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秦岭造山带沉积岩容矿金矿床地质特征和矿床成因 总被引:5,自引:1,他引:4
讨论了秦岭造山带沉积岩容矿金矿床地质背景、地质特征和矿床成因。认为俯冲碰撞过程中形成的浊积岩系是金矿的主要矿源层,在金矿源层原始沉积时,热水沉积起了重要作用。在褶皱造山过程中,金元素发生了活化、再分配,在层间破碎带、构造片理化带、剪切带等处发生了富集。在印支-燕山期岩浆侵入作用的热驱动下,金矿最终在有利构造部位定位,富集成矿。 相似文献
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在松散地层钻孔,需用高粘度泥浆护壁,但作为水井又需要清水钻进,使含水层畅通无阻。为此,本文介绍一种泥浆循环器,可大大节约洗井时间,缩短工期。 相似文献
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中南部非洲新元古代卢富里安铜-钴矿带是全球最重要的沉积型铜-钴成矿带之一,加丹加超群是该成矿带中主要的沉积地层,其最下部的下罗恩亚群是最主要的赋矿岩性层位。通过对现有资料全面深入的分析对比研究认为,加丹加超群在赞比亚铜带省、西北省与刚国(金)加丹加省之间的发育特征、地层层序构造形式都存在明显差异;赞比亚和刚果(金)加丹加超群下部的罗恩群存在明显的沉积相差异,将其中岩性层位从下到上逐一对比,可能并不能真实反映下罗恩亚群在两个地区之间的差异;刚果(金)下罗恩亚群的沉积成岩时代可能比赞比亚的稍晚。 相似文献
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Variation Characteristics of Ambient NMHCs at Shangdianzi and Lin'an Regional GAW Sites 总被引:2,自引:1,他引:2
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In order to study the variation characteristics of concentration of the atmospheric non-methane hydrocarbons (NMHCs) in background area of China, the atmospheric concentrations of NMHCs were measured at Lin'an (LA) regional GAW (Global Atmosphere Watch) Station (30°25'N, 119°44'E; 132.0 m ASL) and Shangdianzi (SDZ) regional GAW Station (40°19'N, 117°07'E; 286.5 m ASL) with the sorbent sorp-tion/thermal desorption/gas chromatographic method. Totally 145 samples were collected during the period of October 2003 and July 2004. Among the 52 NMHC species of C2-C10 detected there were 26 alkanes, 17 alkenes, and 9 aromatics. The average concentrations of total NMHCs (TNMHCs) at LA and SDZ were (238.5±126.0)×KT9C and (278.7±185.5)x10-9C, respectively. The results showed the ambient concentrations of TNMHCs at LA regional GAW Station increased notably over the last decade. The compositions of NMHCs at SDZ and LA were relatively similar. The proportions of alkanes, alkenes, and aromatics for SDZ and LA were hi ranges of (27.3±4.0)%, (10.3±3.5)%, and (62.5±4.8)%, respectively, with features of vehicle exhaust emissions. The concentrations of NMHCs at the two sites showed obvious diurnal and seasonal variations. The TNMHC concentrations in October-November were high at the two sites, and relatively low in April and July. The diurnal variation patterns at the sites were different. The high TNMHC concentrations at SDZ normally appeared in evening and night, but appeared in morning at LA. The TNMHCs concentrations at the two sites were significantly influenced by the meteorological condition. The high TNMHC concentration associated with the local wind from the urban areas or traffic in upper reaches. 相似文献
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相邻的沉积微相不仅地应力大小不同,地应力方向也存在较大差异。利用有限单元法,通过改变不同的边界条件(包括河道介质和周围岩体的弹性模量、泊松比,河道走向与区域主应力方向夹角及边界应力比),对河道砂体地应力的影响因素进行分析。模拟结果表明,相比于河道周围岩体和区域地应力特征,不同的边界条件对河道砂体地应力大小和方向的改变程度很大,其中河道砂体与周围岩体的弹性模量比、河道走向与区域主应力方向夹角及边界应力比是影响河道砂体现今地应力方向和大小的主要因素。研究结果可以为不同沉积微相下进行人工压裂和井网部署提供参考依据。 相似文献
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中国西部矿产资源开发有关问题的讨论 总被引:2,自引:0,他引:2
资源合理开发利用是西部大开发的重点内容之一.矿产资源的合理开发利用及其后续产业可为地方增加致富就业的机会,将资源优势转化为经济发展的优势,有利于促进地区经济的发展.但西部地区生态环境条件十分脆弱.如何才能发挥西部资源优势,促进地区经济发展,同时又不至对环境造成严重污染,将矿业活动对环境的影响降到最低程度,笔者谈一些不成熟的意见. 相似文献
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辽宁白云金矿床某些基本问题探讨 总被引:8,自引:3,他引:8
白云金矿产于辽宁省东部辽东裂谷增生地体内的辽河群古元古代变质岩系中,矿体主要赋存在呈东西南展布的滑脱构造带,蚀变分带明显,与金矿化密切相关的蚀变作用为钾长石化、绢云母化、碳酸盐化、绿泥石化等,为构造蚀变岩型金矿床。均一法测温结果的主要范围为200 ̄250℃,氢、氧、硫同位素表明成矿溶液以岩浆水为主。矿物流体包裹体、硫同位素等地球化学特征研究表明沸腾作用是矿液沉淀的主要因素。 相似文献