四川省岩盐矿产资源研究

根据多年从事四川岩盐矿产勘查开发和科研成果积累的资料，对四川岩盐矿产的时空分布、成矿特征、矿床类型、资源藏量及资源优势等诸多方面作一概要的综述，旨在促进四川岩盐矿产勘查开发，推动井矿盐及盐化工业的发展。     

深部岩盐取心钻探技术

利用水井钻机钻探,开展岩盐深孔取心,采用合理钻孔结构和优化钻具组合,并配以适宜的饱和盐水钻井液和取心钻探工艺,成功地实施了连续岩盐取心,收到了良好的效果。结合濮阳岩盐普查项目,介绍了深部岩盐取心钻探技术。     

利用测井信息评价盐湖相烃源岩

盐湖相烃源岩富含膏、盐质成分,使其测井响应特征发生极大改变,给测井评价烃源岩带来困难。基于实测数据,分析了盐湖相烃源岩中普遍发育的纯泥岩、含膏(盐)泥岩和膏(盐)质泥岩有机碳含量的测井响应模式,发现纯泥岩和含膏(盐)泥岩TOC与AC和LogRt呈正比,与DEN呈反比,膏(盐)质泥岩TOC与DEN呈正比,与LogRt呈反比,并基于此建立了盐湖相烃源岩测井评价方法,即首先利用ΔGR区分岩性,再针对不同岩性建立TOC评价模型,最后根据实测S₁+S₂和TOC建立相关关系,就可以求取烃源岩的TOC和S₁+S₂。利用该方法对东营凹陷沙四下亚段烃源岩性质和展布进行分析,发现预测TOC与实测TOC吻合程度高,具有一定推广价值。     

江苏盐田深井绳索取心钻探技术

江苏省地矿局近几年来在金坛，淮安两大盐田开展钻探工作，用绳索取心钻进４９４７ｍ，平均孔深１２３７ｍ采了相应的技术措施，取得了显著效果钻探台月效率达７２４ｍ岩心采取率达９０％以上，钻头寿命７６７ｍ／个；绳索取心成功率达９７．８％，使效率，质量增高，成本，事故率明显下降。     

Memory Effects in Rock Salt Under Triaxial Stress State and Their Use for Stress Measurement in a Rock Mass

Summary Regularities of memory effects in rock salt specimens under triaxial stress state were investigated. Each specimen was subjected to two loading cycles. The first cycle was axisymmetric triaxial compression (σ₁ >σ₂=σ₃). The second cycle was uniaxial compression in the direction of σ₁ of the first cycle. Distinct acoustic emission (AE) and deformation memory effects were observed in the second cycle at the stress value equal to a linear combination of the first cycle principal stresses given by σ₁− (k + 1) σ₃, where k is about 0.5–0.6 for rock salt. Anomalies in deformation curves were found to be more reliable than the AE methods in distinguishing memory symptoms. The necessary pre-requisite for memory formation in the first cycle was that σ₁ exceeded the elastic limit, corresponding to the given confining stress σ₃. Inflections in uniaxial stress versus axial strain and lateral strain curves, in the second cycle, were observed at equal stress values if in the first cycle σ₁ exceeded the elastic limit and memory-forming damage was induced. If there was no memory-forming damage, those inflections were seen at different stress values. This characteristic was used to distinguish between true memory effects and natural characteristic points in deformation curves derived from rock salt testing. A new memory symptom was established, namely a turn point in curve “uniaxial stress versus differential coefficient of lateral strains”. The results form a basis for application of the memory effects for stress measurement in rock salt masses.     

一种有效的岩盐流体包裹体薄片的制作方法

制备高质量的岩盐流体包裹体薄片是进行岩盐中相关流体地球化学研究的关键与前提。但在现有的制片方法中,采用饱和氯化钾溶液和导热较快的油作为研磨液与抛光液的制片方法会在一定程度上污染岩盐样品。同时,利用小刀直接沿岩盐解理切割而获取解理片的方法,会因解理片的面积较小或其局部发生破碎而不利于镜下岩盐中流体包裹体岩相学特征的完整观察。基于此,本论文建立了一种以无水乙醇为流体介质的岩盐流体包裹体薄片的制作方法,即无水乙醇作为流体介质贯穿于整个制片过程,包括切割刀片的冷却液、研磨液、抛光粉润湿剂(抛光液)以及对岩盐样品进行超声波清洗的清洗液,皆以无水乙醇为流体介质。利用该方法制备的岩盐流体包裹体薄片可以有效地克服现有制片方法的缺陷,避免岩盐的溶解、变形和荧光的干扰等后期污染,从而达到保留和完整代表岩盐样品中原始地质信息的目的。     

