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51.
采用环境扫描电子显微镜(配置能谱仪)对3件靖安古玉器样品的表面微结构及微形貌特征、主要化学成分进行了观察与测试,结果表明,样品均为透闪石质软玉,其外观特征与结构有一定关系。样品G47具有亚透明这一罕见、不同于软玉的外观特征,其透闪石的质量分数最高,晶体较粗大,定向排列,为显微柱状变晶结构;样品G36具典型的油脂光泽、半透明外观特征,其透闪石晶体细小、紧密交织,为显微纤维交织变晶结构;样品G21中受沁较轻的灰白色部分的结构较疏松,有孔洞,其透闪石晶体呈细长纤维状,结晶程度低,为显微纤维一隐晶质变晶结构,受沁较严重的褐色部分则表现为显微粒状微形貌特征。  相似文献   
52.
微裂隙对于岩石的物理性质有重要影响.通过光学显微镜对显微裂隙进行的观察,难以将薄片的制作过程中产生的裂隙同自然裂隙区分;其次,观测的裂隙大小限制在0.1mm或以上数量级,一些重要细节观察不到.扫描电镜的高放大倍数和三维分辨率使其成为适合于裂隙研究的理想工具.利用扫描电镜观测了浙江花岗岩在室温下由51.6MPa压力产生的裂隙的发育过程.观察花岗岩的表面以研究其微裂隙和矿物的解理、晶形及破裂作用.微裂隙分为3种类型:晶体内裂隙(完全发育在颗粒内部),晶体间裂隙(穿过颗粒边界进入其他颗粒中),颗粒边界裂隙(沿颗粒边界发育或与边界重合).本研究中的花岗岩为中-粗粒(1~6mm),经过蚀变,约含40%斜长石,25%钾长石,25%石英,10%镁铁矿物(主要为黑云母和白云母).  相似文献   
53.
因为取样时未使用保温保压工具,所以通常情况下采集到的天然气水合物样品在被放入液氮罐冷藏之前,必定已经发生了部分分解;具有代表性意义的ODP 204取得的样品85%分解了,且转变成六方晶体冰。因此,分析描述天然气水合物分解的状况、外观和特征十分必要。综述了利用可确定天然气水合物中冰、水合物和其他矿物相对数量以阐明其保存程度的同步加速X光衍射(XRD)技术和可在低至几十纳米分辨率条件下对样品进行详细观测的低温扫描电镜技术进行非保真采取水合物样品外观和保存状况研究的概况,包括Ⅰ型结构水合物及孔隙横截面均为六边形和亚微米级孔隙区域到密集孔隙区域特征等成果,指出取心时水合物分解耗热,是吸热反应并导致分解释放水同步冻结;同时气体膨胀和气体脱溶也形成冰;这类样品中天然气水合物周围小区域内温度很低并在局部成冰,水合物实现自我保存,这一特性允许天然气水合物在稳定正常的温压条件以外存在一段时间,对于天然气水合物商业储运具有重要意义,但是,多数情况下水合物还是分解了。在“水合物海脊”,样品含天然气水合物量仅少数超过15%,极少数达到70%,只有在原位状态为大块状的天然气水合物中,才可以用肉眼观察到高含量的天然气水合物组分。  相似文献   
54.
采用分析电子显微镜法对采自太平洋陆架沉积层和海底山脉不同时代和不同成分的磷块岩的研究表明,在其中存在着超显微颗粒的自生铀矿物,在稀少的情况下还有自生的稀土元素矿物。在一系列来自纳米比亚陆架的上新一更新世磷块岩标本中发现了这两种类型的矿物。铀矿物是沥青铀矿、科芬矿和磷钙铀矿;稀土元素矿物为独居石、磷钇矿和氟铈矿,这证明它们不仅可能以类质同像混入物的形态存在于钙的磷酸盐中,还能以独立矿物相的形态存在。  相似文献   
55.
56.
杜谷  杨波 《岩矿测试》2012,31(1):199-199
1检测中心历史沿革国土资源部西南矿产资源监督检测中心,前身为原地质矿产部成都地质矿产研究所实验分析测试中心,现隶属于中国地质调查局成都地质调查中心。实验室始建于1964年,经过近50年的发展,已经成为岩石矿物分析综合性专业实验检测机构,在我国西南地区的基础地质调查与研究、地球化学找矿、环境地球化学评价中充分发挥了技术支撑作用。实验室在1992年通过国家级计量认证,2006年经国土资源部授权挂牌成立国土资源部西南矿产资源监督检测  相似文献   
57.
