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四川是一个石材大省。本文依据详尽的经济地质资料介绍了四川主要高档优质石材。四川产出的优质石材,包括红色系列、黑色系列、蓝绿色系列的花岗石;白色系列、黑色系列的高档大理石,在国内外拥有广大的潜在市场。鉴于此,提出了关于四川石材开发利用的有益建议。 相似文献
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扬子地块东南缘板岩带中剪切带金矿床主要有三种成因类型,即糜棱岩型、石英脉型及蚀变岩型,剪切带对其形成具有明显控制作用.矿体主要受控于如下构造:1-4级多级构造,是由韧性剪切带和脆-韧性剪切带或脆性断层所组成,构造形态变化地段,包括弧形剪切带顶部扩容区及剪切带交汇部位;构造强应变及其叠加部位,这些地段系由超糜棱岩、糜棱岩、碎裂岩所组成;构造多期变形地段。本文还建立了板岩带剪切带型金矿床的动力成矿模式;划分了金矿形成四个阶段,即背景岩石形成;成矿物质运移;主期动力成矿及矿床改造、再造阶段。 相似文献
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结合在建的广昆铁路炭质板岩地区隧道施工,着重介绍了炭质板岩隧道施工中开挖、支护及施工安全的技术措施、工程效果与体会。 相似文献
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Y. L. Zhang Z. F. Wang K. L. Luo M. J. Ding W. Zhang X. D. Lin X. C. Yang 《Environmental Geology》2007,52(4):679-684
The environment of Mt. Qomolangma (Everest) area is of great significance to the global environmental background and environmental
change research. However, there are few studies on the content and distribution of soil trace elements in the area. About
130 soil samples were collected nearby the Rongbuk valley at the northern slope of the Qomolangma from 4,400 to 6,600 m elevations.
Nine soil trace elements, Cr, Zn, Sr, Pb, Ni, Co, Cd, Mn, Cu, were analyzed with ICP-AES (inductively coupled plasma atom
emission spectrometry). The results showed that soil trace elements content increased with altitude; the content of the Cd
in this area was very high, which was 5.8 times of the average content of Chinese soil. There was a noticeable change point
for soil trace elements content at the altitude of 5,800 m, and the content of Cd increased abruptly above 5,800 m. This point
was just located at the boundary of two types of rocks. The Late Precambrian-Neoproterozoic granite–gneiss and metacryst migmatized
interbedded with marble located below 5,800 m; black-dark slate and marl of Cambrian located above 5,800 m (including 5,800 m),
the geochemical characteristic of different rocks was the main factors controlling the soil trace elements content in the
northern slope of Qomolangma Mountain. 相似文献
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以在建成兰铁路松潘隧道为工程实例,探讨研究地下水和构造应力共同作用下炭质板岩隧道变形特征。通过变形原因分析,采取设置长锚杆、注浆加固松散围岩、加强钢拱架锁脚等措施,能够有效控制变形。将软岩变形控制措施纳入动态设计是一种较为经济合理的手段。通过工程试验,动态调整工程措施,优化变形控制方案,对成兰铁路隧道建设具有较好的指导意义和工程借鉴。 相似文献