COD of the wastewater was decreased sharply from 26000 mg/L to 1001 mg/L, with removal rate of COD up to 96% by twice precipitations of natrojarosite and twice oxidation of H202. The treated sulfur wastewater reached the requirement of subsequent biochemical treatment to water quality. The optimal operational parameters should be controlled on pH value between 2.50 and 3.20 and 50 g FeCly6H2O solid added in per liter wastewater. The study provided an experimental basis for pretreatment of high-concentrated sulfur wastewater and proposed a new mineralogical method on treatment of other wastewaters. Depositing process of jarosite and its analogs should be able to be used to treat wastewater from mine and other industries to remove S, Fe and other toxic and harmful elements, such as As, Cr, Hg, Pb, etc. in the water.  相似文献   

12.
The Permian planktonic distribution is not well known, in contrast to other fossil distributions of nekton and benthos. Radiolaria are representative microfossils of plankton in the Permian palaeocean. This study compares both correlated radiolarian occurrences (Pseudotormentus De Wever et Caridroit and Quadriremis Nazarov et Ormiston) in literature data from the Pacific Rim and quantitative data from the Liuhuang and Gujingling sections in South China. Pseudotormentus distributions are concentrated in the Panthalassa, whereas Quadriremis occurrences are distributed over both the Panthalassa and the Palaeotethys. The uneven distribution of Pseudotormentus seems to have been controlled by a difference in the oceanic basins, indicating the presence of faunal differences in Permian planktonic microorganisms between the Panthalassa and the Palaeotethys. In other words, this study infers the provincialism of Permian planktonic microorganisms. The uneven distribution is explainable by a hypothesis that Pseudotormentus was strongly affected by a Panthalassan equatorial current.  相似文献   

13.
正1 Introduction Lithium was used widely in batteries,lubricants,aluminium smelting,ceramics,glass,polymers and other areas due to its unique electrochemical reactivity as well as other properties(Hykawy,2010).Production of lithium comes from both brine and mineral sources.The total resources of lithium estimated by the USGS in 2014 are to  相似文献   

14.
General charaeteristics of bird‘seye structure are discussed and distinctions are proposed between bird‘seye structure and a number of other features such as reerystallization, tiny holes resulted from dissolution and suncrack shrinkage. “Bird‘seye”commonly found in Southwest China owes their origin to gas bubble, shrinkage and other mechanisms,  相似文献   

15.
Previous studies have shown that the ascending, oxidizing brines play a very important role in Kupferschiefer mineralization. Fractures could be the pathway of the brines. In order to clarify the influences of the brines on bulk organic matter, aromatic hydrocarbons and Kupferschiefer mineralization, one veinlet Kupferschiefer profile from the Lubin mine, southwestern Poland was studied with the microscopic, geochemical and Rock-Eval methods. The microscopic results indicate that organic matter of the veinlet sample consists dominantly of bitumen. Its extract content is higher than in other samples. The dominant aromatic compounds are naphthalene and alkylated naphthalenes (Na-PAH), which have migrated into the veinlet sample from other sediments. The content of phenanthrene and its methylated derivatives (Ph-PAH) is much lower than in other samples. The reason may be due to their heavier mass than Na-PAH. It is more difficult for Ph-PAH to migrate. The Na-PAH was probably removed from the shale by dist  相似文献   

16.
The remarkable transition of early angiosperms from a small to a dominant group characterized the terrestrial ecosystem of the Cretaceous. This transition was instigated and promoted by environmental changes. Mid-Cretaceous is characterized by major geological events that affected the global environment. δ18O, palaeothermometer TEX86, and other climatic indices from marine sediments suggest rapid temperature increase during mid-Cretaceous despite occasional short cooling events. Simultaneously, terrestrial deposits in East Asia changed from coal-bearing to shale, then to red beds and evaporites. Plant assemblages and other paleoclimate indicators point to rapid aridification for mid-Cretaceous terrestrial environments. In addition, the wildfires were frequently spread all over the earth by the numerous charcoal evidence during the Mid-Cretaceous. Thus, we speculate that the seasonally dry and hot conditions of mid-Cretaceous created a fiery hothouse world. Early angiosperms increased in abundance and diversity and evolved from a few aquatic species to terrestrial herbaceous and then to the diversified flora of today. Angiosperms showed rapid physiological evolution in vein density and leaf area that improved photosynthesis and water absorption. These ecophysiological changes made early angiosperms well adapted to the hot and dry environment in mid-Cretaceous. Moreover, these physiological changes facilitated the fire–angiosperm cycles in mid-Cretaceous that likely further stimulated the early angiosperm evolution.  相似文献   

