关于粘土岩崩解，泥化机理的讨论

分析研究了水利，采矿，地下等工程中常见的粘土岩，泥岩等的泥化，及开挖暴露后的吸水崩解现象，讨论了粘土岩等泥化及崩解的物理化学和力学作用机理，特别是对含胀缩性蒙脱石矿物的粘土岩，还从粘土岩的力学强度特性讨论了他们的泥化崩解问题，系统深入地阐述了粘土岩等泥化，崩解机制。     

天然气盖层实验研究及评价

盖层是烃类聚集的必要条件.排替压力则是评价盖层的关键参数.本文主要通过泥质岩的实验研究,着重分析了突破压力与突破时间的关系。根据它们之间一定的函数关系.提出了求取岩石排替压力的方法,并且通过实验和实际资料的研究提出了盖层分级评价的标准。     

砂类土体隧道围岩压缩模量的试验研究

砂类土的压缩模量与砂类土体隧道嗣岩稳定性有较大的关系.从影响砂类土体隧道嗣岩稳定性因素及围岩稳定性分级的角度出发,探讨了与砂类土体隧道围岩稳定性相关的压缩模量的影响冈素,发现砂类土的细粒(d<0.074 mm)含量对其压缩模量有较显著的影响,二者呈负相关;砂类土的相对密实度并非完全足越人而压缩模量也越大,还与细粒含量及细粒含水状态仃关:采用砂类上细粒含水率而不是砂类土含水率的方法来评定潮湿砂类土的压缩模量,得出了细粒含水率对砂类土压缩模量的影响规律.根据细粒含量和相对密实度对压缩模量的影响规律,提出了两指标的分级界限.     

双组份岩石压缩系数推导与试验验证

岩石压缩系数一直是油藏工作者研究的热点问题,近年来黏土矿物的特殊性质对岩石压缩系数的影响已成为人们关注的重点。将岩石视为“骨架+黏土”的双组份模型,从岩石压缩系数定义出发,运用弹性力学理论,推导出双组份岩石压缩系数公式,得到岩石压缩系数与黏土含量及黏土力学性质的理论关系。以大牛地气田含黏土砂岩为对象,通过岩石变内压三轴压缩试验实测岩石压缩系数,并同时进行岩石的微观试验研究。计算出双组份压缩系数公式及其他几种不考虑黏土的传统压缩系数求解方法对应的岩石压缩系理论值,将理论值与岩石压缩系数实测值进行对比分析,结果发现,双组份岩石压缩系数理论值与实测结果更接近,说明了考虑黏土影响的双组份岩石压缩系数理论的合理性,该理论为油气储层岩石压缩系数的预测开拓了新的思路。     

粘土矿物对有机质生烃的催化作用

烃源岩的有机质主要以有机粘土复合体的形式存在。有机质生烃是一种有机粘土化学反应。反应过程中,有机质与粘土之间存在质子和电子迁移,粘土通过对水分子的吸附和离解为有机质加氢裂解提供H+,而有机质生成的有机酸激活了粘土的催化活性,也为蒙皂石伊利石化反应创造了条件。烃源岩不同粘土矿物的选择性催化特征是影响油气组成的最重要因素。粘土的催化活性大小和发育时间是决定烃源岩生烃潜力大小的因素。由于烃源岩在蒙皂石伊利石化阶段具有最大的催化活性,而且与有机质生烃反应同步,因此富含伊$蒙混合层的烃源岩是世界含油气盆地的最有利烃源岩。不同地质时期的烃类地质储量与烃源岩膨胀性粘土的丰度有密切关系。     

Influence of discontinuities and clay minerals in their filling materials on the instability of rock slopes

To assess the influence of discontinuities and clay minerals in their filling materials on the instability of rock slopes, seven rock slopes along the margin of Ganjnameh–Shahrestaneh Road, Hamedan Province, Western Iran were selected, and the physical and mechanical properties of their rocks and discontinuities were determined. By statistical studies of the discontinuities, rock slope stability analysis has been performed using kinematic and limit equilibrium methods so that safety factors for the rock slopes can be calculated. Also, sampling of filling materials and X-ray diffraction tests have been done to identify the clay minerals in the filling materials. The lithologies of the studied rock slopes are granite, diorite and hornfels. The presence of discontinuities and weakness planes with different orientations and clay minerals in filling materials of discontinuities are effective factors that cause plane, wedge and toppling failures in the rock slopes. Clay minerals as filling materials of discontinuities in the studied rock slope facilitate their instability by two different methods. First, absorption of water by infilling clay minerals causes the friction angle of discontinuity surfaces that leads to plane and wedge failures to be reduced. Second, water absorption causes the swelling of clay infilling minerals that leads to toppling failure.     

