首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
Quantitative analysis of Apollo-17 mare basalt (70017-291) was carried out for its containing 26 elements by instrumental neutron activation technique with the rock standard BCR-1 prepared by the U.S. Geological Survey as the multielement irradiation standard. For most of the elements, the analytical error is confined to 10%. A comparison was made of the analytical results with those obtained from Apollo-11 and Apollo-12 mare basalt samples.  相似文献   

2.
The results of Moessbauer study of Apollo-17 Mare basalt are reported in this paper.It has been revealed that Fe in iron.bearing minerals in the basalt is almost present in the form of Fe^3 , with Fe^3 less than 3% of total iron. The site occupancy of Fe^3 ions at M1 and M2 is approximately 0.3 and the corresponding equilibrium constant K (T) is about 0.06, thus indicating that the mare basalt is formed through crystallization under high-temperature reducing and rather slow cooling conditions.  相似文献   

3.
Chemical, petrological and mineralogical studies on 70017-291 Mare basalt indicate that the mare basalt belongs to Type B of A-17 basalts with a texture of plagioclasepoikilitic ilmenite basalt. The mean chemical composition of this basalt is as follows:SiO2 39.01, TiO2 11.32, Al2O3 9.24, FeO 18.52, MgO 8.61, CaO 10.86 (%). INAA measurements were made on the basalt for major, minor and trace elements. Seven pyroxene grains in the Apollo 17 were also analyzed by microprobe. They show two compositions, one for pigeonite, and the other for augite-subcalicaugite. The mean composition of pigeonite is Wo10.85, En59.33 Fs30, and that of augite-subcalic augite Wo25 En41.5Fs38.3. Plagioclase grains have a composition ranging from An30 to An96. The plagioclase contains detectable iron (averaging 0.74%), potassium (0.089% in average) and titanium(averaging 0.16%). The mean composition of ihnenite is TiO2 53.98%, FeO 41.02%,Al2O3 0.21%, MgO 2.41%, Cr2O3 0.74%. The Ti-high mare basalt (70017-291) was formed by partial melting of the early cumulates through assimilation and migmatization. On the whole, mare basalts seem to be of multigenesis.  相似文献   

4.
<正>1 Introduction Lunar mare basalts represent the products of partial remelting of deep mantle sources and provide windows into the compositions of lunar interior.Nine Apollo andLuna missions returned large amounts of mare basaltic samples,while remote sensing suggests that sampled basalts may cover only a small number of the lunar basalt  相似文献   

5.
Two new lunar mare soil simulants, NAO-2 and NAO-3, have been created in National Astronomical Observatories (NAO), Chinese Academy of Sciences. These two simulants were produced from low-titanium basalt and high-titanium basalt respectively. The chemical composition, mineralogy, particle size distribution, density, angle of internal friction, and cohesion of both simulants have been analyzed, indicating that some characteristics of NAO-2 and NAO-3 are similar to those of Apollo 14 and Apollo 11 landing site soils. NAO-2 and NAO-3 will be of great benefit to the scientific and engineering research on lunar soil.  相似文献   

6.
The Sinus Iridum region, the first choice for China's"Lunar Exploration Project"is located at the center of the lunar LQ-4 area and is the site of Chang'e-3 (CE-3)'s soft landing. To make the scientific exploration of Chang'e-3 more targeted and scientific, and to obtain a better macro-level understanding of the geotectonic environment of the Sinus Iridum region, the tectonic elements in LQ-4 region have been studied and the typical structures were analyzed statistically using data from CE-1, Clementine, LRO and Lunar Prospector missions. Also, the mineral components and periods of mare basalt activities in the study area have been ascertained. The present study divides the tectonic units and establishes the major tectonic events and sequence of evolution in the study area based on morphology, mineral constituents, and tectonic element distribution.  相似文献   

7.
The basalt terrain of the Neogene Huangguoshan and. Guiwu Formations of eastern Anhui on the east side of the Tancheng-Lujiang fault belt is one of a few Cenozoic basalt terrains in eastern China for which detailed geochemical study has not been conducted. This paper reports the abundances of major elements and more than 20 trace elements (including REE) of 22 samples and the Nd, Sr and Pb isotopic compositions of 11 samples from the eastern Anhui basalt terrain, thus more or less systematically revealing the geochemical characteristics of this continental basalt suite. The paper discusses the origin of the basalt suite and the character and process of its mantle source. The basalt suite was derived from a heterogeneous continental lithospheric mantle with end members characteristic of the EMI-type oceanic basalt mantle, which was affected by mantle metasomatism (or enrichment of trace elements) and was characterized by a multi-stage evolution under open conditions.  相似文献   

