基于Shearlet变换和广义全变分正则化的地震数据重建

压缩感知技术通常利用地震信号在某一变换域内的稀疏性质,将随机缺失的地震数据重建问题转化为L1正则化问题.本文首先通过Shearlet变换获得地震信号的稀疏性质,再将广义全变分（TGV）约束引入L1正则化模型,构建了基于Shearlet变换的双正则化模型用于重建地下介质的图像.与传统L1正则化方法相比,基于Shearlet变换的双正则化方法不仅考虑了信号的稀疏性,同时兼顾了地下介质结构的复杂性,可以较好的重建地下结构体的图像.最后采用交替方向乘子法（ADMM）求解所建模型,每个子问题均可得到显式解.数值实验对比了基于小波变换、Shearlet变换的L1正则化方法和TGV正则化方法,结果表明基于Shearlet变换的双正则化方法对于随机采样50%数据的情况具有较好的重建结果,同时对于有限范围的连续缺失数据的重建亦具有一定的有效性.     

一个典型的含煤湿地扇

本文依据野外实际资料,参考了近年来国内、外有关湿地扇的文献,研究了义马煤田义马组下部砾岩段岩性、岩相、沉积构造、古流向、砾岩体展布状态等沉积特征,认为该段是一个典型的含煤复合湿地扇沉积。并进一步划分出了扁根、扇中、扇缘和扇间等亚相。最后还探讨了其聚煤特征。     

Experimental Study on Ocean Internal Wave Force on Vertical Cylinders in Different Depths

A series of experimental studies about the force of internal solitary wave and internal periodic wave on vertical cylinders have been carried out in a two-dimensional layered internal wave flume. The internal solitary waves are produced by means of gravitational collapse at the layer thickness ratio of 0.2, and the internal periodic waves are produced with rocker-flap wave maker at the layer thickness ratio of 0.93. The wave parameters are obtained through dyeing photography. The vertical cylinders of the same size are arranged in different depths. The horizontal force on each cylinder is measured and the vertical distribution rules are researched. The internal wave heights are changed to study the impact of wave heights on the force. The results show that the horizontal force of concave type internal solitary wave on vertical cylinder in the upper-layer fluid has the same direction as the wave propagating, while it has an opposite direction in the lower-layer. The horizontal force is not evenly distributed in the lower fluid. And the force at different depths increases along with wave height. Internal solitary wave can produce an impact load on the entire pile. The horizontal force of internal periodic waves on the vertical cylinders is periodically changed at the frequency of waves. The direction of the force is opposite in the upper and lower layers, and the value is close. In the upper layer except the depth close to the interface, the force is evenly distributed; but it tends to decrease with the deeper depth in the lower layer. A periodic shear load can be produced on the entire pile by internal periodic waves, and it may cause fatigue damage to structures.     

喇嘛甸油田北块萨零组储层沉积微相

喇嘛甸油田位于大庆长垣的最北端,是受构造控制的不对称的短轴背斜气顶油藏,萨零组位于萨尔图油层的顶部,属于下白垩统的嫩一段.根据取心井岩心描述、粒度分析、测井曲线特征,结合喇嘛甸油田沉积背景,对萨零组北块储层的沉积微相进行精细划分,进一步划分为水下分流河道、席状砂、表外储层微相,认为主要储层砂体为水下分流河道砂和席状砂.详细分析了沉积微相的平面展布特征,绘制沉积相带图.揭示了喇嘛甸油田的构造特征、沉积环境特征,确定了萨零组为三角洲外前缘沉积,为指导萨零组油气层的开发提供精细地质描述.     

义马煤田煤厚变化律规

义马煤田早、中侏罗世含煤岩系属于内陆山间盆地型沉积。煤田内出露地层有上三叠统、侏罗系、白垩系、第三系及第四系。其中侏罗系中、下统义马组为主要含煤岩系,共含煤六层,其中以2—3煤层厚度最大,全区普遍可采。2—1煤层为2—3煤层的一个分叉,区内大面积分布,普遍可采。其它煤层局部地段发育,局部可采。本文讨论煤厚变化规律及其原因,即指2—3煤层及2—1煤层而言。      

非均匀各向同性介质中弹性波传播的盒式积分法模拟

为方便积分差值法的精确处理,利用积分差值法,将运动方程、自由边界条件及人工边界上的吸收边界条件进行积分,根据高斯定理得出了二维非均匀介质中弹性波传播的二阶显式差分格式。并针对几个典型的地质模型,计算了其弹性波传播的数值模拟结果,结果表明,该方法有较好的精度和稳定性。