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131.
132.
基于Web的金刚石钻头模具钢体设计 总被引:3,自引:0,他引:3
介绍了应用网页技术进行金刚石钻头模具钢体设计计算的方法。该方法丰富了模具钢体设计的远程教育,免去了传统人工求解的繁杂过程,界面友好,精度高,结果可靠,具有实际使用价值。 相似文献
133.
Abstract In the first extensive, systematic study of inclusions in zircons from ultrahigh-pressure (UHP) and high-pressure (HP) metamorphic rocks of the Kokchetav Massif of Kazakhstan (separated from 232 rock samples from all representative lithologies and geographic regions), we identified graphite, quartz, garnet, phengite, phlogopite, rutile, albite, K-feldspar, amphibole, zoisite, kyanite, calcite, dolomite, apatite, monazite, omphacite and jadeite, as well as the diagnostic UHP metamorphic minerals (i.e. microdiamond and coesite) by laser Raman spectroscopy. In some instances, coesite + quartz and diamond + graphite occur together in a single rock sample, and inclusion aggregates also comprise polycrystalline diamond crystals overgrowing graphite. Secondary electron microscope and cathodoluminescence studies reveal that many zircons display distinct zonation textures, which comprise core and wide mantle, each with distinctive inclusion microassemblages. Pre-UHP metamorphic minerals such as graphite, quartz, phengite and apatite are common in the core, whereas diamond, coesite, garnet and jadeite occupy the mantle. The inclusions in core are irrelevant to the UHP metamorphism. The zircon core is of detrital or relatively low-grade metamorphic origin, whereas the mantle is of HP to UHP metamorphic origin. The zonal arrangement of inclusions and the presence of coesite and diamond without back-reaction imply that aqueous fluids were low to absent within the zircons during both prograde and retrograde metamorphism, and that the zircon preserves a prograde pressure–temperature record of the Kokchetav metamorphism which, elsewhere, has been more or less obliterated in the host rock. 相似文献
134.
Abstract High‐ to ultrahigh‐pressure metamorphic (HP–UHPM) rocks crop out over 150 km along an east–west axis in the Kokchetav Massif of northern Kazakhstan. They are disposed within the Massif as a 2 km thick, subhorizontal pile of sheet‐like nappes, predominantly composed of interlayered pelitic and psammitic schists and gneisses, amphibolite and orthogneiss, with discontinuous boudins and lenses of eclogite, dolomitic marble, whiteschist and garnet pyroxenite. On the basis of predominating lithologies, we subdivided the nappe group into four north‐dipping, fault‐bounded orogen‐parallel units (I–IV, from base to top). Constituent metabasic rocks exhibit a systematic progression of metamorphic grades, from high‐pressure amphibolite through quartz–eclogite and coesite–eclogite to diamond–eclogite facies. Coesite, diamond and other mineral inclusions within zircon offer the best means by which to clarify the regional extent of UHPM, as they are effectively sequestered from the effects of fluids during retrogression. Inclusion distribution and conventional geothermobarometric determinations demonstrate that the highest grade metamorphic rocks (Unit II: T = 780–1000°C, P = 37–60 kbar) are restricted to a medial position within the nappe group, and metamorphic grade decreases towards both the top (Unit III: T = 730–750°C, P = 11–14 kbar; Unit IV: T = 530°C, P = 7.5–9 kbar) and bottom (Unit I: T = 570–680°C; P = 7–13.5 kbar). Metamorphic zonal boundaries and internal structural fabrics are subhorizontal, and the latter exhibit opposing senses of shear at the bottom (top‐to‐the‐north) and top (top‐to‐the‐south) of the pile. The orogen‐scale architecture of the massif is sandwich‐like, with the HP–UHPM nappe group juxtaposed across large‐scale subhorizontal faults, against underlying low P–T metapelites (Daulet Suite) at the base, and overlying feebly metamorphosed clastic and carbonate rocks (Unit V). The available structural and petrologic data strongly suggest that the HP–UHPM rocks were extruded as a sequence of thin sheets, from a root zone in the south toward the foreland in the north, and juxtaposed into the adjacent lower‐grade units at shallow crustal levels of around 10 km. The nappe pile suffered considerable differential internal displacements, as the 2 km thick sequence contains rocks exhumed from depths of up to 200 km in the core, and around 30–40 km at the margins. Consequently, wedge extrusion, perhaps triggered by slab‐breakoff, is the most likely tectonic mechanism to exhume the Kokchetav HP–UHPM rocks. 相似文献
135.
