低渗透性多孔介质渗透性能测定评述

本文简要回顾了用于测定低渗透性多孔介质渗透性能的若干方法，着重对影响低渗透性介质渗透性能测定的有关因素进行了分析，指出对于低渗透性介质，目前还未有标准公认的渗透性能测定方法，尚需做大量的实验与理论研究工作。     

陕北黄土地层地貌特征及工程特性综述

陕北地区作为我国能源基地、农牧业生产基地和旅游基地,工程活动正在不断加强,但对于陕北黄土地区的区域工程特性研究较少。因此,结合野外调研以及相关勘察资料,对陕北黄土地层地貌及工程特性进行了综合分析。研究结果表明: 陕北黄土地层可划分为全新统风积沙、上更新统黄土、中更新统黄土、新近系岩石和古近系岩石; 陕北黄土地貌可划分为黄土侵蚀-构造堆积地貌、黄土现代构造(变形)地貌、黄土湿陷地貌和黄土侵蚀地貌; 因沉积年代和赋存环境的不同,陕北南部和北部黄土的工程特性(主要包括湿陷性、渗透性以及力学性质)迥异。陕北黄土地层地貌特征及工程特性的研究不仅与陕北地区的工程地质、水文地质和环境地质等研究有着密切的联系,而且对于陕北黄土分布区的生态、经济以及国防等国计民生建设具有重要的指导意义。     

利用斯通利波评价复杂岩性储层渗透性

针对海拉尔盆地贝尔凹陷区复杂岩性储层,进行了利用斯通利波估算储层渗透率的应用研究,并把斯通利波渗透率与岩心渗透率和核磁处理渗透率进行了对比。对比结果表明,可依据获得的斯通利波渗透率曲线进行储层的有效性划分。     

滇东—黔西地区晚二叠世煤层割理研究及其在煤层气勘探中的意义

介绍了割理识别准则、面割理和端割理的区分及严格定义、割理级别、割理的研究内容、割理的形成以及割理对煤层渗透性的控制作用。对滇东－黔西地区晚二叠世煤层数个向斜井下二十五块煤样,经制煤片,运用定性、定量分析和显微镜下观测相结合的方法,对煤裂隙（割理）进行系统的研究和比较,得出结论：数个向斜中,盘关向斜和格目底向斜煤样煤层裂隙（割理）普遍发育良好。     

广州饱和软土固结过程微孔隙变化的试验分析

软土的孔隙特征及其变化规律对软土的压缩性和渗透性有重大的影响,软土孔隙特征随荷载变化规律的试验研究为揭示软土排水固结过程与变形规律,建立基于孔隙压缩规律和渗流机制的排水固结模型提供有力依据。利用美国全自动压汞仪,对不同压力下固结的广州番禺淤泥土样的孔隙及其尺度分布进行测试,根据测试结果对土样孔隙尺度分布特征及其随固结压力的变化规律给出了定量分析。试验结果表明：淤泥土中介于0.4～2.5 μm范围的颗粒间及团粒内的小孔隙所占比例最大,而大于10 μm的大孔隙和小于30 nm的超微孔隙所占比例均很小;较大的孔隙更易于被压缩而湮灭或被分裂成微小孔隙;固结压力将显著改变淤泥土的孔隙尺度及其分布特征,以致改变土体的压缩性和渗透性。在固结前期( 200 kPa)孔隙尺度较大,压缩系数和渗透系数较大并随固结压力增加而快速减小;在固结后期( 200 kPa)孔隙尺度小,压缩系数和渗透系数小,且随固结压力增加的变化趋于平缓。     

