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1.
大庙矿产在石榴石角闪石辉石岩中的含钴、铜的铂矿脉中。它常呈直径为1.0—2.0mm的小圆球与伊逊矿紧密共生;不透明,金属光泽;颜色为钢灰色,条痕黑色;莫氏硬度H_M 5.3,显微硬度VHN_(50) 485 kg/mm~2(范围434—529 kg/mm~2);无解理;计算密度D_(calc.) =10.95 g/cm~3。9个电子探针分析的平均化学成分为(％):Pt 45.6,In 53.5。化学式为:PtIn_2。6条最强X射线衍射线(hkl,d,I)为:220,2.25(100);311,1.92(60);400,1.59(60);422,1.299(80);440,1.125(60);620,1.006(70)。X射线粉晶衍射线图谱指标化后求得该矿物为等轴晶系,空间群:Fm3m。α=0.6364(3)nm。V=0.25775nm~3。Z=4。 相似文献
2.
伊逊矿产在石榴石角闪石辉石岩的含钴、铜的铂矿脉中,常呈直径为1.0—2.0mm的小圆球,与大庙矿紧密连晶。伊逊矿为不透明,金属光泽;颜色钢灰色.条痕黑色;莫氏硬度H_M=5.8,显微硬度VHN_(50)=634kg/mm~2;均质性,无解理;计算密度D_(calc.)=18.219/cm~2。8个电子探针分析的平均化学成分(％)为:Pt 82.8(81.8—83.6)、In 16.4(l5.6—17.1)。化学式为:Pt_3In。5条最强X射线衍射线(hkl,d,I)为:111,2.30(100);200,1.99(60);202,1.411(40);311,1.203(80);222,1.151(40)。X射线粉晶衍射线指标化后,求得该矿物为等轴晶系。空间群:Pm3m。α=0.3988(3)nm,V=0.06343nm~3,Z=1。 相似文献
3.
一维非公度调制结构安康矿X射线衍射及四维空间指标化研究 总被引：1，自引：0，他引：1
采用最新的CCD单晶衍射仪,对一维非公度调制结构矿物安康矿进行了单晶和粉晶X射线衍射研究,利用单晶X射线衍射和三维超结构分析方法测定晶胞参数a=1.014 08(10)nm,b=1.014 08(10)nm,c=0.295 72(6)nm,α=90,°=β90,°γ=90,°调制向量q=0.444c*,据此对单晶衍射数据进行了四维空间的指标化。并用新近研究开发的利用单晶体来进行粉晶衍射的新方法对粉晶衍射实验及粉晶数据的四维空间进行指标化研究。 相似文献
4.
我国几个矿区叶蜡石X射线粉晶衍射研究 总被引：4，自引：0，他引：4
对我国几个主要类型叶蜡石矿的叶蜡石做了X射线粉晶衍射研究。从大量实验结果发现,所研究叶蜡石存在单斜晶系和三斜晶系两种多型。单斜晶系(2M);空间群G_(2h)~6-C2/c,a=5.175A,b=8.902A,c=18.673A,β=100.1°,Z=4;三斜晶系(1Tc):空间群P_c,a=5.162A,b=8.965A,c=9.346A,a=91.2°,β=99.96°,γ=89.91°,Z=2。 相似文献
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6.
新矿物产于云南盈江县的一个铀矿点氧化带,与多种铀矿物共生。该矿物为致密状集合体,黄色,透明至半透明。斜方晶系,空间群C222_1,晶胞参数a=13.73(1),b=15.99(1),c=17.33(2);V=3804(5);Z=8。计算比重4.17。二轴晶负光性,2V计算=83°,α=1.669;β=1.692;γ=1.710。紫外光照射发弱绿黄色荧光。化学成分UO_376.54,P_2O_511.10,K_2O 2.46,CaO 1.57,ThO 0.51,RE_2O_3 0.45,H_2O 7.37%。矿物化学式为(K_(1-x),Ca_x)(UO_2)_3 (PO_4)_2 (OH)_(1+x)·4H_2O,文中还给出X射线粉晶衍射数据。 相似文献
7.
