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1.
分析了国务院《关于加强地质工作的决定》出台后,钻探技术面临的新形势;结合《国家中长期科学和技术发展规划纲要(2006~2020年)》对能源、水和矿产资源勘探开发、环境保护以及天然气水合物勘探开发技术的重视,分析了钻探技术面临的新机遇和新任务。最后提出了我国钻探技术研究发展的新目标。  相似文献   

2.
Native Australian Apoidea belong to six families with about 3000 species. In contrast the native New Zealand (NZ) Apoidea consists of 2 families, 4 genera and about 40 species, and that of New Caledonia (NC) of 3 families, 10 genera and 28 species. The sub-family Euryglossinae is newly recorded from NC. New Zealand's bee fauna is dominated by the Colletidae with about 36 species, while Halictidae are represented by 4 species. New Caledonia has 15 species of Halictidae but only 5 species of Colletidae. Megachilidae are absent from NZ but are represented by 8 species in NC, and their origin is probably from the north.The closet relatives of the NZ and NC Colletidae and Halictidae are Australian. Relationships within the bee fauna of NZ and NC suggest that the two faunas were derived from a few immigrations from Australia followed by speciation, rather than representing a vicariant event which would have resulted in distinct apomorphy in each region.The differential radiation of the Colletidae and Halictidae in NZ and NC probably reflects the interactions between the different biologies of the 2 bee families, and the markedly divergent geomorphology, soil structure, climate and floral phenology of the two areas.  相似文献   

3.
徐翀  李立平  杨春 《地质科学译丛》2010,(1):50-54,I0002
目前,普通、低品质的淡水珍珠产品已无法满足大部分消费者的时尚需求,但随着珍珠养殖技术与加工技术的进一步发展,市场上出现了许多新的珍珠品种。系统地总结了目前中国珍珠市场上新造型的珍珠的特征,其中有核珍珠更适合于加工成各式各样的异形珠。以淡水无核珍珠为对象,重点探讨了刻面加工技术、镶嵌技术和雕刻技术在改善珍珠外观方面的应用,进一步分析了刻面珍珠的琢磨角度与时间;对椭圆形珍珠、腰线珍珠进行CZ镶嵌,使其外观得到了改善,提升了其价值。最后,对珍珠的雕刻技术进行了初步探讨。  相似文献   

4.
为了进一步落实中国地质科学院工作会议精神,推动地质力学研究所的体制改革工作,我就当前全院体制改革的情况,以《新形势、新对策》为题作一个演讲。我要讲5个问题:新形势,新机遇,新困难,新挑战和新对策。   相似文献   

5.
The environment has, ins a regional sense, the function of usefulness and the function of housing both being very often contradictory. The prospects of New Towns reduce the occurrence of such conflicts and bring some possibilities for applied-geography-intervention. In the densely populated countries of Central Europe mining, manufacturing, administrative and regional utilization are the main decisive functions in the developing for the origin, localization and prosperity of New Towns.  相似文献   

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The environment has, ins a regional sense, the function of usefulness and the function of housing both being very often contradictory. The prospects of New Towns reduce the occurrence of such conflicts and bring some possibilities for applied-geography-intervention. In the densely populated countries of Central Europe mining, manufacturing, administrative and regional utilization are the main decisive functions in the developing for the origin, localization and prosperity of New Towns.  相似文献   

10.
We treat the ocean carbon cycle as a coupled physical-biogeochemical process. The interactions between mixed-layer dynamics and growth of phytoplankton in the layer are discussed, and the formal relationship between phytoplankton accumulation and new production is examined. A coupled biological-physical model is presented for studying the classical spring bloom in the N. Atlantic, and possible differences in the mechanisms that drive the seasonal phytoplankton blooms in the N. Atlantic and the Arabian Sea are discussed. Finally, recommendations are made for observational programs to improve our understanding of the biologically-mediated carbon cycle in the Arabian Sea.  相似文献   

11.
最近十多年来,国际稀有气体同位素地球化学研究紧随地球科学的发展态势,开始涉入一些新的研究领域,特别是在地下水、极地和高原冰雪、海洋和湖泊沉积等非常规领域,研究内容涵盖了水源示踪、地下水测年、气候变化、岩石暴露年龄、岩石剥蚀速率等问题。这些新动向值得国内同行及早予以关注,同时应及时跟进和发展,以尽快与国际同一研究领域接轨。  相似文献   

