Volume and Surface Distribution Heterogeneity of Nano-pore in Coal Samples by CO2 and N2 Adsorption Experiments

In this paper, the heterogeneity of adsorption pores in middle and high rank coal samples were analyzed by using low temperature N2 and CO2 adsorption technology and fractal theory. The following results were achieved. 1) According to the results of volume and surface fractal dimension, meso-pores can be classified into Mep-1, Mep-2, and Mep-3, respectively. Micro-pore can be classified into Mip-1, Mip-2, and Mip-3, respectively. 2) Pore types play an important role in affecting the heterogeneity of meso-pores. The volume heterogeneity (VHY) of Mep-1 is simpler than that of Mep-2 and Mep-3 in type A samples. However, the VHY of Mep-1 becomes gradually larger than that of Mep-2 and Mep-3 from type A to type B and C. The VHY of open pore in the same diameter is higher than that of semi-open or closed pore. Meanwhile, the surface heterogeneity (SHY) of types A and B samples is significantly larger than that of type C, the SHY of semi-open or closed pores is more complicated than that of open pores. 3) Coal rank mainly affects the heterogeneity of micro-pores. The heterogeneity of type A is always smaller than that of type B and C. The VHY of Mip-1 is more complicated than that of Mip-2 and Mip-3 in the same samples, and the sensitivity of the VHY of Mip-1 and Mip-2 to the degree of coal rank is smaller than that of Mip-3. Meanwhile, the SHY of Mip-1 and Mip-2 is simpler than that of Mip-3 in the same sample, the SHY of micro-pores remains stable as the pore size decreases, and the affect of coalification level on SHY decreases with the decrease in pore diameter. Full-scale fractal characterization has enabled quantitative characterization of adsorption pore properties and provided useful information with regards to the similarity of pore features in different coal reservoirs.     

微动HVSR法在岩溶区探测地下河管道和溶洞的有效性研究

微动HVSR(Horizontal-to-Vertical Spectral Ratio)法是一种简单有效的被动源地震勘探方法,当测点下方介质存在明显的速度变化时,HVSR曲线会呈现相应的异常形态。为探索该方法在岩溶区探测地下河管道和溶洞的有效性,选择桂林毛村地下河流域内的大岩前村作为研究区,并在此开展野外试验。研究区发育有一条地下河管道,通过精准的洞穴测量,获得了此地下河管道的平面位置和洞高等信息。在研究区的地下河管道上方地面布设3条物探测线,均进行微动HVSR法测量,并用探地雷达法测量作对比。结果表明,两种物探方法的异常位置与测线下方地下河管道的实际平面位置基本一致,证明微动HVSR法可作为一种有效的地下河管道和溶洞探测方法。     

贵州水城“7.23”高位远程滑坡冲击铲刮效应分析

以2019年贵州水城“7.23”滑坡为例,采用现场调查、无人机航测和数值模拟技术,分析了滑坡的运动过程和冲击铲刮特征,结果表明:（1）水城“7.23”滑坡属典型的高位远程滑坡,滑体高位启动后冲击下方凸起山脊,铲刮地表残坡积土层,并解体形成碎屑流,最大铲刮深度可达11 m;（2）模拟结果显示,滑坡运动最大速度为30 m?s-1,最大动能达8 900 kJ,铲刮体积达46×104 m3,最终体积为116×104 m3,灾害放大效应明显;（3）水城滑坡的冲击铲刮过程可分为冲击嵌入→剪切推覆→裹挟混合三个阶段。      

