东昆仑地区二道沟石英脉型白钨矿矿床地质特征及找矿前景分析

二道沟钨矿床是目前青海省内发现的规模较大前景较好的石英脉型白钨矿矿床,通过进一步工作,有望成为大型乃至超大型白钨矿床。对二道沟白钨矿成矿地质背景、矿体特征及围岩蚀变进行了分析探讨,结合勘探工作成果初步认为该矿床成因类型为石英脉型白钨矿,并初步分析了二道沟地区该类型矿床的找矿前景,认为该区是寻找与岩体有关的石英脉型钨矿的有利地段。对于区内及邻区白钨矿的找矿工作有一定的参考价值。     

西藏察隅县那阿钨矿矿床地质特征和成矿模式浅析

西藏察隅县那阿钨矿是发育于冈底斯基底岩系中的矽卡岩型白钨矿床。本文从矿区地层、构造、岩浆岩方面分析了矿区的成矿地质背景,总结了矿床地质特征,根据实际勘查工作归纳了矿区的成矿模式,包括三个阶段:第一阶段为区域变质作用形成矿源层阶段,第二阶段是热液交代富集成矿阶段,第三阶段是构造改造阶段。     

浅谈青海省格尔木二道沟白钨矿床地质特征

本文结合青海省格尔木二道沟白钨矿床成矿背景、矿区地质、矿床地质等相关信息综合性的分析了青海省格尔木二道沟白钨矿床地质特征,从而为该地区白钨矿产的分析提供参考。     

黑龙江宝兴沟金矿床地球化学特征及控矿因素

宝兴沟金矿床是位于上黑龙江成矿带上的大型岩金矿床。在充分收集矿区已有资料的基础上,结合矿区钻孔样品及地球化学剖面数据,对矿床地球化学特征进行了研究。研究表明,二十二站组地层成矿元素含量普遍高于克拉克值,且元素变异系数较大,有利于发生迁移,矿体两侧围岩中存在成矿元素向矿体迁移而产生的低值区。地层、构造、岩浆岩是主要的控矿因素,二十二站组地层为矿源层,北东向断裂及其次级断裂控制了矿体的形态和产状,(石英)闪长岩脉、闪长玢岩脉与成矿关系密切,二十二站组地层、北东向构造及岩脉同时存在是寻找金矿体的理想部位。     

甘肃小独山西钨矿床成因探讨

小独山西钨矿床是近年来新发现的大型钨矿床,笔者从地层、构造、岩浆岩、蚀变作用等成矿条件入手,对该矿床的成因进行了探讨。该区地层、构造、岩浆岩条件的完美耦合是该矿床形成的根本原因。矿区下二叠统红柳河组各岩性层中钨元素丰度值高,为该矿床的形成创造了物质条件;矿区极其发育的断裂裂隙系统,为后期成矿热液的运移、物质交换、成矿元素的沉淀富集提供了通道及储存空间;燕山早期的岩浆活动,在为成矿提供热源、物源的同时,使得早期的断裂裂隙系统再次活动,为成矿热液的运移、物质交换、成矿元素的沉淀富集开辟了更为广阔的通道及储存空间;燕山早期岩浆期后热液沿着前期形成的断裂裂隙充填交代,在高温阶段形成石英脉脉型黑钨矿,随着温度的逐渐降低,形成石英脉脉型白钨矿;原生矿床形成后,经过长期的表生作用,进一步次生富集形成沿沟谷产出的钨砂矿。小独山西钨矿床是与酸性岩浆活动有关的充填交代式石英细脉带型(黑)白钨矿矿床。寻找成矿热液运移通道及其方向,将成为今后该区找矿工作的重点。     

甘肃祁青钼矿床石英脉与钼成矿关系探讨

祁青钼矿床的发现是甘肃有色地质勘查局四队近年来在小柳沟钨钼矿区开展地质找矿工作的结果,该矿床矿体的分布、产状以及矿石组构都与矿区石英脉息息相关。祁青钼矿成功勘查对石英脉脉型矿床的勘查评价具有一定的指导意义。本文从矿区石英脉地质特征、产出特征、成矿贡献率、以及石英脉微量元素特征等方面初步讨论了石英脉与钼成矿关系。     

陕西镇安西部棋盘沟钨矿区成矿流体特征研究

镇安西部棋盘沟矿区内的钨矿体主要为石英脉型钨矿，产出于矿区内近SN向断裂中，矿石中金属矿物以白钨矿为主，矿体规模大且品位高，但矿区内未见有岩浆岩体出露，因此明确其成矿流体来源是理解矿床成因的关键。为了探究成矿流体特征，分析了主成矿阶段形成的白钨矿与石英颗粒中主要发育的气液两相包裹体，结果显示包裹体均一温度介于291.4~423.7 ℃之间，热液盐度[w(NaCl)]为5.1%~7.7%，流体的密度范围为0.52~1.08 g/cm³。这表明矿区成矿流体属于中高温、低盐度流体，与典型热液钨矿流体相似，H、O同位素测定结果显示其主要来源为岩浆水，S同位素落入岩浆岩S同位素组成范围内，反映矿区钨矿来源于岩浆热液。与周边矿区似层状钨矿流体包裹体相比，棋盘沟矿区成矿流体均一温度明显较高，说明近SN向构造是成矿热液运移的主要通道，在成矿流体运移过程中，顺着该区NNE向断裂裂隙上升，形成石英脉型白钨矿。随着成矿热液温度持续降低，矿液沿层间裂隙灌入形成似层状型白钨矿。     