纤钡锂石产于湖南临武香花岭地区一水晶矿锂云母石英脉晶洞中,与锂云母、石英等矿物共生。矿物为浅黄白色,丝绢光泽,呈针状、纤维状、放射状或平行束状集合体,纤维长达1厘米。经X射线单晶及粉晶衍射测定:该矿物属斜方晶系,空间群Ccca,晶胞参数:a=13.60(?),b=20.24(?),e=5.16(?)。最强衍射线为:10.12(?)(100) 4.05(?)(78) 3.39(?)(91) 2.605(?)(31)2.390(?)(28)。 相似文献
8.
钴硅锌矿是一种具有特征深蓝紫色、油脂光泽和玻璃光泽的钴锌硅酸盐矿物,属三方晶系。空间群:C_(3j)~2—R3、a=13.9559A,c=9.3364A,c/a=0.6690,V=1574.8104A~3,Z=18。该矿物理论式为(Zn,Co)_2SiO_4,实验式为:(Zn_(1.26),Co_(O.74))SiO_4。据红外光谱以及X射线粉晶分析,其结构与硅锌矿(Zn_2SiO_4)类似。 相似文献
9.
未定名矿物(Bi38CrO60)的矿物学研究 总被引：2，自引：0，他引：2
人工合成立方晶体Bi38CrO60在自然界首次发现于中国陕西省洛南县驾鹿金矿床中,暂称之为未定名矿物.其共生和伴生矿物有黄铁矿、自然金、碲金矿、含氧金矿物等.常呈不规则粒状集合体,偶见立方体微晶(粒径小于0.05 mm),棕黑色,金属光泽;HV=232.78 kg/mm2 ,HM=4.15;D=14.10(3)g/cm3,Dx=14.08(2)g/cm3,n=3.14(3).EPM8100探针分析Bi2O3为98.854%、CrO3为1.111%,合计99.965%,化学式为Bi38.009Cr0.995O60;CAMEBAX-SX51探针分析Bi2O3为98.862%,CrO3为1.112%,合计99.974%,化学式为Bi38.008Cr0.996O60.均可写为Bi38CrO60.X射线粉晶分析主要强度线d(I)(hkl)分别为0.321 5(100),(310);0.272 11(72),(321);0.171 45(40),(530);0.169 6(30),(600);0.165 1(30),(611);0.160 8(30),(620);0.294 11(25),(222);0.359 6(22),(220);0.217 1(20),(332);0.150 3(20),(631),等轴晶系,可能的空间群为Im3m;a=1.018 1(1)nm,c/a=1,晶胞体积v=1.055 29(1)nm3,z=1.1-Kp/Kc=0.019.Cr6 ,Bi3 ,O2-.未定名矿物和人工晶体的化学成分与X射线粉晶数据基本一致. 相似文献
10.
在西藏罗布莎蛇绿岩块的铬铁矿中，存在一种Fe—Cr—Ni合金，电子探针分析确定其化学分子式为Ni0.45 Cr0．29 Fe0．26。其x射线粉晶衍射数据(括号内为I／Io，hkl)为：2．060(100，111)、1．775(70，200)、1．261(60，220)、1．076(50，311)、1．027(50，222)，晶体结构应属于金属元素的γ—Fe物相。按其所属空间群金属元素的排列方式，确定其原子坐标并计算了理论粉晶衍射图，结果表明，理论粉晶图谱与实测粉晶衍射数据基本一致。该Fe—Cr—Ni合金晶体学参数可归纳为：a＝3．5622A，空间群Fm3m，单位晶胞中的分子数Z＝4，Dc＝8．212g/cm^3。 相似文献
11.
新疆不同区域牧业雪灾损失时频变化特征 总被引：2，自引：2，他引：0
选用新疆1952-2013年75个县707条雪灾害资料, 采用灰色关联评估模型以县为单位将新疆分为特重雪灾区、 重雪灾区、 一般雪灾区、 小雪灾区. 用气候趋势系数与五阶函数分析各雪灾区牲畜死亡数额的长期变化趋势, 并用morlet小波分析其振荡周期. 结果表明: 全疆及各雪灾区牲畜死亡数额基本都存在23 a左右的长周期, 14～17 a中周期, 10 a左右的小周期, 另外, 还存在5～7 a的小波动, 各区周期振荡的强弱及时间范围不同. 全疆及特重雪灾区牲畜死亡数额长期以来有减少趋势; 而重雪灾区和一般雪灾区牲畜死亡数额长期以来有微弱的增加趋势. 特重雪灾区牲畜死亡数额长期变化趋势决定了新疆雪灾牲畜死亡数额的长期变化趋势, 全疆平均每年因雪灾牲畜死亡数额以0.4%的速率递减, 特重雪灾区每年按上一年度总额1.4%的速率递减. 由于20世纪80年代开始, 新疆有计划、 大规模推行牧民定居工程, 从而大大提高了新疆牧业抗御自然灾害的能力, 以及冬春气温升高的缘故, 使得全疆及各雪灾区牲畜死亡数额大大减少. 因为各牧业区实施牧民定居工程开始的时间不同, 使全疆各雪灾区牲畜死亡数额高值期(年代际与年际尺度振荡的活跃期)进入低值期(少发时期)的临界时间存在差异. 相似文献
12.