隧道变形过程中电磁辐射强度参数的变化规律

根据丽江至香格里拉铁路中义隧道变形及电磁辐射的现场监测资料,对隧道变形过程中的电磁辐射特性及电磁辐射强度极大峰值事件数N、超过强度平均值的极大峰值事件数M与隧道水平收敛变形的关系进行了统计分析。研究表明：（1）电磁辐射最大强度平均值E在初期支护破坏前,随隧道变形的增大而增大,初期支护破坏后,随隧道变形的增大而减少,电磁辐射最大强度平均值先升后降的出现时间与初期支护破坏的时间接近。（2）电磁辐射强度极大峰值事件数、超过强度平均值的极大峰值事件数的波动速率 、 与隧道变形速率呈正线性相关关系;电磁辐射强度极大峰值事件数、超过强度平均值的极大峰值事件数的百分比 、 与隧道累计变形呈正线性相关关系。结论对深化地下洞室变形过程中的电磁辐射特性的认识,提高电磁辐射监测技术的现场应用水平具有指导意义。     

沸石矿物在东北地区黑土地盐碱化土壤改良中的应用

东北黑土地特别是松嫩平原的土地盐碱化趋势正在加剧,对黑土地粮食安全提出了很大的挑战,因此,改良盐碱地土壤成为重要的工作.半干旱气候、地质条件、低洼地形及地下水位等都是引起东北黑土地盐碱化的因素,松嫩平原苏打盐碱地尤为突出,其土壤盐分中主要阳离子为Na⁺,阴离子为CO₃^2-和HCO₃^-,具有高碱化特点.沸石作为离子交换剂和吸附剂,能吸附盐碱土中的钠离子和硫酸根离子等,降低土壤pH值和碱化度,同时可增加土壤对铵根离子、磷酸根离子和钾离子的保持能力,提高养分有效性,对于土壤改良效果显著.但由于沸石改性、用量及时效等各方面的不确定性,因此在今后研究中更应注重因地制宜地利用沸石矿物开展盐碱地土壤改良、加强沸石矿物改性与再生的研究,使其在盐碱地脱盐降碱等方面发挥更大的作用.     

Seepage-heat transfer coupling process of low temperature return water injected into geothermal reservoir in carbonate rocks in Xian County,China

Fracture seepage and heat transfer in the geothermal reservoir of carbonate rocks after the reinjection of low temperature geothermal return water is a complex coupling process,which is also the frontier of geothermal production and reinjection research. Based on the research of cascade comprehensive development of geothermal resources in Beijing-Tianjin-Hebei (Xian County),the carbonate geothermal reservoir of Wumishan formation in the geothermal field in Xian County is investigated. With the development of the discrete fracture network model and the coupling model of seepage and heat transfer,the numerical solution of seepage field and temperature field with known fracture network is reached using the finite element software COMSOL,and the coupling process of seepage flow and heat in carbonate rocks is revealed. The results show that the distribution of temperature field of fractured rocks in geothermal reservoir of carbonate rocks has strong non-uniformity and anisotropy. The fracture network is interpenetrated,which constitutes the dominant channel of water conduction,and along which the fissure water moves rapidly. Under the influence of convective heat transfer and conductive heat transfer,one of the main factors to be considered in the study of thermal breakthrough is to make the cold front move forward rapidly. When the reinjection and production process continues for a long time and the temperature of the geothermal reservoir on the pumping side drops to a low level,the temperature of bedrocks is still relatively high and continues to supply heat to the fissure water,so that the temperature of the thermal reservoir on the pumping side will not decrease rapidly to the water temperature at the inlet of reinjection,but will gradually decrease after a long period of time,showing an obvious long tail effect. The distribution of fractures will affect the process of seepage and heat transfer in carbonate reservoirs,which should be considered in the study of fluid thermal coupling in carbonate reservoirs.     