晋北罕见的“烧变高岭岩”研究

晋北大同及浑源一带,在上石炭世太原统四号煤系中,常见有洁白色的粘土岩,外貌酷似“人工熟料”,其成因与煤层的自燃作用有关。由于原岩主要矿物为高岭石故命名这种洁白色的粘土岩为“烧变高岭岩”。     

Constitutive Relationships for Elastic Deformation of Clay Rock: Data Analysis

Geological repositories have been considered a feasible option worldwide for storing high-level nuclear waste. Clay rock is one of the rock types under consideration for such purposes, because of its favorable features to prevent radionuclide transport from the repository. Coupled hydromechanical processes have an important impact on the performance of a clay repository, and establishing constitutive relationships for modeling such processes are essential. In this study, we propose several constitutive relationships for elastic deformation in indurated clay rocks based on three recently developed concepts. First, when applying Hooke’s law in clay rocks, true strain (rock volume change divided by the current rock volume), rather than engineering strain (rock volume change divided by unstressed rock volume), should be used, except when the degree of deformation is very small. In the latter case, the two strains will be practically identical. Second, because of its inherent heterogeneity, clay rock can be divided into two parts, a hard part and a soft part, with the hard part subject to a relatively small degree of deformation compared with the soft part. Third, for swelling rock like clay, effective stress needs to be generalized to include an additional term resulting from the swelling process. To evaluate our theoretical development, we analyze uniaxial test data for core samples of Opalinus clay and laboratory measurements of single fractures within macro-cracked Callovo-Oxfordian argillite samples subject to both confinement and water reduced swelling. The results from this evaluation indicate that our constitutive relationships can adequately represent the data and explain the related observations.     

西南喀斯特地区不同石漠化阶段土壤黏土矿物组成及其含量变异研究

为了探索西南喀斯特地区土壤中黏土矿物组成及其含量的变异规律,以贵州省普定县和荔波县不同石漠化阶段典型土壤的黏土矿物为例,采用x-射线衍射仪图谱分析方法,计算得到黏土矿物组成及其含量,探讨不同石漠化阶段黏土矿物组成变化规律及其含量之间的线性关系。结果表明：不同石漠化阶段黏土矿物的组成是相同的,均为高岭石、蒙脱石和伊利石;在未石漠化、轻度石漠化、中度石漠化阶段,蒙脱石在剖面表层的质量分数分别为27．82％、29．34％、58．32％,高岭石分别为21．39％、31．81％、36．93％,伊利石分别为50．79％、38．85％、4．75％;在西南喀斯特地区,各石漠化阶段伊利石与蒙脱石的含量之间以及伊利石和高岭石的含量之间都呈显著的线性相关,相关系数分别为-0．9703、-0．9456;西南喀斯特地区土壤相似的成土作用和成土环境造成了黏土矿物相同的组成,而黏土矿物含量的差异说明各成土作用的程度或阶段是不同的;粉粒中的黏土矿物主要为石英和白云母,而砂砾中的黏土矿物主要为石英。     

试论碳酸盐岩天然气地球化学的研究方向

虽然多年来油气勘探的实践说明碳酸盐岩可以成为烃源岩，但对于碳酸盐岩的成烃机理和评价标准尚无定论。作者认为，这主要是碳酸盐岩的生烃过程与泥岩的重烃过程不同引起的：碳酸盐岩一般先成岩而后生烃，泥岩一般则先生烃而后成岩。作者根据四川盆地碳酸盐岩天然气地球化学的研究现状，提出今后碳酸盐岩油气地球化学研究的主要方向有：1、碳酸盐岩烃源岩生烃机理研究；2、碳酸盐岩天然气有效运聚系统研究；3、碳酸盐岩气藏地球化学研究，并提出了相应的主要研究内容。     

华北晚古生代煤系I／S间层粘土岩稀土元素地球化学特征

通过ICP和INAA方法对华北几个晚古生代煤田（煤矿区）的I／S间层粘中土岩样品进行了稀土元素（REE）地球化学特征研究。结果表明，无序间层粘土岩REE含量较低，并具中－－弱Eu正异常为特征；IS有序间层粘岩以REE含量高，中－－强Eu亏损为特征，两种I／S间层粘土岩的REE含量及特征均与NASC有所不同，物源分析表明，无序间层粘土岩主要由中性火山碎屑（岩）在原地蚀变、转化而成，而有序间层粘土岩则是由酸性岩蚀变而成。     