8.
Experimental research on the chemical weathering of alkaline-olivine basalt from Huangyi Mountain,Kuandain County,Liaoning.Province and olivine basalt from Dayangke,Mingxi County,Fujian Province has shown that the acidity of the solution tends to become neutral regardless of what the acidity of the starting solution would be during basalt0-water interaction.We call this phenome-non“pH neutralized Effect”.The dissolved species in the solution were determined and unreacted and reacted sample-surface chemical components involved or uninvolved in reaction were analyzed using X-ray photoelectron spectroscopy(XPS).The results revealed two different mechanisms of dissolution of basalt in acidic and basic solutions.  相似文献   

9.
KREEP Rocks   总被引:2,自引:1,他引:2  
KREEP rocks with high contents of K, REE and P were first recognized in Apollo-12 samples, and it was confirmed later that there were KREEP rock fragments in all of the Apollo samples, particularly in Apollo-12 and -14 samples. The KREEP rocks distributed on the lunar surface are the very important objects of study on the evolution of the moon, as well as to evaluate the utilization prospect of REE in KREEP rocks. Based on previous studies and lunar exploration data, the authors analyzed the chemical and mineral characteristics of KREEP rocks, the abundance of Th on the lunar surface materials, the correlation between Th and REE of KREEP rocks in abundance, studied the distribution regions of KREEP rocks on the lunar surface, and further evaluated the utilization prospect of REE in KREEP rocks.  相似文献   

10.
正The detailed structures of the plumbing system of the early Permian Tarim flood basalt were investigated by 3-D seismic imaging.The images show that the Tarim flood basalt mainly erupted from central volcanoes distributed  相似文献   

11.
To illuminate the migration and transformation of selenium(Se)in the igneous rock-soil-rice system,285 pairs of rhizosphere soil and rice samples were collected from the granitoid and basalt areas in Hainan Province,South China.The contents of Se in soils derived from granitoid and basalt are,respectively,0.19±0.12 mg/kg and 0.34±0.39 mg/kg,which are much higher than Se contents in granitoid and basalt.Selenium shows remarkable enrichment from granitoid and basalt to soils.The mobile fraction of Se in soils derived from granitoid is 0.0100±0.0034 mg/kg,which is significantly higher than that of basalt(0.0058±0.0039 mg/kg).Although soil derived from basalt shows higher Se contents,Se contents in rice samples,mobile fractions of Se in soils,and biological concentration factor(BCF)is similar or even lower than that from granitoid.Basalt consist of calcic plagioclase and pyroxene,and are much richer in Fe,Al,and Ca than granitoid.Correspondingly,the basalt-derived soils have higher goethite,hematite,kaolinite,cation exchange capacity(CEC)content,and higher p H than the granitoid-derived soils,which result in higher adsorption capacity for Se and relatively lower Se bioavailability.Soils derived from granitoid and basalt in tropical regions are beneficial to produce Se-rich rice.  相似文献   

12.
The Dachang antimony deposit in Qinglong,Guizhou Province,is strictly controlled by the “Dachang Layer” which is a complex altered rock occurring at unconformity between the Permian Emeishan basalt and the Maokou limestone.Based on the studies of the hanging-and foot-wall rocks,the trace elements and REE contents of the rocks and ores and heavy placer minerals in the basalt,this paper is focused on the relations between these data and the “Dachang Layer”and its hanging- and oot-wall rocks.The author pointed out that the “Dachang Layer” and basalt are the source-beds of antimony;ilmenite and magnetite are the major mineral carriers of antimony.In the processes of halmyrosis and burial metamorphism of the “Dachang Layer” an basalt,antimony was mobilized along with the mobilization of iron and was preliminarily concentrated in the“ Dachang Layer”.  相似文献   

13.
In northeastern Sanandaj-Sirjan structural zone, the Takab-Ghorveh belt comprises a volcanic province which related to the collision between the Eurasian and Arabian continents. It contains almost Quaternary andesitic basalt to alkali basalt. These alkali basaltes show Strombolian type eruptions. The volcanic rocks in Bijar area represent a range of mafic magmas, re-vealed by mingling and mixing textures. A variety of features suggest that the lava flows before eruption from magma chambers, contaminated by continental crust.  相似文献   

