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1.
广西南丹铁陨石雨的发现 总被引:1,自引:0,他引:1
The distribution and exterior characters of each individual meteorite are presented for the iron meteorite shower in Nantan County, Kwangsi Chuang Autonomous Regiou,China. Nineteen iron meteorites have been found up to date, umounting approximately to 9,500 kg in total weight and spreading over an area of about 30 square kilometers. As compared with other iron meteorites known in China, they are much larger in size and contuin much more mineral species. It is also interesting to note that a complete sample of various parts of a primitive meteorite can be expected. The discovery of this meteorite shower is considered to be of significant value in science. 相似文献
2.
Based on structural observations and the concentrations of Cr, Co, Ni, Cu, Ga, Ge,As, Sb, Re, Ir and Au by neutron-activation analysis we have classified 14 Chinese iron meteorites. Thirteen are members of the large groups IAB, IIICD, IIICD,IIIAB and IVA.Leshan is an ungrouped iron meteorite that falls within the IIE field on some elementNi diagrams, but is distinctly outside this .fiel on plots of Cu, W, and Ir vs. Ni; it is very similar in Composition to Techado,another ungrouped iron. The high Cu content of Leshan is consistent with other evidence indicating that Cu is a valuable parameter for classifying, iron meteorites. IIICD Dongling appears not to be a new meteorite, but to be paired with Nantan; Dongling was recovered about 50 km from the location of the Nantan shower. Yungning is highly oxidized; we assign it to group LAB but cannot rule out IIICD. IVA-An Longchang has many characteristics of IVA irons, but has been remelted, prebably in a terrestrial setting, Five irons belong to group IVA, a remarkably large number. Three are identical in Composition, and we suspect that the two from Hubei, Guanghua and Huangling, are paired. Thus this set of 14 irons ineludes 12 independent fall. 相似文献
3.
The Ningbo iron meteorite fell near Ningbo, Chekiang province, on October 4,1975. 103 days later, γ-ray spectrum of the meteorite, was undestructively measured by a low-level γ-ray spectrometer. It is shown that the specific activity of Mn^34 present in the Ningbo iron meteorite is ap proximately close to that of Mn^34 in the Bogou and Aroos meteorites, while the specific activity of Co^37 seems to be higher in the Bogou and Aroos than in the Ningbo. 相似文献
4.
SONG Tianrui ZHENG Ning LIU Yongqing KUANG Hongwei PENG Nan LI Chao TANG Jigang YAN Qinggao GAO Linzhi ZHU Zhicai XIA Xiaoxu WANG Yuchong 《《地质学报》英文版》2020,94(1):38-56
This study covers cosmic spherules derived from the Mesoproterozoic Dahongyu Formation in the Ming Tombs area, Beijing. The cosmic spherules include iron oxide cosmic spherules, carbonaceous chondrites, and atomic iron “steely bead”-shaped cosmic spherules. The mineral assemblage of silicon carbide, forsterite, zircon, and glass spherules and fragments were picked from melt-silicified carbonate of the Mesoproterozoic Dahongyu Formation (ca. 1625 Ma). Cosmic spherule assemblages are solely discovered from sedimentary rocks in China. Platinum group elements (PGE) were determined for the first time in cosmic spherules and associated minerals. PGE comparative observation between meteorite and cosmic spherules is presented in this study. It is recognized that an extraterrestrial meteorite impact event might have occurred in the Dahongyu Stage. The main evidence is a large number of iron cosmic spherules in silicified oncolitic limestone, and associated cosmic silicon carbide, glass spherules, and fragments, as well as the presence of forsterite. The impact-volcanic crater is characteristic of a big black shale block dropped into the bended silicified limestone. 相似文献
5.
Using X-ray photoemission spectroscopy (XPS), the Preliminary results on the lunar basalt sample (70017-291)are shown in the paper. Major elements (O, Si,Al, Fe, Ca, Mg, Ti, etc.) of the lunar sample are similar to that of the Jilin meteorite and the Allende meteorite. The valence of iron in the sample has also been studied in detail. The authors suggest that Fe^ may be differentiated from Fe^ in the XPS spectra in terms of the satellite lines of Fe(2p3/2). 相似文献
6.
Iron meteorites from Nandan, Guangxi ; Wushike, Xinjiang; Shangdu, Hebei and Huangling, Hubei are investigated with a spark souree mass speetrometer for their Cr, Ni, Co, Cu, Zn, Ga, Ge, As, Mo, Ru, Rh, Pd, Os and Ir contents. The accuracy of the results and the factors affecting it are discussed. It is preliminarily concluded,while textural evidences of these meteorites are also taken into account, that the Nandan, Wushike and Shangdu meteorites belong to IA, Ⅲ .4 and ⅢE groups respectively. The Ni, Ga and Ge contents in the Huangling iron meteorite come close to that of mesosiderites. 相似文献
7.
