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在社会主义市场经济条件下 ,企业流动资金的管理、运用 ,是整个企业生产经营的关键 ,是提高企业经济效益 ,增加职工收入 ,加速资金周转的龙头。为此 ,企业必须实行以资金管理为中心 ,树立资金管理的新观念 ,拓宽资金渠道 ,压缩资金占用 ,加强监督检查 ,完善考核办法 ,实行集约管理。通过采取这些措施 ,才能提高资金的使用效果 ,促进资金的良性循环。企业流动资金的多少与运用的好坏 ,直接反映企业的经营和竞争能力 ,是一个企业生产经营好坏的关键 ,是企业能否正常运转 ,能否提高效益的基础。如果企业的流动资金充足 ,则企业就能购买其生产经… 相似文献
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中国勘察设计杂志社全体员工 《中国勘察设计》2004,(11):63-63
尊敬的领导,广大的读者: 大家好!《中国勘察设计》杂志在改革开放的康庄大道上风雨兼程的走过了二十个年头了,2005年5月,我们将迎来她20岁的华诞!二十年来,在建设部和中国勘察设计协会的领导下,她坚守既定的办刊宗旨,始终立足于勘察设计行业,宣传改革开放的大好形势,坚持政策导向,发布专业资讯,传播新观念,介绍新经验,开阔新视野,她现已成为行业的“窗口”,学者的论坛,设计师的良师益友,广大读者的知心朋友。二十年来,她紧紧围绕中国勘察设计咨询行业的改企建制、企业发展、经营管理、学术交流等一系列热点和焦点问题,大力反映行业的新进… 相似文献
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如果把大洋钻探比作人生,那么50岁的国际大洋钻探,历经沧桑,砥砺前行,波澜壮阔,功成名就,但也正面临重整旗鼓,再次出发;而20岁的中国大洋钻探,风华正茂,后来居上,年富力强,踌躅满志,但在新世纪地球系统科学的号角声中,能否站在巨人的肩膀上,整装出发,打造全球视野,引领地球科学的前沿? 相似文献
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一、五台系,变质岩内铁矿,因变质甚深,与其围岩俱变片岩状,原来产状及成因住往不易追求,变质岩系地层既然很厚,代表的地质时代也很长,铁矿的种类似很多,无论是水成的,火成的,热液等成的矿,恐都有代表,现时非有很精确和深刻的研究,恐不能分辨清楚。根据现时的了解,有两个不同的铁矿产状,即: 相似文献
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赵国连 《沉积与特提斯地质》2000,20(3):97-104
本文介绍了层序地层的发展历史,总结了各阶段的主要理论和概念,以及各阶段所取得的成就,指出各阶段的理论发及存在的不足,由此而追索到现代序地层学的基本概念及理论的由来,总的来说,层序地层不它历了初期阶段,地震地层学阶段和现代层序地层学三个发展阶段,其中主要涉及层序控制的因素,海平面变化,可容纳空间变化和体系域类型等概念,笔者认为层序地层不发展主要原因是地震勘技术的发展及石油工业的发展,作为边缘学科,它与诸多的学科都有较深的渊源,笔者认为,正是在这些结合点上,层序地层学才得到了极大的应用,笔者认为陆相层离地层学在中国有了较大的发展,在国际上属邻先地位,本文总结了层序地层学的发展历史,现状及可能的发展方向,这将有利人们进一步了解本学科的进展。 相似文献
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青藏高原如此令人神往,在于它的超然与变幻、壮美与奔放、神圣与惊异,然而又静谧无息。踏上这片神奇的土地,问苍天,叩大地,谁主沉浮,终归难言尽。百年探秘,世代穷追逐,代代不了情。有人说:这里距天际最近,可上天揽月,倾听天籁之声;亦有人云:登高远望,一览众山小,却又高处不胜寒。应当说,高原地质人的感悟是最深刻的,只缘他们踏遍了这里的山山水水、沟沟坎坎,战山险,斗风寒,抗缺氧,突破绝地无人区,用生命和热血谱写了一首首可歌可泣的壮丽诗篇,用勤奋和睿智的笔描绘出万物变迁的印记,从容揭开神秘的面纱,用手中的镜头和悠然迸发的灵感捕捉下… 相似文献
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宽甸群中的层控矿床 总被引：1，自引：0，他引：1
The stratabound mineral deposits in the Kuandian Group (PtK) are all transformed deposits and might be classified into two types: syngenetic transformed deposits, such as boron, iron, rare-earth, pyrite and apatite ores, and metamorphic hydrothermal transformed deposits, such as magnesite, asbestos and talc. The boron deposits in the Kuandian Group are confined to the middle part of the Kuandian geosyncline 45 km in width and 400 km in length, constituting a boron ore zone trending in the same direction as the geosyncline itself. They may be classified commerrcially into two types, i. e., "white boron ore" and "black boron ore". The former, made up mainly of boronmagnesite and suanite, are rarely associated with ferruginous minerals, while the latter contains ludwigite and magnetite, forming ore of mixed type, the former occurs unexceptionally in PtK: while the latter can be found in three stratigraphic positions, i. e., PtK22, PtK41 and PtK62. The B-Fe-TR formation has formed in time and space a metallogenic sequence and three obliquely arranged zones on account of the uneven distribution of useful element composition in the original strata. Within the Kuandian geosyncline, therefore, three subformations could be recognized from its periphery in inward succession: Fe-TR, B-Fe-TR and B-(Fe) subformations, accompanied by an increase in B and a decrease in Fe. So far as economic significance is concerned, the iron deposits in the Kuandian Group are likely to be assigned to four types, namely, Fe-TR type (Shengtieling type), Fe-B type (Wengquangou type), Fe-rich and sulfide-bearing type (Yanglin type) and Fe-magnesite-magnetite type (Daankou type). The "sedimentation- transformed" idea ought to be emphasized in the whole process of mineral exploration for stratabound deposits in Kuandian Group except for metamorphic-hydrothermal-transformed ones. Sedimentationis the base of being transformed, which has been verified by years of survey and prospecting. 相似文献