重力场定义的澄清 总被引：3，自引：1，他引：2
《朗曼现代英文词典》(LongmanModernEnglishDictionary)、《牛津高阶英汉双解词典》(OxfordAdvancedLearner’sEnglish ChineseDictionary)、《韦氏词典》(Merriam Webster’sNewCollegiateDictionary)、作为地球物理专业词汇定义源的《勘探地球物理百科词典》(EncyclopedicDictionaryofExplorationGeo physics)以及中国的一些重力教科书、专著及词典 ,把重力场定义为重力或重力作用存在的空间 ,重力效应可以测量的空间 ,即 :力或重力存在的空间。这个定义不同于国外英文地球物理教科书、专著及中、英、俄文场论教科书对重力场的定义 :空间中的重力。定义重力场为重力存在的空间 ,混淆了“场”本身及“场域”的概念 ,并不是一个标准的物理或地球物理定义 ,是一种误导。物理场是空间中存在的一种物理作用或效应 ,分布于引起它的场源体周围。两个物体之间存在着的相互作用力 ,通过每个物体引起的引力场给予另一个物体。重力场可以定义如下 :地球内部及其附近空间一点处存在的重力作用 ,或单位质量受到的重力。重力场是一种力或力场 ,存在于地球表面及其附近的空间。重力场不是空间 ,重力场的测量应当是在重力场存在的空间或场域中 ,而不是在重力场中进行。 相似文献
13.
Planform evolution of deltas with graded alluvial topsets: Insights from three‐dimensional tank experiments,geometric considerations and field applications 
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下载免费PDF全文 Tetsuji Muto Ryuji Furubayashi Arti Tomer Tomoyuki Sato Wonsuck Kim Hajime Naruse Gary Parker 《Sedimentology》2016,63(7):2158-2189
The profile of a river that conveys sediment without net deposition and net erosion is referred to as ‘graded’ with respect to vertical aggradation of the river segment. Three experimental series, designed in terms of the autostratigraphic view of alluvial grade, were conducted to clarify the diagnostic spatial behaviour of graded alluvial–deltaic rivers: an ‘R series’, which utilized a moving boundary setting with a stationary base level; an ‘F series’ in a fixed boundary setting with a stationary base level to produce ‘forced grade’; and an ‘M series’ in a moving boundary setting with constant base‐level fall to produce ‘autogenic grade.’ The results of the three experimental series, combined with geometrical modelling of the effects of basin water depth and other experimental data, suggest the following: (i) in a graded alluvial–deltaic system, lateral shifting and avulsing of active distributary channels are suppressed regardless of whether the downstream boundary of the deltaic system is fixed; (ii) in a delta with a downstream‐fixed boundary, the graded streams are stabilized within a valley that is incised in the axial part of the delta plain, whereby the alluvial plain outside the valley is abandoned and terraced; (iii) in moving boundary settings, the graded river simply extends basinward as a linearly elongated channel and lobe system without cutting a valley; and (iv) a modern forced‐graded alluvial river is most likely to be found in a valley incised into a fan delta in front of very deep water, and the stratigraphic signal of fossil autogenic‐graded rivers will be found in deltaic successions that accumulated in the outer to marginal areas of deltaic continental shelves during sea‐level falls. This renewed autostratigraphic view of alluvial grade suggests a thorough reconsideration of the conventional understanding that an alluvial river feeding a progradational delta is graded with a stationary base level. 相似文献
14.