Ramakant R. Mahajan 《地学前缘(英文版)》2017,8(1):205-210
The Sulagiri meteorite fell in India on 12 September 2008,LL6 chondrite class is the largest among all the Indian meteorites.Isotopic compositions of noble gases(He,Ne,Ar,Kr and Xe) and nitrogen in the Sulagiri meteorite and cosmic ray exposure history are discussed.Low cosmogenic(~(22)Ne/~(21)Ne)_c ratio is consistent with irradiation in a large body.Cosmogenic noble gases indicate that Sulagiri has a 4πcosmic-ray exposure(CRE) age of 27.9 ± 3.4 Ma and is a member of the peak of CRE age distribution of IX chondrites.Radiogenic ~4He and ~(40)Ar concentrations in Sulagiri yields the radiogenic ages as 2.29 and4.56 Ca,indicating the loss of He from the meteorite.Xenon and krypton are mixture of Q and spallogenic components. 相似文献
8.
《《地质学报》英文版》1986,(3)
The etouchang-typeiron deposit is a typical stratabound deposit in the northern part of central Yunnan. The discussion centres on the controlling effect of the generation and development of the structural system in the orefield on the formation of this type of deposit and establish a time-space ore-control model so as to get a better understanding of the mechanism for its formation.During the formation and enrichment of the Etouchang-type iron deposit, the structures performed a dual control function on the generation and distribution and also on the reformation and enrichment of the source bed. The Etouchang-type iron deposit is a typical example for the stratabound deposits of which the formation and distribution are controlled by the generation and development of structural systems.During the embryonic period of the longitudinal structural system shortly after the Dongchuan movement, a N-S rift valley-type trough appeared between the Lüzhijiang fault zone and the Luoci-Yimen fault zone. It was along the marginal areas of the trough that the iron-rich clay and sand of dominant terrigenous origin were accumulated, constituting the source bed of iron.During the Jinning movement, the basement had been finally formed and the longitudinal structural system took shape. During the Chengjiang movement, the longitudinal structural system was strengthened and the central Yunnan xi-type structure appeared, which controlled the activities of the Na-rich magma and thermal fluids, and the consequent reformation of the source bed, themigration and enrichment of iron substance and the formation of economic deposits. The LuociYimen fault zone controlled the distribution of the iron orefield while the lateral structures(e. g., the Etouchang compounding shear structure) controlled the occurrence of the deposit.The reformation and enricbment of the Etouchang-type iron deposits were concomitant with the formation of an ore-controlling structure. The scale and grade of the orebodies were strictly controlled by the structural pattern, and the orebodies occurred in the shear structures and were enriched in the tensional portion of a compressive structure. 相似文献
9.
A New Martian Meteorite from Antarctica:Grove Mountains (GRV) 020090 总被引:15,自引:0,他引:15
MIAOBingkui OUYANGZiyuan WANGDaode JUYitai WANGGuiqin LINYangting 《《地质学报》英文版》2004,78(5):1034-1041
Reported in this paper are the petrology and mineral chemistry of GRV 020090, the second Martian meteorite collected from the Grove Mountains, Antarctica. This meteorite, with a mass of 7.54 g, is completely covered by a black and glazy fusion crust. It has two distinct textural regions. The interstitial region is composed of euhedral grains of olivine, pigeonite, and anhedral interstitial maskelynite, with minor chromite, augite, phosphates and troilite. The poikilitic region consists of three clasts of pyroxenes, each of which has a pigeonite core and an augite rim. A few grains of subhedral to rounded olivine and euhedral chromite are enclosed in the pyroxene oikocrysts. GRV 020090 is classified as a new member of lherzolitic shergottites based on the modal composition and mineral chemistry. This work will shed light on the composition of Martian crust and magmatism on the Mars. 相似文献
10.
The Xi Ujumqin meteorite fell in Aug. 1980 at Xi Ujumqin County, Nei Monggol, China.This chondrite can be classified as L6 type based on the bulk chemical analysis (6wt% metal iron, 24% total iron, olivine Fa-26) and the textural feature of complete intergrowth of the chondrules with the matrix, The Mianchi meteorite is a type Hs chondrite that fell in Sep, 1980 at Mianchi County,Henan, China. Apart from porphyritic, barred, radial, cryptocrystanine chondrules, many intermediate-type or mixed-type chondrules are observed in the Mianchi meteorite under the microscope. It is suggested that the origin of chondrules showing different textures depend on the primeval compositions and cooling rates, 相似文献
11.
