扬子地台北缘晚震旦世微古植物特征及意义

本文着重研究了扬子地台北缘上震旦统陡山沱组、灯影组及下寒武统下部岩家河段的微古植物组合特征。初步建立了Ⅰ、Ⅱ两个微古植物组合，分别与陡山沱村阶和灯影峡阶相对应，分析了微古植物组合在地层划分与对比及在震旦系－寒武系界线的划分上所起的作用。     

THE HYDROLOGICAL CHARACTERISTICS AND WATER BUDGET OF QINGHAI LAKE DRAINAGE BASIN

The rapid shrinkage of the surface area reflects the long-term deficit water budget of Qinghai Lake. Study of the yearly hydrology and meteorology in the lake catchment basin and the hydrologic factors as well as water budget led to the conclusion that evaporation exceeding the water input resulted in the drop of lake level, thai the obvious decrease of runoff to the lake and precipitation on the catchment accelerated the falling of lake level before 1987. and that increase of about 6.7% in rainfall on the whole basin will balance the lake's water budget.     

The conformity of HI galaxies in ALFALFA-SDSS sample

The conformity effect,indicating the evolution of galaxies is related to its surrounding neighbor galaxies as far as a few Mpc,is an interesting phenomenon in the modeling of galaxy and evolution.Here we study the conformity effect of HI galaxies in a matched galaxy sample between SDSS DR7 and ALFALFA surveys.By checking the probability difference for the detected H i galaxies as a function of distance around a normal or an H i galaxy,we find that this effect is significant out to 5 Mpc.It also shows a dependence on the stellar mass of galaxies,with the strength the strongest in the stellar mass range of 10¹⁰*/M_⊙<10^10.5.However,when the sample is confined to central galaxies in groups with virial radii smaller than 1 Mpc,the 1-halo conformity signal is still evident,while the 2-halo conformity signal is reduced to a very weak amplitude.Our results confirm the previous study in the optical band that the 2-halo term is possibly caused by the bias effect in the sample selection.Furthermore,we confirm the existence of the 1-halo conformity discovered in the optical and radio band in previous investigations.Our results provide another viewpoint on the conformity effect and hope to shed light on the co-evolution of the galaxies and their neighbors in the current galaxy formation models.     

Discovery of Four New Clusters in the Cygnus Cloud

We report the discovery of four new open clusters(named QC 1,QC 2,QC 3 and QC 4)in the direction of Cygnus Cloud and select their members based on five astrometric parameters(l,b,ω,μα*,μδ)of Gaia DR2.We also derive their astrophysical parameters for each new cluster.Structure parameters are generated by fitting the radial density distribution with a King’s profile.Using solar metallicity,we performed isochrone-fitting on their purified color-magnitude diagrams(CMDs)to derive the age of the clusters.The known cluster NGC 7062 in an adjacent area is chosen to verify our identification process.The estimated distance,reddening and age of NGC 7062 are in good agreement with the literature.     

离子刻蚀全息光栅的研究

利用国产的光刻胶和国产离子刻蚀机在蒸镀的铝基衬底上进行刻蚀全息光栅,在国内是一项较新的技术。本文介绍和论述了该试验工作的工艺过程、参数计算和测试方法,得出了试验结果和参数计算值基本吻合的结论,并指出了进一步改善质量的方向。     

Filtering vibroseis data in the precorrelation domain

Vibroseis data recorded at short source–receiver offsets can be swamped by direct waves from the source. The signal-to-noise ratio, where primary reflections are the signal and correlation side lobes are the noise, decreases with time and late reflection events are overwhelmed. This leads to low seismic resolution on the vibroseis correlogram. A new precorrelation filtering approach is proposed to suppress correlation noise. It is the ‘squeeze-filter-unsqueeze’ (SFU) process, a combination of ‘squeeze’ and ‘unsqueeze’ (S and U) transformations, together with the application of either an optimum least-squares filter or a linear recursive notch filter. SFU processing provides excellent direct wave removal if the onset time of the direct wave is known precisely, but when the correlation recognition method used to search for the first arrival fails, the SFU filtering will also fail. If the tapers of the source sweeps are badly distorted, a harmonic distortion will be introduced into the SFU-filtered trace. SFU appears to be more suitable for low-noise vibroseis data, and more effective when we know the sweep tapers exactly. SFU requires uncorrelated data, and is thus cpu intensive, but since it is automatic, it is not labour intensive. With non-linear sweeps, there are two approaches to the S,U transformations in SFU. The first requires the non-linear analytical sweep formula, and the second is to search and pick the zero nodes on the recorded pilot trace and then carry out the S,U transformations directly without requiring the algorithm or formula by which the sweep was generated. The latter method is also valid for vibroseis data with a linear sweep. SFU may be applied to the removal of any undesired signal, as long as the exact onset time of the unwanted signal in the precorrelation domain is known or determinable.     