湘中双峰包金山Au-Sb-W矿床钨成矿特征

包金山Au-Sb-W矿床位于湘中成矿区的东北部。该矿床中W以白钨矿的形式产出,产于石英脉中。白钨矿的形成分为两个阶段。第一阶段白钨矿产于乳白色石英脉脉壁两侧,呈对称带状;第二阶段白钨矿以团块状产于烟灰色石英脉中及脉壁。两期白钨矿的晶体化学式分别为Ca_(0.890)[W_(1.035)O_4]和Ca_(0.886)[W_(1.037)O_4]。微量元素种类相似,以类质同象的形式存在。通过分析认为,岩体和地层共同为矿床白钨矿提供了成矿物质来源,最终与围岩中Ca结合沉淀,形成白钨矿。在这一过程中,断裂构造连同地层一起起到了控制作用,岩浆活动为成矿提供了能量。     

江西省安福县浒西钨矿地质特征及找矿标志

浒西钨矿是岩浆期后中-高温热液充填石英脉型钨矿床,以第一手详实的地质资料为基础,试图从浒西钨矿成矿地质背景、矿区地层、构造、岩浆岩等成矿控矿要素、矿体地质特征入手,总结浒西钨矿床地质特征,并就钨矿床的矿床成因、找矿标志进行探讨。     

瑶岗仙钨矿床两类白钨矿地质特征对比研究

瑶岗仙矿床是南岭地区典型的石英脉型黑钨矿床,并伴生石英脉型和矽卡岩型两类白钨矿化。经过野外地质现象系统的观察以及精细的镜下矿物学研究,厘定了两种类型白钨矿化的成矿阶段,对不同类型白钨矿进行了宏观和微观地质特征对比。结果表明,石英脉型和矽卡岩型白钨矿的成矿环境、成矿规模、显微组构等有着明显区别。通过对比两种矿体白钨矿的岩相学特征,约束不同类型白钨矿的成矿过程与成矿作用。     

论从实践理解世界的物质性和自然世界的先在性

马克思主义唯物论是一种物本主义形态的唯物论,还是一种超越物本主义形态、从实践理解世界的本质相关问题的实践的唯物主义的唯物论?这是一个我们必须搞清楚的有关马克思主义唯物论的本质规定性和精神实质的重大问题.在考察物本主义的唯物论及其思维方式的局限性的基础上,揭示了马克思主义唯物论是现代的、实践的唯物主义,并重点研讨了马克思主义唯物论关于从实践理解世界的物质性和自然世界的先在性的原理,以期为马克思主义唯物论进一步阐明人类世界的实践性原理奠定基础.     

Effect of cyproheptadine on the ultrastructure of the neurons of the arcuate nucleus in the hypothalamus of the rat

The data are presented on changes in the rat arcuate nuclear neuron ultrastructure after using cyproheptadine (peritol, Egyt Pharmaceutical Works, Hungary) in a water suspension at a dose of 20 mg/kg once daily during 7 successive days and twice a day within 10 days. It was shown that cyproheptadine decreases the functional activity of the arcuate nuclear neurons, depending on the total amount of the drug used. Cyproheptadine-induced inhibition of the forming neurohormone release from neurons is likely to be one of the mechanisms of its therapeutic effect in Itsenko-Cushing's disease.     

Characteristics of the sympathetic innervation of the nictitating membrane and of the vasculature of the nose and tongue of the cat

Vasomotor responses from the nasal mucosa and tongue, and contractions of the nictitating membrane, were recorded on stimulation of the cervical sympathetic or internal carotid nerves. Preganglionic sympathetic nerve fibres which elicited a membrane response possessed a lower threshold than those which evoked nasal vasoconstriction, while the latter displayed a lower threshold than fibres which evoked tongue vasoconstriction. The sympathetic vasodilator fibres to the tongue whose activity was revealed after alpha-receptor blockade, had a similar threshold to the vasoconstrictor fibres. Membrane contraction, nasal vasoconstriction and occasionally tongue vasoconstriction could be evoked by stimulating the internal carotid nerve. The postganglionic fibres innervating the nasal mucosa had a similar threshold to those of the nictitating membrane, which may indicate that there are small myelinated fibres innervating the mucosa. The preganglionic compound nerve action potential had four major components, S1-S4. S1, S2 and usually S3 fibres were associated with membrane contraction; S2, S3 and sometimes S1 fibres were associated with nasal vasoconstriction; and S3, usually S2 and occasionally S1 fibres were associated with vasoconstriction in the tongue. It is concluded that each of these three groups of nerve fibres, but not S4 fibres, may include fibres associated functionally with the three effectors. There was a considerable difference between the relative amplitude of the responses of the three effectors elicited by stimulation of the cervical sympathetic nerve at frequencies between 0.2 and 2 Hz. Vasoconstrictor responses were relatively larger than membrane contractions suggesting differences in the mechanisms of neurotransmission at the neuroeffector junctions.     

Structure of the attachment of the vocal ligament to the perichondrium of the thyroid cartilage

The ventral attachement of the ligamentum vocale of eleven larynges (new-born and adults has been studied in sagittal, frontal and horizontal sections. 1. Supplementary to the known structure of the ventral attachement of the ligamentum vocale we have noticed collagen fibers which ascend in the inner angle of the thyroid cartilage and which partly cross to the other side. Sometimes a few fibers which are running downward have been observed. This structure of the attachement must be more firm than the known structure. 2. Moreover it has been observed that a lot of the angles of the crossing collagen fibers in the cartilage of the lamina mediana (near the attachement of the ligamentum vocale) are right-angled, whereas the angles of the fibers which lie in the laminae laterales in their majority are acute-angled. This phenomenon also is interpreted as a structure which makes the lamina mediana firmer. The fact, that this structure is not so evident in the specimens of the new-born as in those of the adults indicates that there are postnatal changes in the structure of the lamina mediana.