砒砂岩岩性特征对抗侵蚀性影响分析

砒砂岩区是黄河中游集中的基岩产沙区,强烈的岩土侵蚀与砒砂岩的岩性密切相关。通过对砒砂岩原状样品的矿物组成、微结构的测试和定量分析表明:砒砂岩中岩石矿物的组成特征是以不稳定、易风化、亲水性强的粘土矿物为主;岩石微结构特征表现为颗粒大小悬殊、排列无序、孔隙发育、胶结物为粘土矿物,影响岩石的物理力学性质,降低了砒砂岩的抗风化、抗侵蚀性能。     

黔中—渝南岩溶型铝土矿含矿岩系特征、控制条件及生成发展模式

早石炭世九架炉组与晚石炭世大竹园组,皆属黔中—渝南岩溶型铝土矿含矿岩系。按岩溶形态组合特征,主要可分为溶蚀洼地型和岩溶湖泊型,两种类型的含矿岩系下段,皆以铁质黏土岩、绿泥石黏土岩为主,间夹赤铁矿层,时夹白云岩、石灰岩透镜体,二者均为永久性、低能、浅水、海源湖泊沉积产物。溶蚀洼地型含矿岩系上段的铝土矿、铝土岩和黏土岩等,皆产于陆地上各种形态的溶蚀洼地中。岩溶湖泊型含矿岩系上段的各种铝土矿、铝土岩和黏土岩等,皆为间歇性、洪控、高能、浅水、陆源湖泊中沉积而成的。因距海较近,在海泛和强风暴潮的影响下,含矿岩系上段的陆相沉积物中时显海相、过渡相沉积特征。在赤道附近有利的地质、气候、水文、植物等条件下,母岩经红土化形成的风化壳物质,被流水短距离搬运到溶蚀洼地和岩溶湖泊中,沉积形成的岩溶型铝土矿含矿岩系,是在同一时间段内连续发生、发展和演化的过程, 其间没有明显的间断时期。     

黔中—渝南岩溶型铝土矿含矿岩系特征、控制条件及生成发展模式

早石炭世九架炉组与晚石炭世大竹园组,皆属黔中—渝南岩溶型铝土矿含矿岩系。按岩溶形态组合特征,主要可分为溶蚀洼地型和岩溶湖泊型,两种类型的含矿岩系下段,皆以铁质黏土岩、绿泥石黏土岩为主,间夹赤铁矿层,时夹白云岩、石灰岩透镜体,二者均为永久性、低能、浅水、海源湖泊沉积产物。溶蚀洼地型含矿岩系上段的铝土矿、铝土岩和黏土岩等,皆产于陆地上各种形态的溶蚀洼地中。岩溶湖泊型含矿岩系上段的各种铝土矿、铝土岩和黏土岩等,皆为间歇性、洪控、高能、浅水、陆源湖泊中沉积而成的。因距海较近,在海泛和强风暴潮的影响下,含矿岩系上段的陆相沉积物中时显海相、过渡相沉积特征。在赤道附近有利的地质、气候、水文、植物等条件下,母岩经红土化形成的风化壳物质,被流水短距离搬运到溶蚀洼地和岩溶湖泊中,沉积形成的岩溶型铝土矿含矿岩系,是在同一时间段内连续发生、发展和演化的过程, 其间没有明显的间断时期。     

岩溶区隧道围岩--支护体系稳定性研究

岩溶是地下水地质作用的过程和结果，是隧道建设面临的不良地质现象之一。正在建设中的某高速公路隧道出口段岩溶地质作用强烈，溶隙、孔洞发育，且受构造变形及后期淋滤溶蚀作用强烈，力学强度低，岩性复杂。其角砾状粘土岩和水云母粘土岩多已泥化成粘土，遇水易膨胀。岩溶区隧道围岩——支护体系的稳定性是该隧道建设面临的主要问题。文章结合隧道施工过程中的围岩变形监控量测和三维弹塑性有限元数值仿真模拟对隧道围岩——支护体系的稳定性进行了研究。围岩水平收敛和拱顶下沉位移及速率变化特性表明，在监测时段内隧道围岩无趋于稳定的迹象。施工动态力学数值仿真模拟表明，在初期支护条件下，围岩出现了较大范围的塑性破坏区，两隧道之间(间距45．0m)围岩破坏接近度达到0．70，最大竖向位移达到3．0mm，表明隧道全断面施工时，两隧道相互作用影响程度较大。为确保隧道围岩——支护体系的稳定，选择合理的施工方法，制定切实可行的支护方案提供了信息。     

黔西北上二叠统峨眉山玄武岩风化壳中铌富集机制初探

近年越来越多的研究显示,贵州西北一带的峨眉山玄武岩风化壳上存在一套富铌、锆、钛、镓、稀土的多金属矿层,主要与风化壳中的黏土岩有关,不过,其中有关铌的赋存状态和富集机制仍有待研究.文章对黏土岩物质来源做出厘定,认为风化壳黏土岩层主要来源于高钛的峨眉山玄武岩,铌、锆、稀土等元素也继承自玄武岩.铌主要赋存于铁铝质黏土岩中(w...     