On the linear elastic responses of the 2D bonded discrete element model

The bonded discrete element model (DEM) is a numerical tool that is becoming widely used when studying fracturing, fragmentation, and failure of solids in various disciplines. However, its abilities to solve elastic problems are usually overlooked. In this work, the main features of the 2D bonded DEM which influence Poisson's ratio and Young's modulus, and accuracy when solving elastic boundary value problems, are investigated. Outputs of numerical simulations using the 2D bonded DEM, the finite element method, a hyper elasticity analysis, and the distinct lattice spring model (DLSM) are compared in the investigation. It is shown that a shear interaction (local) factor and a geometric (global) factor are two essential elements for the 2D bonded DEM to reproduce a full range of Poisson's ratios. It is also found that the 2D bonded DEM might be unable to reproduce the correct displacements for elastic boundary value problems when the represented Poisson's ratio is close to 0.5 or the long-range interaction is considered. In addition, an analytical relationship between the shear stiffness ratio and the Poisson's ratio, derived from a hyper elasticity analysis and applicable to discontinuum-based models, provides good agreement with outputs from the 2D bonded DEM and DLSM. Finally, it is shown that the selection of elastic parameters used the 2D bonded DEM has a significant effect on fracturing and fragment patterns of solids.     

罕见矿物--六方球方解石的发现及特征

大庆油田部分三元复合驱抽油井结垢现象比较严重。井中结垢损害抽油设备，增加了生产成本。通过运用XRD，IR，SEM和化学分析手段对抽油井垢的研究发现，垢的主要化学成分为CaO和SiO2，其含量分别为67％和28％，油井垢中的主要矿物成分是罕见矿物——六方球方解石。六方球方解石呈微晶状(1—10μm)，并常常以微晶聚集的球粒状出现，同时伴生有无定形SiO2。呈游离态的SiO2和有机质对于六方球方解石的形成起到了重要作用。     

山西沁水盆地中,南部现代构造应力场与煤储层物性关系之探讨

山西沁水盆地中、南部下二叠统山西组主煤储层现代构造应力场主应力差增大、煤储层渗透率梯度呈指数形式增长,煤储层压力梯度呈对数增长,这种规律主要受控于现代构造应力场应力方向与煤储层天然裂隙优势发育方向之间的相互关系,这两组方向对于煤储层来说近于平行,对煤储层顶板则表现为近于正交,由此导致主煤储层中天然裂隙处于相对拉张状态,而其顶板天然裂隙处于挤压状态,主应力 越大,相对拉张效应就越显著。基于这种规律和     

共散射点道集与角道集串级优化叠前偏移速度分析

推导了基于角度域共成像点道集的叠前深度偏移层析速度分析公式,提出一种共散射点（CSP）道集与角道集串级优化叠前偏移的速度分析方法。该方法通过基于CSP道集的叠前时间偏移速度分析获取初始速度,利用基于角度域共成像点道集（ADCIGs）的叠前深度偏移速度分析进行速度更新。实现步骤概括为：将叠前地震数据映射为CSP道集,利用CSP道集叠加速度谱拾取能量团获取均方根（RMS）速度场;通过Dix公式将RMS速度转换为层速度作为层析的初始输入速度,基于ADCIGs实现叠前深度偏移层析速度反演,最终得到高精度的叠前偏移速度场。断层模型和实际资料试算结果验证了该方法的正确性和有效性。