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。     

中国昆明地区岩溶洞穴洞口带苔藓植物研究

为了研究中国西南岩溶洞穴植物区系与生物多样性特征, 作者曾两次对云南昆明地区12个岩溶洞穴进行了野外考察和苔藓植物标本采集工作。其中含昆明市石灰岩洞穴1个, 石林县石灰岩洞穴5个和宜良县白云岩洞穴6个。根据采自12个岩溶洞穴洞口带的164件苔藓植物标本研究, 本文首次报道昆明地区洞穴苔藓植物10科18属25种。昆明地区洞穴中分布较多的苔藓植物科有丛藓科( Po ttiaceae) 5属8种,凤尾藓科( Fi ssidentaceae ) 1属4种,柳叶藓科( Amblystegiaceae ) 3 属3 种和青藓(Brachytheciaceae ) 2属3种。溶洞中较常见的4种苔藓植物种类是萤光苔类植物光苔Cyathodiumcavernarum Kunze ( 见于6个溶洞中) , 小凤尾藓Fissidens bryoides Hedw ( 见于4个溶洞中) , 橙色净口藓Gymnostonum calcareum Nees et Ho rsch (见于3 个溶洞中)和长叶扭口藓Tortella tortuosa( Hedw ) Limp ( 见于3个溶洞中)。野外观察表明,受洞穴弱光环境生态因子的限制, 昆明地区洞穴苔藓植物主要生长于洞穴洞口0～ 26m带范围内; 2种丛集型藓类植物, 橙色净口藓Gymnostonumcalcareum Nees et Horsch, 和钩喙净口藓G.recurvirost re Hedw 参与洞口带钟乳石或石笋钙华沉积。      

Analysis on the deployment of mining research supported by the grant program of Deep Resources Exploration and Mining

The Deep Resources Exploration and Mining(DREAM) grant program, within the framework of The National Key Research and Development Program grants, is a pillar to implement China's science and technology strategy in the area of deep resources exploitation. To tackle the insufficient of theories and technologies for the 1000-meter-deep mining, a section of mining, covering the research of basic theories, general technologies and application demonstration, was arranged in the layout of DREAM under the principle of "whole chain design, integrated implementation". In the aspect of basic research, DREAM mainly focused on the deep rock mechanics and mining theory, such as the in-situ mechanical behavior of deep rock, deep high stress induction and energy regulation theory. For the general and key technologies, DREAM supported the research on the mine construction and hoisting, excavation, rock breaking, mining methods and mining safety according to the characteristics of coal and metal mines. For the demonstration application, taking green, safe and efficient as the starting point, DREAM aimed at the green, safe and high efficiency mining, and the demonstration and leading role projects such as the low-waste and high-efficiency back fill mining. Since 2016, 10 RD projects have been funded, and 122 institutional participants with a total budget of RMB 235 million from the central government and RMB 480 million from enterprises as well as local governments have been involved. It is expected that the mining section of DREAM would contribute to establishing the theory and technology system in the area of deep mining and promoting the ability of deep resource exploitation in China.     

Principles of Probabilistic Regional Mineral Resource Estimation

Five principal sources of uncertainty in quantitative mineral resource estimation are listed and illustrated by means of a simple example (mosaic model) and a case history study for large copper deposits in the Abitibi area of the Canadian Shield. Abitibi copper potential originally was estimated on the basis of 1968 estimates of production and reserves totalling 3.12 Mt Cu. This prognostication now could be evaluated on the basis of 2008 copper production and reserves totalling 9.50 Mt Cu. An earlier hindsight study performed on the basis of 1977 data (totalling 5.23 Mt Cu) showed seven new discoveries occurring either in the immediate vicinities of known deposits or on broad regional copper anomalies predicted from the 1968 inputs. By 1977, the global geographic distribution pattern of large copper deposits in the Abitibi area had stabilized. During the next 30 years, new copper was essentially found close to existing deposits, much of it deeper down in the Earth's crust. In this paper, uncertainties associated with copper ore tonnage are analyzed by comparison of 2008 data with 1968 data using (a) log-log plots of size versus rank, and (b) lognormal QQ-plots. Straight lines fitted by least squares on these plots show that 1968 slopes provide good estimates of 2008 slopes but 1968 intercepts are much less than 2008 intercepts. In each linear log-weight versus log-rank plot, the slope is related to fractal dimension of a Pareto frequency distribution, and in a lognormal QQ-plot it is determined by logarithmic variance. The difference between 2008 and 1968 intercepts represents the increase in copper ore production and reserves from 1968 to 2008. The Pareto model fits actual copper and massive sulphides increase over the past 40 years better than the lognormal frequency distribution model for 10 km×10 km cells on favorable environments in the Abitibi area.      