14.
Dielectric data for volcanic scoria and basalt on the earth at microwave frequency are extremely sparse, and also crucial for volcanic terrains imaging, and development. In consideration of their similarity to lunar regolith (soils and rocks) in chemical and mineral composition, the dielectric data is significative for passive and active microwave remote sensing on the Moon. This study provides the data about the dielectric properties of three kinds of scoria and two kinds of basalt in China. The method put forward in this paper is also applicable for measuring the dielectric properties of dry rocks and other granular ground materials with low complex dielectric constants. Firstly, the authors measured the ε‘ and tanδ values of strip specimens prepared from the mixture of scoria or basalt powder and polythene with the resonant cavity perturbation method at 9370 MHz. Secondly, from the ε‘ and tang values of the mixture, the ε‘s and tanδs values of sofid scoria and basalt were calculated using Lichtenecker‘s mixture formulae. Finally, the effective complex dielectric constants, ε‘e and tanδs, of scoria at different bulk densities were calculated. The results have shown that the ε‘s and tang svalues of all solid basaltic materials measured (both solid basaltic scoria or basalt) are approximately 7 and 0.05,respectively. With increasing bulk density of scoria, the ε‘s and tanδs values of scoria increase significantly.  相似文献   

15.
Fluid inclusions have recorded the history of degassing in basalt. Some fluid inclusions in olivine and pyroxene phenocrysts of basalt were analyzed by micro-thermometry and Raman spectroscopy in this paper. The experimental results showed that many inclusions are present almost in a pure CO2 system. The densities of some CO2 inclusions were computed in terms of Raman spectroscopic characteristics of CO2 Fermi resonance at room temperature. Their densities change over a wide range, but mainly between 0.044 g/cm3 and 0.289 g/cm3. Their micro-thermometric measurements showed that the CO2 inclusions examined reached homogenization between 1145.5℃ and 1265℃ . The mean value of homogenization temperatures of CO2 inclusions in basalts is near 1210℃. The trap pressures (depths) of inclusions were computed with the equation of state and computer program. Distribution of the trap depths makes it know that the degassing of magma can happen over a wide pressure (depth) range, but mainly at the depth of 0.48 km to 3.85 km. This implicates that basalt magma experienced intensive degassing and the CO2 gas reservoir from the basalt magma also may be formed in this range of depths. The results of this study showed that the depth of basalt magma degassing can be forecasted from CO2 fluid inclusions, and it is meaningful for understanding the process of magma degassing and constraining the inorganogenic CO2 gas reservoir.  相似文献   

16.
The occurrence,mineralogy and geochemistry of eclogites in the Mt.Dabie area show that they were subjected to a high-pressure metamorphism together with the country rocks,but their petrochemistry and REE geochemistry show some difference from those of the country rocks.The geochemical characteristics of the eclogites are similar to those of bot continental tholeiitic basalt and oceanic tholeiitic basalt.The rocks probably subducted to the upper mantle with the Dabie metamorphic complex.When elevated to the surface,they were subjected to different staes of retrogressive metamorphism.  相似文献   

17.
Presented in this paper are the trace element abundances of 16 samples of Hannuoba ultramafic inclusion-bearing aldali basalts,which were determined by instrumental neutron activation analysis and X-ray fluorescence spectrometry.The Petrogenesis of the alkali basalt suite has been modeled by batch partial melting and and Rayleigh fractional crystallization processes,The geochemical characteristics of the mantle source from where alkali basalts were derived are described in terms of variations in trace element abundances of the alkali basalt suite.  相似文献   

18.
南海玄武岩的某些地球化学特征   总被引:14,自引:1,他引:14  
Petrochemistry,geochronology,trace and REE geochemistry have been studied of a few basalts from the South China Sea.The results show that the South China Sen basalts may be divided into two types;alkali basalts and tholeiites.The former is similar to common alkali basalts in petrochemistry,REE distribution pattern and trace element geochemistry,but the latter is similar to Hawaiian tholeiites,belonging to the transition type between alkali basalt and MORB(mid-oceanic rise basalt).  相似文献   

19.
1 Introduction The native copper-chalcocite deposits associated with the Emeishan basalt have attracted great attention of many scientists engaged in ore deposits in recent years, but their focus is more put on the deposits hos- ted in the high-Ti basalt …  相似文献   

20.
Since continental sediments (in addition to the marine geological record) offer important means of deciphering environmental changes, the sediments hosted by the successive flows of the continental flood basalt provinces of the world should be treasure houses in gathering the palaeoclimatic data. Palaeosols developed on top of basalt flows are potentially ideal for palaeoenvironmental reconstructions because it is easy to determine their protolith geochemistry and also they define a definite time interval. The present paper summarizes the nature of the basalt-hosted palaeosols formed on the flood basalts provinces from different parts of the ~lobe havin~ different ages.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号