盐岩地下储气库体积收敛失效概率分析与模型试验验证

盐岩地下储气库受盐岩蠕变特性影响会产生较大的体积收缩变形,影响储气库安全稳定运行。目前对地下储气库体积稳定性分析方法和评价准则各国没有统一标准,国内主要采用数值计算的方法来评价储气库体积稳定性。以江苏金坛盐矿地下储气库体积收敛数值分析为基础,借鉴国外盐岩地下储气库稳定性评价标准,建立盐岩地下储气库体积收敛失效风险评价矩阵,采用一次二阶矩法显示功能函数分析储气库体积收敛失效概率,分析得出：储气库在长期恒定内压工况下体积收敛失效概率随内压的增大而减小;在短期调峰低压工况下体积收敛失效概率随内压的减小而增大;最小内压应保持在4.2 MPa以上。通过交变气压条件下层状盐岩地下储气库大型三维地质力学模型试验得出:储气库体积收敛变形随内压的增大而减小;短期运行最小内压应大于4.0 MPa。模型试验结果与失效概率分析结论较为相似。因此,为避免盐岩地下储气库产生体积收敛破坏,应保证调峰短期最小内压在4.0 MPa以上。     

熔融制样X射线荧光光谱法测定岩盐中的主量成分

以XRF分析岩盐,需解决标准物质缺乏和Cl在分析过程中的损失问题,选择合适的前处理方法以保证结果重现性。经实验发现用于粉末压片法的人工标准物质中氯化钠、硫酸钙等组分经X射线照射后呈现向样片表面扩散的趋势,其中氯化钠进一步分解,难以建立稳定的工作曲线;熔融制样则不存在这一问题,具备定量基础。本文选择熔融制样作为前处理方法,将光谱纯盐类、氧化物与土壤、水系沉积物国家标准物质以不同比例混合,配制人工标准物质建立工作曲线。熔融制样条件为:取样量0.6000 g,四硼酸锂+偏硼酸锂(12:22)混合熔剂10.000 g,熔融温度1000℃,预熔时间300 s,熔样时间300 s,静置时间30 s,所得样片平整通透,因样品中所含Cl具有脱模效果无需补充脱模剂。本方法测定主量元素的精密度(RSD)均小于1.5%,与经典方法相比减少了分析时间与试剂消耗,可作为岩盐主量成分分析的备选方法。     

云阳黄岭岩盐矿ZK0001深孔取心技术

云阳黄岭矿区ZK0001岩盐探矿井完钻井深3805 m,是重庆市地勘局取心垂深最深的一口盐矿井。在钻探取心过程中,选用新川6-5型单动双管取心筒,PDC取心钻头、表镶金刚石取心钻头并严格按照取心规程操作,克服了地层破碎、井径缩径、岩心堵塞、盐析结晶等诸多问题,在3159.85～3805 m井段进行取心,取心进尺254.49 m,单筒平均进尺13.39 m,平均收获率98.1%,获取盐岩层厚53.11 m,取心质量优异,为该区域构造深部盐矿勘探和开采积累了宝贵的经验。     

充分发挥资源优势,大力开发岩盐矿产

我国目前的盐业生产主要以海盐为主，由于海盐生产受气候和土地条件的严重制约，因此，多年来我国的盐业生产一直处于一种不稳定的状态中，纵观世界盐业近几十年来的发展方向，海盐在大幅度减少，而岩盐生产却和到了大幅度的发展，并逐渐取代了海盐。与海盐相比，岩盐具有很多优势，因此，在综合分析世界盐业发展的基础上提出，我国应大力发展岩盐生产，最终实现以岩盐取代海盐的战略目标。     

陕北奥陶纪米脂—绥德岩盐田米脂姬家峁矿区O_2m_5~6亚段岩盐资源及开采条件评价

在充分分析米脂—绥德岩盐田地质特征的基础上,对位于其中部的米脂姬家峁矿区O2m65亚段盐矿层赋存特征进行了研究,预测了矿区O2m65亚段岩盐资源储量,并对其开采条件进行了评价。     

Experimental Study of Temperature Effects on Physical and Mechanical Characteristics of Salt Rock

Summary. Because of its advantageous physical and mechanical characteristics, salt rock is considered an excellent host rock for nuclear waste disposal. Nuclear wastes in a salt rock repository will continue to emit radiation and thermal energy for decades after placement, resulting in a significant rise of the surrounding salt rock temperature. Consequently, study of the physical and mechanical characteristics of salt rock under different temperature conditions is essential to ensure the integrity of the salt rock repository and the safe isolation of nuclear wastes from the biosphere. Through a series of physical and mechanical tests on thenardite salt rock at different temperatures (ranging from 20 °C to 240 °C), it is found that the mechanical parameters have different reactions to a changing temperature. Tests show that the ultrasonic velocity of samples decreases with temperature increase and both the uniaxial compressive strength and axial strain increase with temperature, whereas the tangent modulus E_t goes in an opposite direction. Meanwhile, the plastic strain increases gradually and strain-softening behavior of the samples becomes increasingly evident. In the pre-set angle shear tests, both the cohesion and internal friction angle increase with temperature. Results obtained in direct shear illustrate that both the peak shear strength and the ultimate shear strength increase with temperature. We conclude that the behavior of thenardite salt rock at high temperatures is still advantageous to the integrity of salt rock repository, assuring the safe isolation of nuclear wastes from the biosphere.     