Application of 3D Static Modelling in Reservoir Characterization: A Case Study from the Qishn Formation in Sharyoof Oil Field, Masila Basin, Yemen

Three-dimensional(3 D)static modelling techniques are applied to the characterization of the Qishn Formation(Fm.)in the Sharyoof oil field locating within the Masila basin,southeastern Yemen.The present study was initiated by the seismic structural interpretation,followed by building a 3 D structural framework,in addition to analysing well log data and from these,3 D facies and petrophysical models are constructed.In the Sharyoof oil field,the Qishn Fm.exhibits depth values within the range of 400-780 m below sea level,with a general increase towards the SSE.A set of high dip angle normal faults with a general ENE-WSW trend dissect the rocks.The strata are also folded as a main anticline with an axis that is parallel to the fault trend,formed as a result of basement uplift.According to the facies models,the Qishn Fm.comprises 43.83% limestone,21.53% shale,21.26% sandstone,13.21% siltstone and 0.17% dolomite.The Qishn Carbonates Member has low porosity values making it a potential seal for the underlying reservoirs whereas the Upper Qishn Clastics SI A and C have good reservoir quality and SIB has fair reservoir quality.The Upper Qishn Clastics S2 and S3 also have fair reservoir quality,while the Lower Qishn Clastics zone has good reservoir quality.The water saturation decreases towards the west and east and increases towards north and south.The total original oil in-place(OOIP)of the Upper Qishn clastics is 106 million STB within the SI A,SIC and S2 zones.Drilling of development wells is recommended in the eastern study area,where good trapping configuration is exhibited in addition to the presence of a potential seal(Upper Qishn Carbonates Member)and reservoir(Qishn Clastics Member)with high porosity and low water saturation.     

印度共和国地质构造与区域成矿

印度共和国位于南亚次大陆中部,陆地面积297.32万km2(不包括印控克什米尔地区与锡金),北部为喜马拉雅高山区,海拔平均为5500m;中部是印度河-恒河-布拉马普特河(在中国境内称雅鲁藏布江)平原,平均海拔100~200m,是印度经济最发达、人口最稠密地区;南部是印度半岛高原区,西高东低,     

多年冻土环境对寒区天然气管线稳定性的影响

Field investigations of several gas mains in different geosystems were carried out in Noviy Urengoy region (Eastern Siberia) in September, 2003. There were on ground pipelines covered with peat or sand. In case of small rivers pipelines were elevated by pile support on the shores. Because pipelines were applied in cryolithozone that means special secure methods used in pipeline systems functioning and operating. There are multiple sites of natural landscapes destructed or totally destroyed during building and exploiting of the pipelines. That causes negative cryogenic processes development. The most dangerous one is the heaving, that reaches up to several meters in humid landscapes. The complex thermoerosion, thermokarst and heaving occur very often at one site. The heaving of piles leads to pipe deformations and the emergency situations to occur. It is possible to predict negative cryogenic processes development and so far to reduce an emergency risk.     