12.
Aromatic hydrocarbons from benzene extracts of New Albany Shale were characterized. A biomarker that has a molecular weight of 546 and a structural configuration consistent with that of an alkyl-aromatic hydrocarbon (C40H66) was tentatively identified. It was found that the relative concentrations of the biomarker are indicative of differing levels of thermal maturity of the shale organic matter. A 40-carbon bicyclic carotenoid (C40H48) is proposed as the geochemical precursor of this biomarker. Thermal maturity of the shale organic matter can also be differentiated by observing differences in “fingerprints” as obtained by field-ionization mass spectrometry on the aromatic hydrocarbon fraction. Using this technique, we found that the more mature shale samples from southeastern Illinois contain more low molecular weight extractable aromatic hydrocarbons and the less mature shale samples from northwestern Illinois contain more high molecular weight extractable aromatic hydrocarbons. It was demonstrated that field-ionization and tandem mass spectrometric techniques through fingerprint and individual compound identification, are useful for shale aromatic hydrocarbon fraction characterization and for thermal maturation interpretation.  相似文献   

13.
研究与寻找新的油气资源、开拓勘探新领域   总被引:4,自引:0,他引:4  
天然气将成为人类第四代能源。非常规天然气资源量比常规天然气的资源量多一个量级以上。研究非常规天然气理论,开拓勘探新领域将为人类提供丰富的天然气资源。中国在非生物成因天然气、深层石油天然气和煤层等非常规天然气研究和勘探方面均取得重要进展,对改变能源结构,满足未来发展对能源的需求将会有重要战略意义。天然气的长距离传输要求储量在1000亿m^3以上,以确保满足生产量为300-500万m^3的输气量,维持30年以上,可获得较大的经济效益和社会效益。  相似文献   

14.
The traditional Bangongco-Nujiang metallogenic belt overlap with the ophiolitic melange units remained in the Bangongco-Nujiang ocean including the Cr, Au, Fe mineralization controlled with magma liquation. On the other hand, the broad metallogenic belt involved the deposits which had been recognized the products of subduction or postsubduction lithospheric extension in the northern and southern sides of Bangongco-Nujiang subduction zone, which includes the southern edge of the southern Qiangtang, suture zone, part of the North and Middle Gangdese block. The types of deposits include porphyry copper (gold) deposits, skarn iron (copper) deposits, hydrothermal-altered rock type of gold deposits and hydrothermal type of tungsten deposits throughout the evolution of Bangongco-Nujiang ocean. The copper mineralization has two episodes at about 120~105 Ma and 90~85 Ma, respectively. The early stage of copper mineralization (120~105 Ma) likely formes by remelting of previously subduction-modified arc lithosphere. Moreover, the late stage of copper mineralization (90~85 Ma) could be triggered by postcollisional lithospheric mantle delamination. Some of key fundamental scientific problems, such as Tectonic background (metallogenic environment), magmatism, metallogenic mechanism of typical deposits, the relationship between the preservation and plateau uplift, we need to pay attention to in the future work.  相似文献   

15.
In 1974 the author preliminarily reported two new platinum group minerals-daomanite and hongshiite. The two minerals were accepted by the Commission on New Minerals and Minerals Names of the International Mineralogical Association in 1976 and 1982 respectively. Because of the conditions at that time, the work was preliminary, for example, there were only reflectance values of four wave bands. Recently the author again made measurements of reflectances, corrected cell parameters by the four-circle diffractometer and electron diffraction and supplemented their new occurrences and nomenclature.  相似文献   

16.
改革开放以来,武建集团坚持以市场为取向,与时俱进,大胆探索,不断深化企业改革,优化企业结构,转换企业体制和机制,创新企业管理,推动了企业持续发展,在集团信誉、工程质量、经营领域和地域的开拓等方面不断取得了新的进步。下面就武建集团的改革和我们的体会向大家作一汇报。  相似文献   

