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OB-A型空压机解决了KD-100型钻机在无高压风处无法开钻的难题,并在试验中显示了其优越性. 相似文献
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The three I-type plutons of Guantian(GT),Guidong(GD),Shangbao(SB)and the two S-type plutons of Xucun(XC)and Xiuning(XN) as well as their microgranitoid enclaves in southern China have been studied,Restite in the Motianling(MT) metasomatic granite in this area is described in this paper as well,Microgranitoid enclaves in the I-type granitoids may be divied into autoliths and schlierens which have marked differences both in petrography and geochemistry.In the S-type granitoids,schlierens are the major microgranitoid enclaves,but autoliths are rare.The metasomatic granite contains only restite without other enclaves.The microgranitoid enclaves and their host rocks have close ∈Nd(T)values and the same minerals within them are similar in composition.The microgranitoid enclaves,in general,don‘t represent the products of mixing of the syn-plutonic foreign mafic magma and the host acidic magma.They are the records of the evolution of intermediate-acidic magma itself.The formation of autoliths is related to the interdiffusion of different constituents in magma.Schlierens are the products of immiscible fractionation of the magma. 相似文献
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Two A—type Syenite—Granite Belts in Anhui 总被引:3,自引:0,他引:3
There exist two parallel A-type syenite-granite belts on both banks of the Yangtze River in Anhui Province: one is the Dalongshan-Chengshan-Huangmeijian
belt on the north bank and the other is the Huayuangong-Maotan-Banshiling belt on the south bank. Both of them consist of
syenite, quartz-syenite and alkali feldspar granite, which were formed at about 125 Ma ago and are enriched in alkalies and
high-field-strength elements but depleted in water, with the total alkali accounting for 9–12%. and H2O+ only for 0.50%. The Ga× 10−4/Al ratio is as high as 2.7 to 3.8 for granite. They were formed in the extension stage of ancient rifting. So they are considered
to be the A-type syenite-granite belts. Granites in the two belts resulted from a syenite magma by an AFC mechanism while
the magma was derived from alkali basalt magma through the fractional-crystallization-dominated AFC mechanism.
Financially supported by the National Eighth-Five-Year Science and Technology Breakthrough Project No. 85-901-03-04. 相似文献
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文章通过广西凤凰山银锰矿床中的S-Fe-Cu-Ag-Sn系列矿物黄锡矿,含银黄锡矿,银黄锡矿,硫银锡矿的化学成分标型,标型矿物组合特征的研究,为该矿床的成因,深部隐伏银矿化,矿区及其外围的找矿提供了一定的信息。 相似文献
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安徽煤田地勘公司与中国矿业大学钻探设备研究室合作试制了22.5m、18m、13.5m系列化ZT—A型轻便钻塔。设计最大允许载荷分别为32t、23t、18t。初步使用效果良好。22.5m钻塔在钻场提拉检验中,经受了20t的载荷,并具有重量轻、结构合理、操作安全、加工工艺较简单、易于推广的特点。 相似文献
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分别对川西北哲波山微细浸染型金矿的构造、蚀变、矿化三者进行了详细的阐述,总结出该区构造活动的多发性和继承性制约着矿化的多阶段性的叠加性。矿化、蚀变的广度不能超越构造的限度。构造-蚀变-矿化三者之间的变化存在密切的正相关性。 相似文献
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笔者将南秦岭卡林型-似卡林型金矿床与与其共生的热水沉积成因铅锌矿床,中国滇黔桂卡林型金矿床、卡林型金矿床命名地美国西部卡林金矿床、乌兹别克斯坦穆龙套型金矿床等进行了地质地球化学综合对比研究,可以发现,这些矿床的形成均与现代板块构造活动机制具有密切耦合关系,属于造山期成矿矿床,它们既具有相似特点:容矿建造属沉积岩型,沉积构造环境具有拉张裂陷性质,均显示同生一叠加改造两次成矿作用的特征;它们又具明显差别;所属大地构造背景不同,造山带组成及结构存在明显差别,叠加改造成矿作用表现的复杂和强烈程度差别较大,造山带区域构造演化与大规模成矿作用是同一大陆动力学过程的不同表现。 相似文献