Magmatic and hydrothermal zircon growth during multiple orogenic cycles in an evolving mantle wedge

The Hongseong area of the Hongseong-Imjingang Belt in the central-western Korean Peninsula forms part of a subduction-collision system that is correlated with the Qinling-Dabie-Sulu Belt in China. Several serpentinized ultramafic bodies carrying blocks of metamorphosed mafic rocks occur in this area. Here we investigate zircon grains in serpentinites from Bibong(BB) and Wonnojeon(WNJ), and high-pressure(HP) mafic granulite from Baekdong(BD) localities based on U-Pb, REE and Lu-Hf analyses. The zircons from BD HP mafic granulite show distinct age peaks at 838 Ma, 617 Ma and 410 Ma, with minor peaks at1867 Ma, 1326 Ma and 167 Ma. The Neoproterozoic age peaks in these rocks as well as in the serpentinites suggest subduction-related melt-fluid interaction in the mantle wedge at this time. The older zircon grains ranging in age from the Early to Middle Paleoproterozoic might represent detrital grains from the basement rocks transferred to the wedge mantle through sediment subduction. The BD HP mafic granulite shows a Middle Paleozoic age peak(Devonian; 410 Ma). The 242-245 Ma age peaks in the compiled age data of zircon grains serpentinites from BB and WNJ correspond to a major Triassic event that further added melts and fluids into the ancient mantle wedge to crystallize new zircons. In the chondrite normalized rare earth element diagram, the magmatic zircon grains from the studied rocks show LREE depletion and HREE enrichment with sharply negative Eu and Pr anomalies and positive Ce and Sm anomalies. The REE patterns of hydrothermal zircons show LREE enrichment, and relatively flat patterns with negative Eu anomaly. Zircon Hf signature from the WNJ serpentinite show negative εHf(t)(-18.5 and-23.5) values indicating an enriched mantle source with TDM in the range of 1614 Ma and1862 Ma. Zircons from the BD HP mafic granulite also show slightly negative εHf(t)(average-4.3) and TDM in the range of 1365-1935 Ma. Our study provides evidence for multiple zircon growth in an evolving mantle wedge that witnessed melt and fluid interaction during different orogenic cycles.     

Advanced reliability analysis of slopes in spatially variable soils using multivariate adaptive regression splines

This study aims to extend the multivariate adaptive regression splines(MARS)-Monte Carlo simulation(MCS) method for reliability analysis of slopes in spatially variable soils. This approach is used to explore the influences of the multiscale spatial variability of soil properties on the probability of failure(P_f) of the slopes. In the proposed approach, the relationship between the factor of safety and the soil strength parameters characterized with spatial variability is approximated by the MARS, with the aid of Karhunen-Loeve expansion. MCS is subsequently performed on the established MARS model to evaluate Pf.Finally, a nominally homogeneous cohesive-frictional slope and a heterogeneous cohesive slope, which are both characterized with different spatial variabilities, are utilized to illustrate the proposed approach.Results showed that the proposed approach can estimate the P_f of the slopes efficiently in spatially variable soils with sufficient accuracy. Moreover, the approach is relatively robust to the influence of different statistics of soil properties, thereby making it an effective and practical tool for addressing slope reliability problems concerning time-consuming deterministic stability models with low levels of P_f.Furthermore, disregarding the multiscale spatial variability of soil properties can overestimate or underestimate the P_f. Although the difference is small in general, the multiscale spatial variability of the soil properties must still be considered in the reliability analysis of heterogeneous slopes, especially for those highly related to cost effective and accurate designs.     

Analysis on the law of occurrence of shallow geothermal energy in Zhoukou City of Henan Province,China

In this paper,through data collection and field investigation,the development and utilization status of shallow geothermal energy in Zhoukou urban area was discussed.Based on the analysis of hydrogeological conditions,rock and soil structure characteristics and field test research,the spatial distribution characteristics of rock and soil in the study area were summarized.The study shows that Zhoukou City is located in the alluvial plain of Huanghuai,and the loose deposits of river alluvial genesis range 0-200 m.These loose deposits and groundwater stored in their pores are the main carriers of shallow geothermal energy.In the central part of the Yinghe River in the middle of the study area,the aquifer thickness is within 200 m,the particle size is coarser,the water-bearing degree and recharge capacity is better.On this basis,the paper uses AHP to evaluate the suitability of shallow geothermal energy development and utilization to guide the rational development and utilization of shallow geothermal energy resources.     