136.
利用热液金刚石压腔研究了白云石在温度298 K、压力100~1 000 MPa下C-O键弯曲振动峰1ν097的拉曼变化特征。结果表明,在实验的压力范围内白云石稳定,其拉曼位移和压力具有很好的线性关系,拟合后得出压力与白云石1 097 cm-1拉曼线频率位移的关系为:p=143.47(Δpν)1 097+102.67(1 097
相似文献
137.
138.
金伯利岩中的镁铝榴石是寻找金刚石的重要指示矿物。镁铝榴石的Cr2O3、CaO等氧化物含量及其颜色、折光率等物理光学性质可作为这种石榴石的标型特征。 本文将山东、辽宁等地金伯利岩中的石榴石的电子探针分析结果按分子数配分的方法计算了端员分子百分数及其他化学参数。用MPV—1显微光度仪测定了石榴石的透射率色散值,通过计算求得颜色指数。按Dawson等人的分类,本次研究样品以铬镁铝榴石为主,其次是低钙-铬镁铝榴石、钙铬-镁铝榴石和镁铬-钙铬-镁铝榴石;钛镁铝榴石和钙镁铝-铁铝榴石等少量。作者用铬、钙、镁三组份数绘制了石榴石与金刚石关系判别图解,分为五个区(A、B、C、D、E)、落入A区的低钙-铬镁铝榴石、铬镁铝榴石和钙铬-镁铝榴石等与金刚石的形成关系最密切。 相似文献
139.
金刚石中的矿物包裹体 总被引:1,自引:0,他引:1
山东、辽宁金伯利岩区金刚石中的矿物包裹体是单晶相及多晶相的。大部分原生矿物包裹体为橄榄石,也有铬尖晶石、镁铝榴石、单斜辉石、斜方辉石、自然铁、针镍矿、柯石英、方解石及石墨。云母为后生包裹体矿物。橄榄石包裹体矿物富含Fo及Cr_2O_3。镁铝榴石矿物包裹体为紫红色,含Cr_2O_3,MgO及镁铬榴石分子高,形成压力为7.5GPa。单斜辉石包裹体矿物为绿色,形成温度和压力分别为:1531℃和4.5GPa。铬尖晶石包裹体矿物含Cr_2O_3及Cr/(Cr+Al)比值高,而含Al_2O_3低。柯石英的SiO_2含量为99.15%。自然铁含有少量的Co,Ni。针镍矿在金刚石中较常见。在橄榄石矿物包裹体内,见有方解石产出,其为同生矿物包裹体。 相似文献
140.
Xu Shutong Jiang Laili Liu Yican Zhang Yong Institute of Geological Sciences of Anhui Province Hefei Anhui Sun Sheping 《《地质学报》英文版》1992,66(3):221-238
The Dabie Mountains are believed to be a collisional orogenic belt between the Yangtze amd Sino-Koreancontinental plates. It is composed of the foreland fold-thrust zone, the subducting cover and basement of theYangtze continental plate, the coesite- and diamond-bearing ultra-high pressure metamorphic zone and themeta-ophiolitic melange zone in the subducting basement, the fore-arc flysch nappe and the back thrust zoneoccurring respectively on the southern and northern margins of the Sino-Korean continental plate and the in-herited basin with molassic deposits on the northern margin. When the palaeo-Dabie oceanic plate subductednorthward in the Early Palaeozoic, volcanic arc and back arc basin probably formed on the southern margin ofthe Sino-Korean continental plate. The Sm / Nd isotopic dating of the strata and eclogite which were drawn in-to the foreland fold-thrust zone indicates that the intense collision of the two continental plates took place inthe Early Mesozoic. 相似文献