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Comparison of the Typical Metallogenic Systems in the North Slope of the Tongbai‐East Qinling Mountains and its Geologic Implications 总被引：4，自引：0，他引：4
The Tongbai-East Qinling Mountains, an important part of the Central orogenic belt, is one of the most important metallogenic belts in China and contains lots of orogenic-type and VMS-type (Volcanogenic Massive Sulfide type) metallogenic systems. The Dahe and Shuidongling VMS-type Cu-Zn deposits, located in the Erlangping Group in Tongbai and East Qinling Mountains, respectively, show similar geological and geochemical features. The Huoshenmiao Formation in the East Qinling region and the Liushanyan Formation in the Tongbai region are spilite-keratophyre sequences occurring in the western and eastern sides of the Nanyang Basin, respectively, and are interpreted to be equivalent to each other. The orogenic-type Au-Ag deposits can be subdivided into two styles; namely, fault- or structure-controlled (e.g. Yindonggou) and stratabound (e.g. Poshan). The Poshan and Yindongpo orogenic-type Au-Ag deposits, whose ore bodies are strictly hosted in carbonaceous strata in the Tongbai Mountains, show obvious stratabound characteristics. Their ore-fluids are enriched in K+ and SO42? and are regarded as K+-SO42? types. The Pb-isotope ratios of sulfides of the ores are extremely uniform and significantly different from those of the tectonostratigraphic terranes of the Qinling orogens except for the ore-hosting strata of the Waitoushan Formation. The Yindonggou and Xuyaogou orogenic Au-Ag deposits in the East Qinling Mountains, whose ore bodies are hosted in the faults cutting the hosting strata or granite body, show fault-controlled characteristics. Their ore-fluids belong to the Na+-Cl? type. The Pb-isotope ratios of sulfides of ores are similar to those of the northern Qinling orogenic belt. The Waitoushan Formation, dominated by carbonaceous sericite-rich schists and only occurring in Tongbai region, should be detached from the Erlangping Group, which occurs both in the western and eastern sides of the Nanyang Basin. Future ore exploration in the Tongbai-East Qinling Mountains should focus on fault-controlled Au-Ag lodes. 相似文献
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桐柏山区的围山城金银成矿带包括破山特大型银矿、银洞坡大型金矿、银洞岭大型银多金属矿床及一些矿点,所有矿床赋存于上元古界歪头山组地层,并具有层控特征。矿石矿物的铅同位素组成为206Pb/204Pb=16.753~17.216,207Pb/204Pb=15.417~15.638,208Pb/204Pb=38.251~39.050;与歪头山组地层的铅同位素组成一致,而与桐柏地区的其他地层、岩体差别较大,表明成矿物质来自赋矿地层歪头山组。围山城成矿带应属于典型的层控造山型金银成矿系统,它形成于中生代扬子与华北板块的陆陆碰撞造山过程,碰撞造山期间的下插板片变质脱水诱发了矿带内流体成矿系统的发育,强烈的流体-岩石相互作用使歪头山组内的成矿物质被萃取、迁移、聚集到碳质绢云片岩层。 相似文献
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In the eastern Sierras Pampeanas, Central Argentina, tourmalinites and coticules are found in close association with stratabound scheelite deposits in metamorphic terranes. In Sierra Grande (Agua de Ramón and Ambul districts) and Sierra de Altautina, tourmalinites are associated with stratabound scheelite deposits related to orthoamphibolites. In the Pampa del Tamboreo area, tourmalinites are located in biotite schists stratigraphically related to acid to intermediate metavolcanic rocks and scheelite-bearing quartzites.The mineral chemistry and boron isotopic compositions of tourmalinite-hosted and vein-hosted tourmalines are investigated. Overall, the tourmalines belong to the dravite-schorl series and are generally aluminous; Fe/(Fe+Mg) ranges from 0.33 to 0.85, Al/(Al+Fe+Mg) from 0.66 to 0.76 and the amount of X-site vacancy (0.12–0.48) indicates significant foitite components. Their boron isotopic compositions (δ11B) are from −24.0‰ to−15.0‰.Similar mineral chemistries and boron isotopic values for tourmaline in tourmalinites related to stratabound scheelite mineralisation and in tungsten-bearing quartz veins suggest a common source for the boron and probably the tungsten. The field, chemical and isotopic relationships are consistent with tungsten and boron in quartz-vein deposits being remobilised from stratabound scheelite and tourmalinite, dominantly by liquid-state transfer associated with regional shear zones. Tungsten and boron in the original sedimentary sequence (now meta-exhalites) are ascribed to volcanogenic exhalations. 相似文献
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南秦岭柞山地区铜矿成矿类型、成矿规律及找矿预测 总被引：2，自引：0，他引：2
[摘 要]南秦岭柞山地区位于陕西省东南部,其西起柞水县,东到山阳县,面积约3000km2。其地处南秦岭海西-印支褶皱带东段,主体夹持于商丹缝合带与凤镇-山阳大断裂之间。作者总结了区域成矿地质背景,对热卤水喷流沉积型铜(银铅)矿、沉积-改造层控型铜矿、热液脉型铜(镍)矿、矽卡岩型铜(铁)矿、震裂岩型铜矿、斑岩型铜(钼、金)矿等6 种铜矿成矿类型的特征进行了探讨,在此基础上阐述了柞山地区铜矿的成矿规律,指出热水喷流型铜矿、斑岩型铜矿、沉积-改造层控型铜矿最具找矿潜力。目前已知的矿床(点)均受具导浆、导热、导流、导矿功能的区域性凤镇-山阳大断裂控制,并沿其两侧展布。未来一段时期,柞山地区铜矿找矿主攻类型为热水喷流型铜矿、斑岩型铜矿、沉积-改造层控型铜矿。找矿靶区首推柞水县银洞子矿床深部、山阳县池沟铜矿点、柞水县冷水沟铜矿点,次为柞水县张家坪铜矿点、山阳县色河铺铜矿点。通过进一步勘查有望取得铜矿找矿的重大突破。 相似文献
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Ying Wang Shu Zhang Zhiguo Cheng He Huang Jinchao Ye 《International Geology Review》2017,59(16):2065-2077
The strata-bound Pb–Zn deposits in western China share many similarities and are controversial in genesis. The large Uragen Pb–Zn deposit is located in the northwestern part of the Kashgar sag, southwest of Tarim Basin, Xinjiang, NW China. With the 980.9 Mt tons of Pb–Zn ores at 0.45%Pb and 2.61%Zn, it is the third largest known Pb–Zn deposits in China. The orebodies are stratiform and stratabound and are predominantly controlled by the Uragen syncline that has an E–W axial trend. Mineralization mostly occurs in sandstones and conglomerates of the Lower Cretaceous Kezilesu Group (K1kz), with a small amount in the Palaeocene limestone. The main ore types consist predominantly of disseminated ore with minor massive ore, veined ore, and breccia ore. The primary metal minerals are composed of sphalerite, galena, pyrite, and minor arsenopyrite and chalcopyrite, and the supergene metal minerals include smithsonite, cegamite, beudantite, jarosite, limonite, and minor hemimorphite. The gangue minerals are composed of dolomite, calcite, quartz, celestite, and gypsium. Our new Rb–Sr isotopic analyses on the separated sphalerite, galena yielded an isochron age of 55.1 ± 1.6 Ma, coeval to an isochron age of 55.4 ± 2.2 Ma by Sm–Nd isotopic data. This age is much younger than the youngest ore-bearing strata (E11, 65.5–61.7 Ma), arguing for an epigenetic origin. The calculated initial 87Sr/86Sr ratio of sulphides is 0.710322, which is much lower than those of basement formation, regional bituminous sandstone, and even the ore-bearing strata, but higher than the regional mantle-derived, alkaline volcanic rocks and marine carbonate. The calculated initial 143Nd/144Nd ratio of calcite and galena is 0.512081. These data suggest that the metals may be chiefly derived from crust, possibly from the minor contribution of mantle materials. Our new-age data, in combination with the previous data, suggest that there probably is a huge medium-low-temperature epigenetic stratabound Pb–Zn belt, which is possibly correlated to the India–Asia collision event. 相似文献
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辽宁省凤城市四道门沟铁矿床地质特征及成因分析 总被引：1，自引：0，他引：1
辽宁省凤城市四道门沟铁矿床位于辽东铁、硼成矿带内。以下元古界辽河群变质岩系最为发育,褶皱构造是直接控制本区变质层控铁硼矿的重要控矿条件,其控制着矿体的产出空间位置,并控制着区内铁矿体的展布特征。该区的铁矿属于火山沉积变质-超变质热液迭生层控矿床,矿石自然类型为磁铁矿-透闪石型,局部有磁铁矿-蛇纹石型和磁铁矿-硼镁铁矿型。 相似文献