Numerical simulation of three-dimensional saltwater–freshwater fingering instabilities observed in a porous medium

We consider saltwater–freshwater fingering instabilities in a saturated porous medium. In the first part, we present three-dimensional results obtained from a laboratory experiment using non-invasive imaging. In the second part, we define a set of model problems in which the performed laboratory experiments can be ranged in. Due to its highly non-linear behavior and inevitable modeling errors, a detailed numerical reproduction of the physical concentration measurements cannot be expected. Nevertheless, four criteria have been identified, two quantitative and two qualitative, which facilitate a substantiated comparison of the physical experiment and the numerical simulation. With respect to these criteria a high degree of similarity could be observed. The use of these features allows a deeper understanding of the physical processes and the influence of the initial conditions.     

无人机载线阵摆扫CCD影像几何校正

充分利用无人机载GPS/INS组合导航系统提供的导航遥测数据,首先分析线阵CCD传感器摆扫成像的基础原理和成像特点,并建立严格的成像模型;然后提出线阵摆扫CCD影像严格几何校正的详细算法和流程;最后进行多组实验证实成像模型和几何校正算法的正确性和准确性。实验结果证实采用文中的成像模型和几何校正流程,可获得正确、高精度地理编码的线阵摆扫CCD正射影像。     

用成像测井资料描述碳酸盐岩储集层——以车古20潜山为例

碳酸盐岩、火成岩等复杂性油气藏具有岩性、孔隙空间结构复杂、非均质性强等特点,单纯用常规测井技术很难对这些油气藏进行准确评价,必须借助于成像测井等新技术资料。成像测井不仅能直观地显示各种裂缝、溶洞等地质特征,而且还能定量计算裂缝的各种参数,以及研究孔隙结构。这里详细介绍了成像测井新技术裂缝识别、储层划分、裂缝参数计算、孔洞频谱分析等方法,并利用这些方法描述了车古20潜山碳酸盐岩储集层的裂缝,以及溶蚀孔洞发育特征,识别出了此潜山的储层,还结合其它资料,得出了该潜山油气藏的储层分布规律。     

保持浅层地震反射信息处理方法的研究

在处理泌阳凹陷北部斜坡外带复杂地震资料的过程中,针对浅层地震资料的特点,在消化吸收以往经验的基础上,研制出一套较为完善的、能适应该地区资料特点的浅层处理技术。该套处理技术主要包括叠前去噪技术、静校正技术、地表一致性处理技术、浅层偏移成像技术。实际地震资料的处理结果表明,应用这种技术能够取得较好的处理效果。     

井中声波方法研究的回顾与展望

回顾了井中声波方法二十五年的成长历程和重要成果。展望了井中声波法在金属矿、油气勘探和开发领域的广阔应用前景。提出了未来井中声波方法发展方向的建议。     

低剂量CT心脏成像

采用CT进行心脏成像是CT临床应用中最前沿的进展,心脏扫描中采用较低的螺距使得病人的辐照剂量较高,我们提出一种不同的数据采集和图像重建技术,使病人的辐照剂量减少了50%～89%.该方法的使能技术是64排CT的大容积覆盖范围(40㎜),相对于心脏的平均尺寸是120～140㎜,新的容积CT在3～4步就能够覆盖整个器官.伴随新的数据采集方式,我们也提出了对应的重建算法,克服了不完全投影采样的问题,还进行了广泛的模体和临床实验来阐明所提出方法的有效性.     

Studying surface structure in desert areas using multiple kinds of surface wave data

Shallow surface wave methods are mostly used for investigation of the surface velocity structure in environmental and engineering geophysics in non-desert areas. For the special geological features of the Takelamagan Desert area, we use the multi-channel analysis of surface wave （MASW） method to process multi-channel shallow surface wave records to determine the near surface velocity structure in the desert area. We also process, analyze, and compare the surface waves in many-trace records extracted from the oil exploration shot gathers in the area. We show that the MASW method can determine detailed shallow velocity structure in desert areas and the many-trace records can be used to get detailed deep geological structure. The combination of the two different datasets can obtain the exact velocity structure upper 60 m depth in the survey area.