The Southern Ocean is a strong sink for atmospheric CO2, making it especially vulnerable to ocean acidification (OA). The aragonite saturation state (Ωarg) of seawater has been used as an index for the estimation of OA, which plays a critical role in evaluating the living environment of marine calcified organisms. However, it is very difficult to perform the studies of OA and Ωarg in the Southern Ocean due to its harsh climate. Therefore, in order to better understand the OA and its further influences, the advances of Ωarg studies were summarized in the oceans surrounding the Antarctica. Significant spatial and temporal variations of surface seawater Ωarg are demonstrated in the Southern Ocean. In general, the surface seawater Ωarg shows a lower value in the off-shore areas than in the open oceans. And, Ωarg also exhibits a strong seasonal cycle with a higher value in summer than in winter. The distributions of Ωarg in vertical water column generally present a declining tendency from surface to bottom. In addition, the shoaling of Ωarg horizon at high latitude could be attributed to the ventilation and upwelling of deep waters in the Southern Ocean. There are many factors that could impact the Ωarg in the Southern Ocean, including sea ice melting, sea-air CO2 exchange, biological activities and hydrological processes, etc. Finally, the future changes and key scientific problems of OA in the Southern Ocean are proposed. 相似文献
15.
A foreland basin succession has been identified in the Frasnian of the Central Pyrenees. This succession comprises a carbonate-dominated transgressive system which recorded the cratonward migration of the foreland basin subsidence, and siliciclastic depocenters which recorded the progression of the thrust-fold deformation. The foreland basin system has always been maintained in deep-marine environments, i.e., at an underfilled depositional state. It was associated with a thrust wedge which descended toward a deep-marine hinterland, i.e., with a type of orogenic wedge usually related to subduction zones. The Frasnian foreland basin system differs from the one known in the Carboniferous which evolved to overfilled depositional state and was associated with a thrust wedge rising toward a mountainous hinterland. Consequently, the Hercynian orogeny in the Pyrenees seems to result first, from a Frasnian thrusting controlled by a subduction zone located north of the Pyrenees, and second, from a Carboniferous thrusting controlled by the surrection of a frontal thrust belt in the Pyrenees. The association of underfilled foreland basin systems and hinterland-dipping thrust wedges, as exemplified in the Frasnian of the Pyrenees, can be interpreted as illustrative of the initial stages of thrust-wedge growth in deep-marine settings. 相似文献
16.
对造山带古地理学在盆地构造——古地理重建中的若干思考 总被引：8，自引：3，他引：8
造山带古地理学在盆地构造--古地理重建中的若干思考的核心，是以活动论的构造观指导盆地分析。本文强调以发展的、动态演化的思路来研究盆地。现存的一个盆地，可能只是地史期间大盆地的残余（或残留）部分；或是原来彼此分开和独立的几个盆地内的沉积记录组成的沉积物拼盘。一个盆地内现存的次级构造单元可能由年轻的造山运动形成；另一种可能性则是原来的次级单元已被后来的构造-热事件模糊或遮蔽了。在盆地的建造过程中，隆起（包括次级隆起）的时起时伏十分常见；相应地，盆地间的时分时合也十分常见。在泛大陆旋回与大盆地发育间有着内在联系，即：大盆地发育受邻侧的洋盆演化和造山过程制约，故“盆”“山”间的耦合分析是正确认识盆地动态演化的钥匙。体现在构造--古地理重建中，造山带古地理学倡导原地的古地理重建与非原地的古地理重建相结合且以后者为主。非原地的古地理重建可通过定量的（如基于古地磁资料的重建）和定性的两条途径实现。文章讨论了定性重建中的5个要点：1）时间上，要结合“反序”的研究，2）空间上，要结合“反转构造”的研究，3）强调构造复位在古地理重建中的意义，4）盆地建造阶段中的改造事件所起的承前启后作用，和5）盆地动力学与造山动力学的结合研究。 相似文献
17.