17.
正Production of lithium carbonate from brines has become the dominate trend in the world from the beginning of this century.Dangxiongcuo,a carbonate-type salt lake,is located in the interior of the Tibetan Plateau,China.As a salt lake deposit,rich in Li,B,K and other useful trace  相似文献   

18.
Colloform pyrite (CPy) is widely distributed in the Tongling mineralization cluster of the Middle–Lower Yangtze River Mineralization Belt (MLYRMB), China. There have many debates as to whether such CPy is associated with Late Mesozoic igneous or Carboniferous sedimentation. CPy from the Xinqiao deposit, a representative of the stratabound sulfide deposits in the MLYRMB, was studied by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (TEM). The results show that CPy mainly comprises pyrite, pyrrhotite, quartz, and illite. Pyrite in CPy shows cubic, globule, and xenomorphic morphologies. No octahedral or pyritohedron was observed. Most of the quartz crystals display xenomorphic morphology, where pyrite mold are popular on the surface. Organic matter (OM), which is usually bound to illite, is an important component in CPy. Morphological investigations which exhibit detrital features of quartz and clay minerals indicate that they were derived from continental weathering. Specially, some hexagonal pyrrhotite nanoparticles which show mackinawite morphology are coexisted with OM. The results indicate that the transformation process of sulfides possibly is mackinawite (the precursor)—hexagonal pyrrhotite—pyrite. Thus, compositional and micro-textural characteristics of CPy in Xinqiao deposit suggest it to be a sedimentary origin rather than a hydrothermal origin which is associated with Yanshanian magmatism. Moreover, the coexistence of CPy and stratabound sulfide orebodies in the MLYRMB suggests a causal link between the two. It is considered that CPy might have served as a Cu mineralization geochemical barrier for the Cu-bearing ore-forming fluids, which originated from the Mesozoic magma in the MLYRMB.  相似文献   

19.
<正>So far there has been no common opinion on oil source of the Chepaizi swell in the Junggar Basin.Therefore,it is difficult to determine the pathway system and trend of hydrocarbon migration, and this resulted in difficulties in study of oil-gas accumulation patterns.In this paper,study of nitrogen compounds distribution in oils from Chepaizi was carried out in order to classify source rocks of oils stored in different reservoirs in the study area.Then,migration characteristics of oils from the same source were investigated by using nitrogen compounds parameters.The results of nitrogen compounds in a group of oil/oil sand samples from the same source indicate that the oils trapped in the Chepaizi swell experienced an obvious vertical migration.With increasing migration distance,amounts and indices of carbazoles have a regular changing pattern(in a fine linear relationship).By using nitrogen compounds techniques,the analyzed oil/oil sand samples of Chepaizi can be classified into two groups.One is the samples stored in reservoir beds of the Cretaceous and Tertiary,and these oils came from mainly Jurassic source rock with a small amount of Cretaceous rock;the other is those stored in the Jurassic,Permian and Carboniferous beds,and they originated from the Permian source.In addition,a sample of oil from an upper Jurassic reservoir(Well Ka 6), which was generated from Jurassic coal source rock,has a totally different nitrogen compound distribution from those of the above-mentioned two groups of samples,which were generated from mudstone sources.Because of influence from fractionation of oil migration,amounts and ratios of nitrogen compounds with different structures and polarities change regularly with increasing migrating distance,and as a result the samples with the same source follow a good linear relationship in content and ratio,while the oil samples of different sources have obviously different nitrogen compound distribution owing to different organic matter types of their source rocks.These conclusions of oil source study are identical with those obtained by other geochemical bio-markers. Therefore,nitrogen compounds are of great significance in oil type classification and oil/source correlation.  相似文献   

20.
Well-preserved specimens of Kepingophyllum aksuence Wu et Chow were collected from Early Permian strata in western Tarim Basin, Xinjiang. More than 100 serial thin sections were made for this study. Kepingophyllum aksuence displays a unique increase pattern. The bud appears in lonsdaleoid dissepiments between the corallites where the wall of parent corallite disappears and the area becomes aphroid. This increase pattern is different from other lateral increases of most colonial rugose corals, and therefore has taxonomic significance to differentiate Kepingophyllidae from other compound rugose corals. It is also discussed that Kepingophyllum aksuence has a high “reproductive integration”, which means a rapid growth of buds during the offsetting process. Kepingophyllum was possibly originated from Ivanovia and was also a probable ancestor of Wentzellophyllum, which is supported here by more or less the similarity of the blastogeny in different stages of three taxa.  相似文献   

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