卵巢癌的卵巢癌伴浆液癌中常提示有较好明砂粒体矿化灶的矿物砂粒体泽,最常见液性乳头状化机制尚不难性导致国择浆液性卵象,利用偏射电子显微对砂粒体矿研究。从北京显砂粒体矿Leica超薄于普通载(Nikon L20mm×20显微镜(Q是女性生殖有钙化(刘见砂粒体钙生存的预后化与癌变之学特征进行呈粒状,常于甲状腺乳囊腺癌中明确,样品内外研究都  相似文献   
58.
We performed ion irradiation on olivine and ilmenite to simulate solar-wind exposure effects in lunar soil. The surface morphology and microstructure after ion irradiation were characterized by field emission scanning electron microscopy. Sputtering erosion significantly modified the surface of irradiated Luobusha olivine grains. All irradiated grains show smooth surface and round shape. The cleavage fractures on the unirradiated olivine surface were widened and deeply etched after He+ irradiation. Both of these are the consequence of ion sputtering erosion. There are no bubbles or voids foundin the irradiated olivine grains, because He+ dose in this study is lower than saturated fluence. Irradiated Panzhihua ilmenite grains are all covered with smooth flakes with the thickness of about 400 nm. The formation of the flakes should be related with helium bubbles and their growth during He+ implantation. Some columnar-shaped particles are found at the surface of irradiated Panzhihua ilmenite. We speculate that these particles should be sulfide because of significantly high sulfur contents.  相似文献   
59.
This study collected the early Oligocene to middle Miocene sediments from the Gerze Basin of Tibet, and used X-Ray diffraction (XRD) and Scanning Electron Microscope (SEM) to discuss their clay mineralolgy, clay indices, better understand the clay mineralogy and its paleoclimatic significance. The results show that clay minerals of the Gerze Basin sediments are mainly composed of iilite and chlorite, with minor amounts of smectite and kaolinite, and their relative content varies along the section. Variations of relative contents and clay indices suggest that the Gerze Basin has experienced three-stage evolution of paleoclimate: I ) high ilUte and chlorite contents, with fluctuant smectite and low (I+Ch)/(K+S) ratio, indicative of a dominant seasonal arid climate from the early Oligoeene to late Oligocene; Ⅱ) higher illite and chlorite contents and larger (I+Ch)/(K+S) ratio but absence of kaolinite, indicating a colder and drier climate from the late Oligocene to early Miocene; Ⅲ) high iilite and chlorite contents with fluctuant (I+Ch)/(K+S) ratios and occasional occurrence of kaolinite, suggesting that the climate became warmer and more humid compared with that of stage Ⅱ in the mid-Miocene. These conclusions were also reinforced by the clay morphology, which suggests that physical weathering dominated in stage Ⅱ, while relatively strong chemical weathering was dominant in stages Ⅰ and Ⅲ Clay minerals of the sediments mainly consist of illite and chlorite, indicating that the source rock played a significant role in clay origin. It is inferred that global cooling and the enhancement of denudation and obstruction of northward moisture due to the uplift of the Qinghai-Tibet Plateau were responsible for the provenance of iUite and chlorite under weak chemical weathering. Though the Qinghai-Tibet Plateau reached a certain elevation by the mid-Miocene, yet the mid-Miocene widespread warming might have largely impacted the Gerze climate.  相似文献   
60.
In order to determine the genesis and the factors that control the low-porosity and low- permeability sandstone reservoirs in the eastern Sulige Gas Field in the Ordos Basin, systematic studies on the sedimentary facies and diagenesis were conducted by means of analysis of cores, thin sections, fluid inclusions, X-ray diffraction, cathode luminescence and scanning electron microscope. It was found that the sand bodies of the major gas reservoirs in the Shan1 section (P1S1) and the He8 section (P2H8) were formed during the Permian as sedimentary facies such as braided-channel bars, braided-river channels and point bars of a meandering river. Four types of diagenetic facies developed subsequently: in order from the best to the poorest properties these are type A (weak compaction, early calcite cement-chlorite film facies), type B (moderate compaction, quartz overgrowth-feldspar corrosion-kaolinite filling facies), type C (strong compaction, late calcite cement-quartz corrosion facies) and type D (matrix filling and strong compaction facies). This diagenesis is undoubtedly the main reason for the poor reservoir properties of sandstone reservoirs, but the sedimentary facies are the underlying factors that greatly affect the diagenesis and thus the reservoir performance. Favorable diagenetic facies developed mainly in relatively small lithofacies such as braided-river channels, channel bars and point bars. The vertical distribution of the physical properties and the diagenetic facies of the reservoirs are related to the stratigraphic succession. Most of the sandstones between mudstones and thin beds of sandstone are unfavorable diagenetic facies. Analyses indicate that siliceous cementation can hardly be stopped by hydrocarbon filling. Authigenic chlorite could hardly protect the primary porosity. It not only occupies pore space, but also blocks pathways through sandstone reservoirs, so that it has significant influence on the permeability. Authigenic chlorite cannot be used as a marker for a  相似文献   
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