不同支护结构的桩身应力及其分析

钻孔灌注桩悬臂支护结构和单层支点混合支护结构是常用的深基坑支护结构型式,钻孔灌注桩连拱式组合拱结构是一种新型的支护结构型式。通过对南京某大厦深基坑开挖过程中,桩身应力的实测研究和对比分析,获得了在相同的工程水文地质、施工和降水条件下,3种不同支护结构的受力主筋在不同深度的应力大小及其分布形态,为设计计算和钻孔灌注桩连拱式组合拱结构的推广应用积累了宝贵资料。     

多级支挡结构地震主动土压力的极限分析

多级组合支挡结构形式在高边坡防护工程中得到了广泛采用,但现有研究却较少涉及这种支挡结构形式的地震土压力计算问题。应用拟静力法和塑性极限分析上限定理,并且基于强度折减技术,推导了重力式挡墙与两级锚杆挡墙组合支挡结构形式的地震主动土压力及其系数的上限解。该上限解考虑了水平和竖向地震系数、墙背倾角、坡面形式及多级支护方式、土体黏聚力、土体与墙背的黏附力等诸多因素。二级锚杆挡墙实例分析表明：静力条件下主动土压力计算值与现有相关方法的计算结果一致,土的抗剪强度折减系数、上挡墙锚杆轴力等参数,对下挡墙地震主动土压力影响显著。二级组合支挡结构地震主动土压力影响参数敏感性分析表明：水平地震系数以及重力式挡墙墙高和倾角的敏感性较大,上挡墙锚杆的轴力和倾角等参数的敏感性相对较小     

格宾挡墙发展综述

格宾挡墙是一种新型柔性支挡技术,且优于以往传统方法,具有柔性、透水性、耐用性、抗震性以及利于植被生长等优点。近年来逐渐在我国水利、航道、公路、铁路、矿业、地灾、机场等工程建设中广泛应用。回顾了格宾挡墙发展历程,分析了现阶段格宾挡墙的双绞合六边形钢丝网和多种不同填料的界面摩擦特性、格宾挡墙的破裂面形式、加筋格宾挡墙的加筋机理、加筋格宾挡墙最佳布筋方式等研究热点。最后,探讨了格宾挡墙研究理论滞后、设计规范缺失等问题,并提出了对策。     

坑中坑挡土墙变形内力分析

现代基坑工程中出现坑中坑的情况越来越普遍,设计需要对坑中坑的桩墙围护进行结构分析。坑中坑的外围基坑与内部基坑的桩墙存在相互影响,因此,坑中坑的桩墙围护结构受力分析相对而言更加复杂。针对这种坑中坑内、外桩墙的复杂受力情况,提出了坑中坑桩墙围护结构的弹性支点法联合求解模型,通过对内、外桩墙间有限土体的地基弹簧刚度的求解,使该模型可以解决坑中坑桩墙的内力变形计算问题。具体的坑中坑工程实例分析表明,采用弹性支点法联合求解模型得到的围护结构变形、内力与工程实际比较吻合,研究成果具有一定理论与工程实用意义。     

齿坎式挡土结构物极限抗滑力研究

以齿坎式挡土结构物现场抗滑试验为研究对象,运用强度折减的有限元方法,研究了齿坎长度分别为0、0.7、1.0 m的挡土结构物的极限抗滑力和齿坎式挡土结构物的滑动破坏模式,以及位于软弱地基中齿坎在挡土结构物中的抗滑机理,提出了齿坎式挡土结构物的综合稳定性安全系数的概念。研究表明：理论研究结果能很好地表征现场试验成果;随着齿长的增加,齿坎式结构物由滑移破坏转变为倾覆破坏;强度折减的有限元方法进行挡土结构物的极限设计是完全合理的,该方法可应用于齿坎式挡土结构物的工程设计中。     