Production and storage-transportation of crude oil can not only give rise to soil pollution but also
destroy ecological environment.Degradation of microbes for oily soil was studied with the strument,Geofina Hydrocarbon Meter(GHM),by experimental analysis qualitatively and quantitatively in the paper.Analytical result showed that the crude oil could be considerably degraded by eating-oil microbes in oily soil and the number of eating-oil microbes increased while the working hours of oil-well rising.As a result,contaminated oil could be degraded more quickly by a lot of eating-oil microbes in the soil.At the same time,the degradation rate of contaminated oil increased gradually as the time went on.In addition,amount of gaseous component in the oily soil samples increased with degraded time and the microbes could selectively consume contaminated oil strongly,so biodegradation might alleviate the degree of contamination and destruction to the soil and environment in the process of oil production at oilfield.The law of oily soil degraded by microbes was investigated and some useful conclusions were drawn in the paper. 相似文献
12.
Precambrian Geochronology, Chronotectonic Framework and Model of Chronocrustal Structure of the Zhongtiao Mountains 总被引:8,自引:0,他引:8
The Zhongtiao Mountains, a typical exposure area of Precambrian rocks, are a concentration area of vari-ous types of copper deposit. The rocks were dated using several dating methods. Based on the age data ob-tained by means of three methods, several aspects are dealt with: (1) the dating results obtained by differentmethods and their geological implications have been compared; (2) a chronotectonic framework has been con-structed by means of these reliable ages, which indicates that the ages of the rocks of the Proterozoic mobilebelt fall in a time span of 2400 to 2000 Ma during which global magmatic records are lacking and reflects theages of important events in the mobile belt; (3) according to the ages of inherited zircons, neodymium modelage of the depleted mantle sources (T_(DM)) and geochemical and geological data, a model of Precambrianchronocrustal structure has been constructed, representing a typical for the North China craton. 相似文献
13.
Luong Van Viet 《地下水科学与工程》2021,9(1):20-36
The purpose of this paper was to assess the impact of urbanization on the groundwater level(GWL)in aquifers of Binh Duong(BD)Province.The research method is to analyze the trend of GWL,the recharge capacity of surface over time and the relationship between them.The data of the GWL used in the study are the average values in the dry and rainy seasons of 35 observation wells from 2011 to 2018,which are in Pleistocene and Pliocene aquifers.The ability to recharge groundwater from the surface in this study was represented by the curve number(CN),a parameter used in hydrology for calculating direct runoff or infiltration from rainfall.The land use data to identify the CN was analyzed from the Landsat images.The results show that besides over-exploitation,the change of surface characteristic due to the urbanization development process is also the cause of the GWL decline.The analysis of seasonal GWL data shows that the increase in impervious surface area is the cause of GWL decline in the Pleistocene aquifer,which is more evident in the rainy season than in the dry season.The statistical results also show that in the rainy season and in shallow aquifers,a higher CN change can be found with the wells that had a remarkable GWL decline compared to the remaining wells. 相似文献
14.
Cosmogenic radioactive nuclides, particularly K^40, Mn^54 and Co^57 are measured in meteorites Nos. Ⅰ,Ⅱ and Ⅴ from the Kirin meteorite shower which is very seldom to be met with in world history in the sense of its scale. Brief accounts are given of the distribution of cosmogenic nuclides with depth, the characteristics of cosmicray induced reactions and that of target nuclides, the energy region of bombarding particles, and the relative positions of meteorites Ⅰ,Ⅱ and Ⅴ with respect to the original meteoroid. The variations in Mn^54, Co^57 and K^40 with depth in No. I Kirin meteorite provides an excellent example for studies in this field. 相似文献
15.
Reorted in the present paper are some preliminary results of the studies on the petrochemistry and mineral compositions of various skarn zones in the Dapingdi iron deposit,the chemical compositions of iron ore and magnetite,and trace elements,sulfur isotopic compositions and F contents of skarns and iron ore.On the hasis of these data the authors have discussed the possibie relations between skarnization and the formation of iron ore.Moreover,the principal factors controlling skarnization and related mineralization are also discussed.It is suggested that skarnization and related mineralization are mainly controlled by the chemical composition,temperature,and pH and Eh of ore solutions.Pressure can only play a little role although it should be taken into consideration. 相似文献
16.
Presented in this paper are some results of simulating experiments on the geochemical behaviours of iron and aluminium during chilling of silicate meh and on the effect of iron on the behaviours of trace elements U, Mo, Zr, and Ba with a sealed arc apparatus. Experimental results indicate obvious fusing separation of iron and aluminium and their Partial concentration in the silicate melt when the contents of iron and aluminium in the samples are in excess of 4.35%. Furthermore, the effect of fusing separation of iron on the behaviours of trace elements U, Mo, Zr, and Ba is evident. Experimental study has shown that it is possible to avoid iron fusing separation by changing its atomic valence state with the oxidation method. 相似文献
17.