Discrete Element Modeling of Rock Fragmentation upon Impact in Rock Fall Analysis

A discrete element code has been used to simulate impact-induced rock fragmentation in rock fall analysis using a simplified impact model inspired by the theory of vibrations for foundations on elastic media. The impact velocity, the angle of incidence, pre-existing fractures, and the ground stiffness all play important roles in impact fragmentation. Based on the simulation results, impact fragmentation occurs locally at the impact zone without generating large fragments for a homogeneous rock block. Large fragments are generated only when there are open pre-existing fractures in the rock block or when there are fully persistent closed fractures. Softer ground tends to reduce the potential for impact fragmentation. Energy transformation and failure occur only during impact including approach and restitution stages. Friction energy loss accounts for most of the energy loss during the fragmentation process, while tensile cracking energy loss is not significant.     

裂隙化岩体中圆形断面调压井围岩稳定性分析

块体理论是适用于裂隙化岩体变形失稳分析的有效方法。运用块体理论赤平投影法研究某水电站超大型调压井围岩随机块体的稳定性,将圆形断面调压井开挖临空面抽象简化为八个方位的边墙加以研究,分析了井周各部位可能的关键块体及其运动形式,计算了关键块体的净滑力。分析结果对工程施工具有可靠的现实指导作用,为锚固设计和永久衬砌设计提供了依据,可供类似工程参考。     

Analysis of Inflatable Rock Bolts

An inflatable bolt is integrated in the rock mass through the friction and mechanical interlock at the bolt–rock interface. The pullout resistance of the inflatable bolt is determined by the contact stress at the interface. The contact stress is composed of two parts, termed the primary and secondary contact stresses. The former refers to the stress established during bolt installation and the latter is mobilized when the bolt tends to slip in the borehole owing to the roughness of the borehole surface. The existing analysis of the inflatable rock bolt does not appropriately describe the interaction between the bolt and the rock since the influence of the folded tongue of the bolt on the stiffness of the bolt and the elastic rebound of the bolt tube in the end of bolt installation are ignored. The interaction of the inflatable bolt with the rock is thoroughly analysed by taking into account the elastic displacements of the rock mass and the bolt tube during and after bolt installation in this article. The study aims to reveal the influence of the bolt tongue on the contact stress and the different anchoring mechanisms of the bolt in hard and soft rocks. A new solution to the primary contact stress is derived, which is more realistic than the existing one in describing the interaction between the bolt and the rock. The mechanism of the secondary contact stress is also discussed from the point of view of the mechanical behaviour of the asperities on the borehole surface. The analytical solutions are in agreement with both the laboratory and field pullout test results. The analysis reveals that the primary contact stress decreases with the Young’s modulus of the rock mass and increases with the borehole diameter and installation pump pressure. The primary contact stress can be easily established in soft and weak rock but is low or zero in hard and strong rock. In soft and weak rock, the primary contact stress is crucially important for the anchorage of the bolt, while in hard and strong rock it is the secondary contact stress that plays a vital role.     

济阳拗陷东营凹陷盐岩中的烃类包裹体 及其地质意义

本文报道在东营凹陷盐岩中发现大量烃类包裹体,这证实盐岩曾经失去封闭能力,成为油气运移通道。在对其盐水包裹体进行均一温度测试时发现,由于捕获压力与实验环境压力差异很大,再加上岩盐在水中溶解度随温度升高而增大,导致测温过程盐水包裹体体积变化和拉伸效应明显,所以同期盐水包裹体的均一温度出现较大波动,结果也不可靠,而纯烃类包裹体在一定程度上可以避免溶解度变化的影响,其均一温度有一定指示意义。通过对岩盐中的烃类包裹体均一温度初步校正,结合埋藏史和热史分析,认为至少存在两期与盐岩层变形有关的烃类流体活动,活动时期分别在东营期和明化镇期。流体对岩盐颗粒滑动和盐岩层变形有极其重要的影响,重结晶的岩盐晶体及其中的流体包裹体是流体作用的直接证据。盐岩中的流体来源、运移方向、活动期次和流体作用下的盐岩变形温度和压力是需要解决的关键问题,这对于了解含油气盆地中盐岩层对油气成藏的控制作用有重要意义。