准噶尔盆地吉木萨尔凹陷二叠系芦草沟组储层介—宏孔孔隙结构特征及控制因素

吉木萨尔芦草沟组页岩油资源潜力巨大,为探究其储层介—宏孔孔隙结构特征及控制因素,以研究区芦草沟组钻井岩心为对象,利用X射线衍射、铸体薄片、扫描电镜、孔渗测试、高压压汞、氮气吸附、分形理论、相关性分析等方法,对其储层特征、孔隙结构及控制因素进行了讨论。研究发现：1）研究区芦草沟组储层是一套以长英质碳酸盐岩（A岩）、长英质黏土岩（B岩）、灰/云质细粒长英沉积岩（C岩）、混积岩（D岩）为主的低孔—特低孔、特低渗储层,主要孔隙类型为溶孔,此外还发育有剩余粒间孔、晶间孔、微裂缝;2）研究区芦草沟组储层孔隙分布复杂,孔径分布曲线呈现多峰形,介孔提供了大部分孔容和比表面积;高压压汞计算的宏孔分形维数均值和氮气吸附计算的介孔分形维数均值分别为：2.864 7、2.507 5,介孔孔隙结构复杂程度相对较低;3）有机质丰度有利于A岩、B岩和C岩宏孔孔隙结构的发育,会导致C岩介孔和D岩孔容、比表面积减小;有机质演化程度对A岩介孔、B岩和C岩介孔起到建设作用,对C岩宏孔、D岩介—宏孔有破坏做用;4）脆性矿物含量越高C岩介孔和D岩孔容比表面积越大,而A岩、B岩宏孔、C岩宏孔孔容、比表面积减小;黏土矿物对A岩介孔、C岩介孔及D岩的孔隙系统发育起到建设作用,对B岩宏孔和C岩宏孔有破坏作用。孔隙结构的发育主要受有机质（有机质丰度、有机质演化程度）和矿物组份（脆性矿物含量、黏土矿物含量）的影响,不同岩性、不同尺度的孔隙发育影响因素各有差异。

     

Rock salt mass in the Paleoproterozoic sequence of the Onega trough in Karelia (from the Onega parametric well data)

A thick (200 m) rock salt mass covering Late Archean granitoids was exposed for the first time in the Early Proterozoic volcanogenic-sedimentary formations in the Onega trough of the east Baltic Shield by the Onega parametric well. The mineral composition of salts, their geochemical features, and the isotopic composition of carbonate carbon and oxygen have been studied. After fluid inclusions present in salts, their metamorphism temperature and isotopic composition of helium and argon were determined. The obtained results give evidence of the fact that rock salts and magnesites associated with them were formed in an evaporate basin with participation of deep crustal processes. The age of the underlying granitoids (2.716 ± 9 Ma) is determined using the Pb—Pb method.     

快速城市化区域耕地变化与经济发展关系研究——以重庆市九龙坡区为例

以重庆市九龙坡区为例,分析了快速城市化区域耕地面积变化与经济发展之间的动态变化特征,并运用脱钩理论深入研究了耕地面积变化与经济发展之间的脱钩情况。结果表明：（1）随着人均GDP的直线增长,九龙坡区的耕地面积不断减少。（2）固定资产投资增长率与耕地面积减少率之间存在一定的同步性,而GDP增长率滞后于耕地面积减少率。（3）九龙坡区耕地面积变化和经济发展之间有类似的库兹涅茨曲线特征,但受耕地面积的自身波动变化影响,库兹涅茨曲线特征不是十分典型。（4）脱钩分析表明九龙坡区以绝对脱钩占主导地位,脱钩指数在波动变化中呈减小趋势。     

The Karoo Basin of South Africa: type basin for the coal-bearing deposits of southern Africa

The coal-bearing sediments and coal seams of the Karoo Basin, Southern Africa are described and discussed. The Karoo Basin is bounded on its southern margin by the Cape Fold Belt, onlaps onto the Kaapvaal Craton in the north and is classified as a foreland basin. Coal seams are present within the Early Permian Vryheid Formation and the Triassic Molteno Formation.The peats of the Vryheid Formation accumulated within swamps in a cool temperate climatic regime. Lower and upper delta plain, back-barrier and fluvial environments were associated with peat formation. Thick, laterally extensive coal seams have preferentially accumulated in fluvial environments. The coals are in general inertinite-rich and high in ash. However, increasing vitrinite and decreasing ash contents within seams occur from west to east across the coalfields. The Triassic Molteno coal seams accumulated with aerially restricted swamps in fluvial environments. These Molteno coals are thin, laterally impersistent, vitrinite-rich and shaly, and formed under a warm temperate climatic regime.Palaeoclimate, depositional systems, differential subsidence and basin tectonics influence to varying degrees, the maceral content, thickness and lateral extent of coal seams. However, the geographic position of peat-forming swamps within a foreland basin, coupled with basin tectonics and differential subsidence are envisaged as the primary controls on coal parameters. The Permian coals are situated in proximal positions on the passive margin of the foreland basin. Here, subsidence was limited which enhanced oxidation of organic matter and hence the formation of inertinitic coals. The coals in this tectonic setting are thick and laterally extensive. The Triassci coals are situated within the tectonically active foreland basin margin. Rapid subsidence and sedimentation rates occurred during peat formation which resulted in the preservation of thin, laterally impersistent, high ash, vitrinite-rich, shaly coals.     

Fluid-pressure variations and fault creep in central California

Observations of the change of water level in wells near the San Andreas fault in centra California indicate that there are pore-pressure changes associated with the process of fault creep. The sense of water-level and pore-pressure changes may indicate the direction of creep propagation.     

Investigation of insulation layer dynamic characteristics for high-speed railway

Dynamic performance of insulation is one of the key parameters during the insulation application for high-speed railway subgrade. This paper conducted laboratory and field tests for the materials and dynamic load,especially for thermal performance, elastic deformation, and accumulated deformation of insulation materials.Experiment results show that mechanical properties of insulation layer structure are stable, which satisfies the requirements of the high speed railway.     

土壤水盐运移模型研究进展及展望

回顾了国内外土壤水盐运移模型的发展历程,根据土壤水盐运移模型构成的原理和发展趋势,将土壤水盐运移模型分为水盐平衡模型、物理模型和系统模型。借助国内外文献对已有模型的原理和应用进行了介绍,并对存在的问题进行了分析;展望了新形势下土壤水盐运移模型的未来发展趋势和研究重点,旨在为今后土壤水盐运移模型研究提供新的思路。