Based on the analysis of siderite distribution,occurrence,chemical compositionk,structureal characteristics,carbon-oxygen isotopic characteristics and relationship between siderite and hematite,this paper presents a systematic study of siderite in the region studied.suggesting that the siderite in the Xuanlong area genetically resulted from organically reduced primary hematite during the diagenesis.The ferric and ferrous relations directly depend on organic contents.In the presence of organic matter ferrous iron can be converted to ferric iron through or ganic reduction.The above conclusion has also been proved by organic geochemistry.data. 相似文献
18.
Based on the daily minimum temperature data in China from 1961 to 2018, using n-order polynomial fitting, sliding t-test, empirical Orthogonal Function analysis, Morlet wavelet transform and other methods, this paper reveals the temporal and spatial distribution characteristics of the number of cold surge (CS) day, CS frequency and CS intensity by time and region. The results are as follows. On a national level, the number of CS day, CS frequency, and CS intensity decreased from 1962 to 2000. Specifically, the trend of every element of CS has changed from a previous decrease trend to an increase trend, and the inflection point was around 2000. The CS activity occurred more frequently, became more strengthen, and last for longer time after 2000. There are obvious spatial differences in the number of CS days, CS frequency, CS intensity and their changing trends in China. The number of CS days and CS frequency reach the maximum value in northeast China and northern Inner Mongolia. Meanwhile, the CS intensity value is low in the southeast China and high in the northwest China, with the exception of southern Xinjiang. The changes in the number of CS day and the CS frequency are mainly manifested as the “Northeast, Southwest Reverse Pattern”, the CS intensity is mainly manifested as the “Uniform Change Pattern”. The number of CS day, CS frequency, and CS intensity did not change significantly after, but a significant transition point was detected in 1980. On a regional scale, from 1962 to 2018, the number of CS day, frequency and intensity of cold surge in all regions showed a decreasing trend, while they increased after 2000. In the northern and northeastern of China, mean of three elements of cold surge increased after 2000. The transition year was different in different regions. The transition year of three elements of cold surge in Northeast China were the earliest. Mean value of the number of CS day, CS frequency, and CS intensity have an oscillation period of 3~5 years in total China and all regions. In addition, the periodic oscillations of the number of CS day and CS frequency in all regions are basically the consistent. © 2022 Science Press (China). 相似文献
19.
LU Ren MIAO Bingkui WANG Guiqing DAI Deqiu LIN Yangting OUYANG Ziyuan LI Chunlai Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou Graduate School Chinese Academy of Sciences Beijing Institute of Geology Geophysics Chinese Academy of Sciences Beijing Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou Guangdong National Astronomical Observatories Chinese Academy of Sciences Beijing 《《地质学报》英文版》2004,78(5):1052-1059
Petrography and mineral chemistry of 24 ordinary chondrites from the Grove Mountains, Antarctica, have been studied in order to identify their chemical-petrographic types. These samples were selected from a total of 4448 Grove Mountains (GRV) meteorites collected during the 19th Chinese Antarctic Research Expedition so as to make an estimation of the large GRV meteorite collection. The chemical-petrographic types of these meteorites are presented below: 1 H3,2 H4, 4 H5, 2 H6, 1 L4, 7 L5, 5 L6, 1 LL4 and 1 LL6. The new data weaken the previous report that unequilibrated ordinary chondrites are unusually abundant in the Grove Mountains region. However, this work confirms significant differences in distribution patterns of chemical-petrographic types between the Grove Mountains and other 相似文献
20.
Presented in this paper are the rypes,salinities,homogenization temperatures and organic components of fluid inclusions formed at the four stages of diagenetic authigenesis in the Eogene of the Biyang Depression.The results of cooling experiments on fluid inclusions were used to determine the fluid system and composition of saline aqueous solution in each of the stages .The homogenization temperatures of saline aqueous solution inclusions and hydrocarbon organic inclu-sions have been corrected by two approaches ,and the trapping temperatures and pressures of fluid inclusions at each of the stages have been obtained.This strdy has shed light on the physicochemistry and evolution of diagenetic fluids.The diagentic fluid system is a system which was transformed from a chloride-bearing to a carbonate-bearing system along with the diagenic evolu-tion.The decrease of diagenetic temperature at Stage III of diagenetic authigenesis suggests that the depression would have experiences uplifting at that time.The fluorescent characteristics of fluid inclusions indicate the varieties of organic components in fluid inclusions both in time and in space. 相似文献