川东与大巴山褶皱冲断带交汇区构造几何学和运动学特征

川东与大巴山褶皱冲断带交汇区位于四川盆地东北缘,由温泉井—马槽坝背斜带、云安场背斜带和方斗山背斜带组成,其形成过程受川东构造带和大巴山构造带的双重控制,开展川东与大巴山褶皱冲断带交汇区构造几何学和运动学特征研究,对认识华南板块和华北板块之间的拼贴碰撞及演化具有重要意义。本文基于野外调查、钻测井资料和二维地震资料,以断层相关褶皱理论为指导,通过对四条二维地震剖面的精细解析,揭示了交汇区构造几何学特征,并应用2Dmove软件恢复了研究区构造运动学过程。研究认为:①交汇区在南北方向上显示为大型的复向斜结构,垂向上被区内下三叠统嘉陵江组膏盐层、志留系泥页岩层和下寒武统泥页岩层三套滑脱层分为上、中、下三大构造层,上构造层主要发生滑脱褶皱变形,中、下构造层发育断层较多,主要发育双冲构造、冲起构造以及断层转折褶皱;②研究区中构造层构造变形最为强烈,构造缩短率达10%,上、下构造层构造缩短率较小,均为6%左右,且各构造层缩短率由西到东呈现出逐渐增大的趋势;③中生代以来,研究区的构造演化过程分为三个阶段:晚三叠世到晚侏罗世稳定沉积阶段、早白垩世到古近纪早期对冲变形阶段、古近纪晚期至今定型阶段。     

全金属螺杆钻具研究现状与关键技术

螺杆钻具作为一种容积式动力钻具,具有良好的输出硬特性,是当前应用最广泛的井下动力钻具之一。螺杆钻具的耐温性是其研究的热点所在,可扩大其应用范围和延长工作寿命,在深部高温钻探领域,具有良好的发展前景。本文在阐明螺杆钻具的基本原理和特性基础上,调研分析了常规螺杆钻具的发展现状,重点调研分析了美国全金属螺杆钻具的研发现状与国内全金属螺杆钻具的发展,提出了全金属螺杆钻具的关键技术,为国内开展这项前沿钻具技术的研发提供参考。     

小口径涡轮钻具减速器非对称齿轮弯曲强度分析

小口径涡轮钻具减速器是小井眼深井钻探钻具的重要部件,具有体积小、承载大的特点。采用非对称齿轮代替传统齿轮是提高减速器承载能力的有效手段。非对称齿轮两侧的齿根圆角半径和压力角是区别于对称齿轮的关键参数,通过改变齿轮的齿形结构进而影响了齿轮的齿根弯曲强度。为了进一步研究齿根圆角半径和工作侧压力角对齿根弯曲应力的影响规律,以φ127 mm涡轮钻具减速器中太阳轮为研究对象,建立非对称齿轮的受力模型,基于平截面法得到非对称齿轮齿根弯曲应力的理论计算公式,并通过有限元法对对称齿轮和非对称齿轮进行对比分析,仿真结果表明：增大齿根圆角半径能增大齿轮齿根过渡曲线的曲率半径,从而改善齿根处的应力集中;工作侧压力角的增大能有效降低齿根弯曲应力,但压力角超过一定值时,齿根弯曲应力逐渐趋于稳定。理论分析和仿真结果基本吻合,研究结果可以为优化减速器非对称齿轮的主要参数提供依据和参考。     

高位远程滑坡冲击铲刮效应研究进展及问题

冲击铲刮效应一直是中国西南山区高位岩质滑坡动力学研究的热点问题。文章在开展大量的野外调查基础上,结合目前国内外的研究现状,对目前的基础理论和研究方法进行了归纳总结;从国内外高位远程铲刮型滑坡的典型案例入手,总结了高位远程滑坡的冲击铲刮模式主要有嵌入铲起模式、裹挟刮带模式、冲击滑移模式和冲击飞溅模式;提出了在高位滑坡冲击铲刮研究中的难点和重点问题;并在理论解析、数值计算、人工智能和风险预测方面对今后的冲击铲刮研究思路进行了展望。目的是为冲击铲刮效应响应下的高位滑坡成灾模式和动力学特征分析提供重要的研究基础,为高位远程滑坡动力研究、科学防灾减灾和科学救援工作提供技术支撑。