Stability Criteria of Underground Workings under Zonal Disintegration of Rocks

Using the energy approach as the base, the criteria are developed for brittle rock failure in outcropping in the workings driven in the rock masses of different degree of disturbance. A method is presented for estimating the stability of workings under conditions of zonal disintegration.     

济阳坳陷沙河街组和孔店组烃源岩地球化学特征

对济阳坳陷沙河街组各个层段的有机质丰度、有机质类型和有机质成熟度进行研究。结果表明：沙三段有机碳含量最高,显示出该段烃源岩品质最好,沙四段次之,孔店组有机碳含量最低,其烃源岩品质最差;沙三、沙四段烃源岩以Ⅰ型干酪根为主,含有少量的Ⅱ型干酪根,孔店组以Ⅲ型干酪根为主;在有机质成熟度方面沙三段、沙四段到孔店组成熟度逐渐增高...     

弱渗透松散和坚硬岩石的渗透性测定方法

固体有害废物安全填埋场基础弱渗透岩石的渗透性,大多数情况下都由实验室和野外方法测定．测定方法的适用性取决于岩石种类、岩体状态和渗透性数量级别．在同一实验段内采用不同的实验方法,一情况下导致产生两个数量级的误差,而更大的不可靠性与使用不同的评价方法有关．因为可靠并可引用的渗透性测定值在废物安全填埋场建设中对地质屏障的评价具有重大意义,如果各地能同时列出科研规划,共同研究对所有可能存在的地质屏障岩石进行全面分析评价,确定不同实验方法之间相关关系,以及使评价方法尽可能统一,是十分必要的     

下寒武统优质烃源岩的地球化学特征与形成机制——以鄂西地区天柱山剖面为例

全球范围下寒武统发育的黑色泥岩是一套重要的优质烃源岩。该套烃源岩分布广,但在不同地区厚度和质量差异大,重建其沉积与发育模式对预测优质烃源岩的分布具有重要意义,并可为页岩气勘探提供指导。通过对鄂西地区天柱山剖面下寒武统烃源岩样品开展有机碳、主量元素、微量元素等地球化学分析测试,探讨古气候、古生产力和古海洋环境等对优质烃源岩形成的控制作用,分析下寒武统优质烃源岩的沉积模式、发育机制以及生物活动和海洋环境变化与优质烃源岩形成的耦合关系,结果表明,天柱山剖面下寒武统优质烃源岩段具有高TOC含量（2.63%~8.76%）、高化学蚀变指数（68~76）和高生物来源Ba （平均含量为1 392×10^-6）的特点,且高度富集氧化-还原敏感元素（Mo、U和V）。V/Cr比值、U/Th比值和V/Sc比值指示天柱山剖面下寒武统的水体经历了从硫化缺氧环境到次氧化环境再到氧化环境的变化,与Mo、U富集因子之比指示的氧化-还原环境变化特征相一致。TOC含量与Al、Si、生物来源Ba含量的相关性表明陆源输入对烃源岩有贡献。δ¹³C的变化反映了海平面升降对生物生存环境有影响。研究认为,鄂西地区早寒武世海水的硫化缺氧和表层海洋生产力高是导致有机质大量埋藏、形成优质烃源岩的关键。     

一种基于缆索的堆石混凝土堆石入仓方式及应用

堆石入仓主要解决的是堆石垂直、水平、上下游方向的三维运输问题,基于安徽大龙潭水库拱坝除险加固工程的应用实例,介绍了一种基于缆索的堆石混凝土堆石入仓方式,包括设备构造和堆石流程。经过对比分析该堆石入仓方式与塔吊堆石入仓方式、长臂挖机堆石入仓方式的运行效率和成本,得出结论:基于缆索的堆石入仓方式适用于不具备自卸汽车入仓条件、工期较长、施工速度要求不高的堆石混凝土施工。     