Seismic Signatures of Rock Pore Structure

Rock pore structure is one of the important parameters in controlling both seismic wave velocity and permeability in sandstones and carbonate rocks. For a given porosity of two similar rocks with different pore structures, their acoustic wave speeds can differ 2 km/s, and permeability can span nearly six orders of magnitude from 0.01 mD to 20 D in both sandstone and limestone. In this paper, we summarize a two-parameter elastic velocity model reduced from a general poroelastic theory, to characterize the effect of pore structures on seismic wave propagation. For a given mineralogy and fluid type of a reservoir, this velocity model is defined by porosity and a frame flexibility factor, which can be used in seismic inversion and reservoir characterization to improve estimation of porosity and reserves. The frame flexibility factor can be used for quantitative classification of rock pore structure types (PST) and may be related to pore connectivity and permeability, using both poststack and prestack seismic data. This study also helps explain why amplitude versus offset analysis (AVO) in some cases fails for the purpose of fluid detection: pore structure effect on seismic waves can mask all the fluid effects, especially in carbonate rocks.     

全吸力范围非饱和持水函数和渗透性函数的预测模型

非饱和土的持水函数和渗透性函数是刻画其持水能力和水分运移的基本参数。由于物理机制不同,持水函数及渗透性函数在毛细阶段和吸附阶段的特征有显著差异。多数传统的持水和渗透性函数仅考虑了毛细阶段内,毛细水的持水和渗透特性,不能表征吸附阶段内吸附水的特征。为使传统函数模型在吸附阶段也适用,以传统VG持水函数和VG-M渗透性函数为基础,用修正参数C(ψ)修正VG持水函数,并以此确定非饱和土的残余值ψ_r,区分毛细水的毛细流动和吸附水的薄膜流动。基于薄膜流动的特点,提出参数Γ(ψ),改进了传统VG-M渗透性函数在吸附阶段内低估非饱和渗透系数这一问题,从而建立了全吸力范围的渗透性函数模型。最后用3组持水及渗透性试验结果验证修正模型的合理性,结果表明修正持水函数模型和渗透性函数模型的预测结果在吸附阶段较传统模型更符合实测结果。     

采动影响下煤层覆岩渗透性变化规律及垂向分带特征

以孟加拉国Barapukuria煤矿X工作面为试验区,采用井下钻孔分段压水原位测试及相关理论计算方法,研究了工作面回采前后覆岩渗透性变化规律及垂向分带特征。研究结果表明,工作面回采前后,覆岩渗透性变化显著,采后覆岩渗透性具有明显的垂向分带特征。自覆岩导水裂缝带顶部至底部,渗透性呈阶梯状逐渐增大,可细分为弱渗透带、中渗透带和强渗透带。研究结果对煤矿区水文地质参数识别与涌水量预测工作具有指导意义。     

渗透性反应墙（PRB）对地下水石油污染修复技术研究

PRB技术作为一种新兴的地下水污染原位修复技术,与其他地下水污染的修复技术相比,主要优点是对污染物具有良好的去除效果,且不需要对地下水进行抽泵和回灌;PRB系统中的反应介质消耗很慢,有几年甚至几十年的处理能力,且除了须长期监测外几乎不需要运行费用。     

2D-Cell Experiment on Methyl Tert-Butyl Ether Transport in Saturated Zone of Groundwater

As an additive of gasoline,methyl tert-butyl ether(MTBE)has a higher solubility in water,which is about 20 times as high as that of benzene.This characteristic results in MTBE dissolving out of the gasoline into the soil and groundwater.Due to relative unique physicochemical behavior of MTBE it would be an ideal candidate for use in environmental forensic investigations.In order to study the transport and distribution of MTBE in saturated zone of ground water,a two-dimensional experimental cell was setup to simulate the real environment of the groundwater flow.The effects of soil and groundwater flow velocity on the MTBE transport were investigated.The results show that the mobile distance of MTBE in vertical direction was smaller than that in horizontal direction paralleling with the groundwater flow.Because the main dynamics of groundwater flow direction was convection and dispersion,the movement of MTBE is also diffusion in the vertical direction.In addition,the transport of MTBE was more quick in high permeability porous media,and the increase of groundwater flow velocity can accelerate the MTBE plume de-velopment,but the irregularity and randomness of the plume are enhanced synchronously.These research results can give some helps for the investigation of MTBE movement in the groundwater,also can make some references for other petroleum contamination behavior.