James Gunning 《Mathematical Geology》2002,34(1):43-62
Increasing attention has been paid to the use of non-Gaussian distributions as models of heterogeneity in sedimentary formations in recent years. In particular, the Lévy-stable distribution has been shown to be a useful model of the distribution of the increments of data measured in well logs. Frequently, the width of this distribution follows a power–law type scaling with increment lag, thus suggesting a nonstationary, fractal, multivariate Lévy distribution as a useful random field model. However, in this paper we show that it is very difficult to formulate a multivariate Lévy distribution with any nontrivial spatial correlations that can be sampled from rigorously in large models. Conventional sequential simulation techniques require two properties to hold of a multivariate distribution in order to work: (1) the marginal distributions must be of relatively simple form, and (2) in the uncorrelated limit, the multivariate distribution must factor into a product of independent distributions. At least one of these properties will break down in a multivariate Lévy distribution, depending on how it is formulated. This makes a rigorous derivation of a sequential simulation algorithm impossible. Nonetheless, many of the original observations that spurred the original interest in multivariate Lévy distributions can be reproduced with a conventional normal scoring procedure. Secondly, an approximate formulation of a sequential simulation algorithm can adequately reproduce the Lévy distributions of increments and fractal scaling frequently seen in real data. 相似文献
18.
自由对流及其对成岩作用和烃类运移的影响 总被引：2，自引：1，他引：1
自由对流是一种由于流体的密度变化而产生的流体的运动。在沉积盆地,随深度增加,流体的温度也升高,升高的温度可引起流体的热膨胀作用,从而导致地下流体密度随深度而降低,产生垂向密度差。在一定的条件下,该密度差可导致流体产生自由对流。自由对流的流体在运动过程中搬运了大量的矿物质和烃类。由于这些矿物质和烃类的溶解度几乎都与温度有关,因此在对流圈的高温和低温部位,将出现一些矿物质和烃类的溶解、析出或沉淀,从而对成岩作用和烃类运移、聚集构成重要的影响。 相似文献
19.
《Geoforum》2017
Two key figures analyzed in Donna Haraway’s monograph, Primate Visions: Gender Race and Nature in The World of Modern Science (1989) warrant further analysis in the emerging cyber politics of environmental conservation. These figures are Koko, a female lowland gorilla born in the San Francisco Zoo and her companion Dr. Francine (Penny) Patterson, a developmental psychologist who taught Koko how to communicate with a modified form of American Sign Language (ASL). Nine years after Haraway’s initial analysis, Koko and Patterson became early examples of conservation-related Web 2.0 engagement with their unprecedented inter-species America Online chat room encounter with 7811 member participants. Today, Koko has a Twitter account (@kokotweets), a Facebook page, a YouTube channel and a website where users watch videos of Koko celebrating birthdays and donate to ‘distant’ conservation projects. One project site is a gorilla reserve in Cameroon and another is a former pineapple plantation turned private nature preserve in Maui, Hawai’i. Inspired by recent analytical work in animal geographies and feminist political ecology, this article explores complex landscapes of caring, aging and conservation in a time of proliferating social media engagement from colonized sites of enduring privilege. The article argues that new media adds layers of violence, disciplinary techniques and co-dependence to the aging bodies, caring practices and landscapes that Koko, Patterson and others inhabit in California and in the proposed physical spaces of a repurposed pineapple field in Maui. 相似文献
20.
简单斜坡油气富集规律——以松辽盆地西部斜坡北段为例 总被引：16，自引：0，他引：16
斜坡是断陷和凹陷型盆地的重要构造单元，按其断裂发育程度和沉积厚度分为复杂斜坡和简单斜坡。松辽盆地西部斜坡为断裂不发育、平缓的简单斜坡，简单斜坡油气成藏有特殊性，表现在三个方面：一是简单斜坡的原油主要来自临近的凹陷，油气沿砂体以优势路径方式侧向运移，油气呈“线状”分布；二是简单斜坡大规模构造圈闭不发育，圈闭类型以地层、岩性和构造-岩性圈闭为主，其分布受构造带控制，超覆带发育岩性上倾尖灭圈闭，受规模较大的断层控制形成的鼻状构造带上发育断层遮挡和构造-岩性圈闭，不受断层控制的鼻状构造带主要发育构造-岩性圈闭。三是简单斜坡普遍受大气水的淋滤作用，由于游离氧的进入使原油遭受氧化降解作用而稠化，造成简单斜坡稠油分布普遍。这种成藏的特殊性决定了油气富集规律：只有位于油气运移路径上的圈闭才有成藏的可能。简单斜坡油气勘探方向是，在油气运移路径上寻找低幅度构造背景下的岩性油气藏（小规模）、规模较大断层附近寻找断层遮挡油气藏（中等规模）和地层超覆带上寻找岩性上倾尖灭油气藏（大规模）。 相似文献