潍北凹陷孔二段有效烃源岩再认识

潍北凹陷烃源岩类型丰富,不同类型烃源岩生烃潜力差别较大,但录井岩性与镜下观察存在较多偏差,有必要对其进行重新识别区分。通过对烃源岩取心样品的微观识别,将潍北凹陷孔二段烃源岩划分为灰质泥岩、油页岩和暗色泥岩三类,结合地化分析明确了不同种类烃源岩的生烃潜力,通过岩心标定测井,对各种烃源岩进行了测井识别区分,通过引入△logR模型对暗色泥岩中的有机碳总量进行计算,对有效烃源岩进行了识别,进而明确了优质烃源岩主要分布在盆地中北部,为选择勘探方向奠定了基础。     

A study of some Egyptian carbonate rocks for the building construction industry

A number of geotechnical analyses were carried out on selected carbonate rock samples from eight sites located in Egypt. This analysis was to assess the suitability of these rocks for building construction aggregate. The analyses included properties of uniaxial compressive strength, tensile strength, porosity, water absorption, and dynamic fragmentation. The success of building construction depends to a large extent on the availability of raw materials at affordable prices. Raw materials commonly used in the building industry include sands, gravels, clays and clay-derived products. Despite the widespread occurrence of carbonate rocks throughout Egypt, the low premium placed on their direct application in the building sector may be explained in two ways: firstly, the lack of awareness of the potential uses of carbonate rocks in the building construction industry (beyond the production of asbestos, ceiling boards, roof sheets and Portland cement); and secondly, the aesthetic application of carbonate rocks in the building construction depends mainly on their physical attributes, a knowledge of which is generally restricted to within the confines of research laboratories and industries. Thus this paper addresses the physical and mechanical characteristics of some Egyptian carbonate rocks, evaluating them for their suitability as building construction aggregates.     

Rare Earths, Trace Element Characteristics of High-Mg Volcanic Rocks of Yixian Formation in Sihetun West Liaoning Province and Its Apocalypse

The high-Mg volcanic rocks of the Yixian Formation in the Sihetun area have the obvious characteristics of mantle-derived lava in rare earth, trace element characteristics with high Mg# (62～70) and high content of compatible elements. In the meantime, the volcanic rocks also have the obvious characteristics of Crust-source material in rare earth, trace element characteristics with high ∑REE (158.78×10-6～359.66×10-6), high (La/Yb)N (14.61～29.60), high La/Nb(2.37～7.52) and high Ba/Nb(67.58～205.96), obvious positive anomaly of Pb and negative anomaly of Nb, Ta in trace element spider-gram. In Sr-Nd-Pb isotope the (87Sr/86Sr)i ratio is higher than 0.706 and the εNd(t) ratio is from -3.4 to -13, both reflect enriched Mantle characteristics. The characteristics above of the volcanic rocks combined with the content of Sr, Ba, Y, Yb and the ratio of Sr/Y show that the volcanic rocks have the property of the Sanukite rocks in Setouchi Japan beside subduction zone, and illuminate that the Sanukite rocks can be formed not only in island-arc near subduction zone but also in intro-plate. The analysis indicates that the high-Mg volcanic rocks in the Sihetun area result from the collective function of mantle-derived lava and crust-source materials. The result illuminates that the West Liaoning region is very special in tectonic geochemical background in Cretaceous in East China, and is an ideal region for us to further study the characteristics of magmatic activity as well as the process of Crust-Mantle interaction in Eastern China.     

根据钻孔资料确定地下岩层产状——通用地质坐标系应用实例(之四)

根据钻孔资料确定地下岩层产状是一个比较复杂的问题。利用赤平极射投影网上的小圆相交方法,可以求得倾斜钻孔资料地下岩层的可能产状,但赤平极射投影网上的小圆作图比较复杂。利用通用地质坐标系可直接在球面投影上计算出两个小圆的交点,能更快更准确地得到结果。