17.
The Reading Prong is part of the Precambrian basement whichis discontinuously exposed in the north-central Appalachians.Precambrian rocks in the northeastern Prong consist of diversegneisses which were plastically deformed, metmorphosed to thehornblende granulite facies, and intruded by syntectonic granitesaround 1150 m.y. ago. Sillimanite-garnet-biotite-quartz-two feldspar paragneisses(locally with hornblende or cordierite and without sillimanite)are one of the predominate lithologies in this area. Micro-probeand wet chemical analyses show biotites from these assemblageshave variable Fe/Mg mol. ratios (3.5–0.3) and containappreciable Ti and A1. The biotites are not zoned with respectto Fe or Mg (except for a systematic decrease in the Fe/Mg ratioin rims contiguous with garnet), however Ti is typically depletedin rim compositions with a reciprocal increase of octahedralA1. Garnets are principally solutions of almandine and pyrope(Fe/Mg mol. ratio, 13.1–1.2) with minor grossularite andspessartine components. They are compositionally zoned, withFe concentrated in rims and Mg in cores (particularly wherethey are contiguous with biotite). The analyzed garnets arehomogeneous with respect to Ca and Mn. The most iron-rich biotitesand garnets are found associated with hornblende. The partitioning of Fe and Mg between the interiors of coexistinggarnet and biotite is uniform within each locality sampled.Although the partitioning is variable on a regional scale, thisappears to reflect the non-ideality of the distribution (a resultof the large and variable octahedral Ti and A1 concentrationsin biotite) and not any major, systematic variations in progrademetamorphic conditions. Low temperature alteration of these prograde assemblages issporadically present in paragneisses west of the Hudson Riverand includes associations of: phengitic muscovite, epidote,clinozoisite, chlorite, and secondary calcite. Isotopic agedata (Sutter & Dallmeyer, 1972) suggest slow uplift of thissegment of the Reading Prong, and it appears that these alterationfeatures developed as a result of prolonged cooling followingthe 1150 m.y. metamorphism. In an attempt to re-equilibrateto the lower temperature conditions during uplift, localizedexchange of Fe and Mg occurred between contiguous garnet andbiotite. Alteration is more widespread in the easternmost paragneisseswhere textural, chemical, and isotopic data suggest these secondaryfeatures are, in part, a result of retrograde metamorphism duringone or more Paleozoic orogenic events recorded in the surroundingterrain.  相似文献   

18.
通过对预制分支电缆,只报警不脱扣的漏电断路器、三相应急电源(EPS)和低压电涌保护器(SPD)的工作原理及性能、特点的介绍,说明了这些新产品、新技术为设计人员优化设计、使现代建筑更安全、更自动化、更可靠创造了条件。  相似文献   

19.
New Pb-, Sr-, and Nd-isotopic data have been obtained for the rocks of volcanoes overlying a wide range of depths (100–580 km) to the Wadati-Benioff Zone (WBZ) in the New Britain island arc, Papua New Guinea. Well-defined trends consistent with two-component mixing are observed in combined Pb-isotope/trace-element plots. One of the components is believed to represent a slab contribution whose isotopic signature, unlike those noted for several other arcs, appears to be dominated by subducted, altered, oceanic crust rather than by sediment. This conclusion is consistent with the results of a recent Be–B study of New Britain rocks. The influence of the slab component is considered to decrease as depth to the WBZ increases. Higher abundances of high-field-strength elements correlate with increasing depths to the WBZ, and may be indicative of smaller degrees of partial melting of the mantle wedge as WBZ depths increase. Abundances of other incompatible elements appear to reflect a complex interplay between the slab-derived flux and melting process.  相似文献   

20.
Applying the methods of absolute geochronology and lithology, it has been established that the average sedimentation rate in the Sea of Azov over the last 6000 years (Ancient and New Azov times) varied from 0.2 to 2.0 mm/year. Its minimum values are confined to transit and sediment-starved zones coinciding with the directions of the main marine currents. It has been indicated that changes in the water level of the Sea of Azov occur with lag relative to landscape–climate phases. The obtained data confirm the relation between marine and terrestrial processes occurring in the Sea of Azov region: transgressive phases are preceded by general humidification in adjacent regions, while regressive phases correlate with climate aridization. The biostratigraphic analysis of the Holocene sections examined reveals the unstable behavior of the sea level during their formation. The results of diatom analysis confirm development of the Phanagoria and Korsun Regressions and Nymphea Transgression. Frequent fluctuations of the Sea of Azov the level determined the rhythmical structure of the sedimentary sequence saturated with autochthonous and allochthonous organic matter.  相似文献   

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