改进的杆系有限元在预应力锚杆柔性支护法中应用

现在基坑设计中常用的杆系有限元计算方法是基于桩墙和锚杆联合支护的,不适用于预应力锚杆柔性支护。根据预应力锚杆柔性支护法的施工特点,改进了杆系有限元计算模型,提出柔性支护的开挖荷载计算方法,使之可以适用于预应力锚杆柔性支护法。编制了相应的计算程序,最后对一个实际工程进行计算分析,结果表明,用改进后的杆系有限元方法可以计算出预应力锚杆柔性支护的基坑水平位移、锚杆轴力,计算值与实测值较为吻合。     

基于尖点突变理论的浆砌块石边坡稳定性研究

根据影响浆砌块石挡土墙边坡稳定性的主要控制变量：挡土墙的垂直度i、挡土墙高度h、填料的内摩擦角 、墙后边坡土的重度 、土对挡土墙基底的摩擦系数 、土对挡土墙墙背的摩擦角 等6个因素变量,利用正交设计原理优化试验设计方案,结合库仑理论与力的多边形法,分析计算浆砌块石挡土墙边坡的安全系数,最后用尖点突变理论的突变级数法进一步判断边坡的稳定性。研究结果表明：影响挡土墙边坡稳定性的6个主要控制变量因素的主次关系为 ;在分析挡土墙边坡稳定性时,采用突变级数法进行计算判断,可以直观地判断边坡的稳定情况,从而弥补工程中运用传统的最小安全系数法进行判断出现的模糊不确定的情况。     

圆形支护结构的拱效应等效支撑计算方法

从弹性力学中圆筒受均布荷载的解出发,把圆形支护结构作为弹性地基梁,把圆形支护结构的拱效应作为支护结构的等效支撑作用在弹性地基梁上,从而得出了一个计算圆形支护结构内力和位移的拱效应等效支撑方法。工程实例的计算表明,该方法是实用而有效的。     

不同面板形式加筋土挡墙结构特性现场试验研究

以成昆铁路复线加筋土挡墙为工程依托进行现场原位试验,对比分析工后9个月内新型整体式面板、内嵌返包结构的模块式面板和模块式面板3类加筋土挡墙的结构特性。在此期间发生两次地震,监测了震后挡墙变形及土压力变化。结果表明:整体式面板加筋土挡墙整体稳定性最好,具有良好的抗震性能,格栅应变变化率、墙体压缩量和墙面水平位移均最小。整体式面板和模块式面板加筋土挡墙墙背土压力沿墙高近似呈M型,内嵌返包结构的模块式面板加筋土挡墙墙背土压力沿墙高近似呈倒S型。整体式面板加筋土挡墙的侧向土压力系数沿墙高变化较小,小于美国联邦公路局(FHWA)加筋设计指南计算值;内嵌返包结构的模块式面板加筋土挡墙侧向土压力系数沿墙高呈增大的趋势,挡墙中、下部小于FHWA计算值,上部接近或大于静止土压力系数;模块式面板加筋土挡墙侧向土压力系数大部分处在FHWA计算值与静止土压力系数之间。3类挡墙土工格栅应变沿墙高均呈非线性变化。挡墙墙体压缩量随着时间的增加逐渐增加,在工后前50 d时间内增加速率较快,随后增加速率减缓,进入雨季之后增加速率再次增大。发生地震后,3类加筋土挡墙均出现不同程度的墙背土压力减小、格栅应变增大、墙体压缩量增加和墙面板外移的现象。     

改进的主动土压力计算方法

墙背土压力分布与挡土墙的位移大小和转动模式密切相关。针对绕墙底向外转动的刚性挡土墙,基于土压力形成机制的分析及已有的研究成果,建立挡土墙位移与墙背土体内摩擦角发挥值之间的关系式,反映了墙背土体内摩擦角随着挡土墙位移的增加而渐进发挥的过程。在此基础上,提出一种改进的考虑位移影响的主动土压力计算方法。计算结果表明,随着挡土墙位移的增大,墙背土压力由静止土压力逐步减小。当挡土墙位移达到临界值后,相应的墙背土压力均收敛于库仑主动土压力。墙底背面土压力也是随着挡土墙位移的增长而逐步收敛于库仑主动土压力。与模型试验结果对比表明,理论计算值与试验实测值基本吻合。