Crack Initiation and Crack Propagation in Heterogeneous Sulfate-Rich Clay Rocks

Brittle fracture processes were hypothesized by several researches to cause a damage zone around an underground excavation in sulfate-rich clay rock when the stress exceeds the crack initiation threshold, and may promote swelling by crystal growth in newly formed fractures. In this study, laboratory experiments such as unconfined and confined compression tests with acoustic emission monitoring, and microstructural and mineralogical analyses are used to explain brittle fracture processes in sulfate-rich clay rock from the Gipskeuper formation in Switzerland. This rock type typically shows a heterogeneous rock fabric consisting of distinct clayey layers and stiff heterogeneities such as anhydrite layers, veins or nodules. The study showed that at low deviatoric stress, the failure behavior is dominated by the strength of the clayey matrix where microcracks are initiated. With increasing deviatoric stress or strain, growing microcracks eventually are arrested at anhydrite veins, and cracks develop either aligned with the interface between clayey layers and anhydrite veins, or penetrate anhydrite veins. These cracks often link micro-fractured regions in the specimen. This study also suggest that fracture localization in sulfate-rich clay rocks, which typically show a heterogeneous rock fabric, does not take place in the pre-peak range and renders unstable crack propagation less likely. Sulfate-rich clay rocks typically contain anhydrite veins at various scales. At the scale of a tunnel, anhydrite layers or veins may arrest growing fractures and prevent the disintegration of the rock mass. The rock mass may be damaged when the threshold stress for microcrack initiation is exceeded, thus promoting swelling by crystal growth in extension fractures, but the self-supporting capacity of the rock mass may be maintained rendering the possibility for rapidly propagating instability less likely.     

泥质岩成岩作用中的黏土矿物研究

文章通过对泥质岩的黏土质矿物组分、成岩作用中黏土质矿物变化综合研究,认为泥质岩中存在大量黏土矿物,且泥质沉积物由松散到固结成岩实质上是黏土矿物组成的变化。泥质岩中主要黏土矿物包括高岭石、蒙皂石、绿泥石、伊利石以及其组成的混层型矿物伊利石/蒙皂石、绿泥石/蒙皂石,其成岩过程可划分为成岩早期的压实阶段、成岩晚期的黏土矿物转化阶段。压实阶段的泥质沉积物中黏土矿物具有物源的继承性、沉积水体古环境指示意义;受压实作用孔隙水、层间水被排出,原生絮凝团被压破,使片状质点趋于平行排列,黏土矿物与孔隙水发生反应,亦形成少量的新生作用矿物,因而黏土矿物具继承源和新生作用源特性。成岩晚期阶段发生层间水释放及层间阳离子交换,从而使得矿物晶体结构与成分发生变化,主要表现为一元黏土矿物向二元混层型转化,最后再到一元型黏土矿物的转化,最终形成转变源黏土矿物。     

Models of rock varnish formation constrained by high resolution transmission electron microscopy

Nanometre-scale transmission electron microscope imagery of manganiferous rock varnishes from Death Valley, California, Peru, Antarctica, and Hawaii confirms prior infrared mineralogy studies. The building blocks of rock varnish are clay minerals that are cemented to the rock by oxyhydroxides of manganese and iron. Rock varnish is layered on the scale of nanometres, with the basic structure defined by the subparallel alignment of detrital clay minerals. Although only a few examples of bacteria were found, possible cell-wall encrustations are ubiquitous and aligned with the clay minerals. Mn–Fe oxides appear to be mobilized from bacterial casts and then reprecipitate on clay minerals that weather into monolayers. These observations have implications for varnish dating and palaeoenvironmental techniques: K–Ar and uranium-series dating of rock-varnish oxides can only yield minimum ages; however, this small spatial scale of mobilization would not alter the signal from micron-scale microchemical laminations.     

胶结砂及半成岩粘土的岩土力学特征分析--以湘阴湘江大桥桥位区为例

胶结砂及半成岩粘土目前处于一种由土向岩石转化的状态，它们和正常意义上的土及岩石均有明显的区别，在组成、结构和构造等方面，它们既具有部分土的特征，又具有部分岩石的特征，本文对湘阴湘江大桥桥位区产出的胶结砂及半成岩粘土的土力学和岩石力学特征进行了分析，对其成因和应用进行了探讨。