Rock physics and seismic modeling ofshale reservoirs with horizontal fractures

The presence of horizontal fractures enhances seismic anisotropy of shales. Calculation based on the effective medium theory indicates that horizontal fractures have little effects on velocities along the direction parallel to fractures,but can significantly reduce velocities along the direction normal to fractures. Seismic responses of shales with horizontal fractures are calculated based on the reflector model and the anisotropic propagator matrix method,in which the reflections are a combination of the contrast in impedance due to the variations in fracture density,anisotropic propagation of waves within the shales,and the tuning and interferences associated with layer thickness. Calculated results indicate that seismic reflections are sensitive to reservoir layer thickness and fracture density. Anisotropic propagation alters amplitudes and phases of reflections. It corresponds to higher reflection amplitudes for the case of surrounding sandstone with higher velocity because the increase in fracture density increases the contrast in impedance between the shale and sandstone. In contrast,the surrounding sandstone with lower velocity corresponds to lower reflection amplitudes for the increase in fracture density.

对2013年南京亚青会建邺区生活饮用水的全面检测情况作以分析和探讨

目的为保障2013年8月第二届亚青会在我市顺利召开,对主会场建邺区各大宾馆、饭店及高档小区的饮用水方面进行全面的检测,并对检测结果作以分析和探讨。方法按照《生活饮用水卫生标》(GB/T5750-2006)中的方法采集建邺区1月到7月间的水样306份,保存并运送到实验室进行检测,卫生评价按照《生活饮用水卫生标准》(GB5749-2006)执行。结果 2013年1—7月共检水箱水306份,其中所检项目全部合格的有175份样品,合格率为57.2%,游离余氯合格率较低仅为57.5%。结论本地区水质总体情况较好,但消毒剂使用情况掌握不好导致游离余氯合格率较低,为保障亚青会用水安全,必须加强监测力度。