Yucatán karst features and the size of Chicxulub crater

The buried Chicxulub impact structure is marked by a dramatic ring of sinkholes (called cenotes if containing water), and adjacent less prominent partial rings, which have been shown to coincide with maxima in horizontal gravity gradients and a topographic depression. These observations, along with the discreteness and spacing of the features, suggest a formation mechanism involving faulting in the outer slump zone of the crater, which would thus have a diameter of approximately 180 km.
An opposing view, based primarily on the interpretation of gravity data, is that (he crater is much larger than the cenote ring implies. Given the association of the known cenote ring with faults, we here examine northern Yucatan for similar rings in gravity, surface features and elevation, which we might expect to be associated with outer concentric faults in the case of a larger, possibly multiring, structure.
No such outer rings have been found, although definite patterns are seen in the distribution of karst features outside the crater rim. We explain these patterns as resulting mainly from deformation related to the block fault zone that parallels tbe shelf edge of eastern Yucatan.     

测氡法快速确定油气田边界及深度

本介绍了运用测氡法快速确定大庆××油气田边界，估算其埋藏深度试验，结果表明，该方法具有可行性和实用性。由于所做工作有限，尚属经验性探讨，还必须从理论和实践上进一步地工作，进而充实、完善它。     

利用相关分析划分重力异常

本文从理论上对相关分析法区分重力异常的可行性进行了论述，并从一元线性回归方程着手，对大地水准面上的重力值与相应的地形高程作了相关分析，通过分析，认为在区域性小比例主均衡补偿基本完善的条件下，重力值与高程有极好的线性相关关系；当计算窗口较大时，地下的局部不均匀体，不足以破坏重力值与高程的相头发一，所以，在实际工作中，利用相关分析处理重力资料的叠加场，可以收到较好的效果，且方法简单易行。     

Comparison of the pseudo-static and dynamic behaviour of gravity retaining walls

Summary Pseudo-static and dynamic non-linear finite element analyses have been performed to assess the dynamic behaviour of gravity retaining walls subjected to horizontal earthquake loading. In the pseudo-static analysis, the peak ground acceleration is converted into a pseudo-static inertia force and applied as a horizontal incremental gravity load. In the dynamic analysis, an actual measured earthquake acceleration time history has been scaled to provide peak ground acceleration values of 0.1 g and 0.3 g. Good agreement is obtained between the pseudo-static analysis and analytical methods for the calculation of the active coefficient of earth pressure. However, the results from the dynamic analysis require careful interpretation. In the pseudo-static analysis, the increase in the point of application of the resultant active force with the horizontal earthquake coefficient k _h from the one-third point to the mid-height of the wall is clearly observed. In the dynamic analysis, the variation in the point of application is shown to be a function of the type of wall deformation. Both finite element analyses indicate the importance of determining the magnitude of the predicted displacements when assessing the behaviour of the wall to seismic loading.     

应用砼的流变性计算砼的灌注参数

应用流体力学、流变学的理论，方法和施工实测数据，建立水下灌注理导管埋深，砼在灌注系统的流动阻力与导管内附加砼柱间的数学表达式，以指导水下灌注施工在最优灌注参数下进行。     

ADVANCES IN MEASURING TECHNIQUES OF BED LOAD

I.m~UCrIONBedloadisthesedimentwhichmovesalongtheriverbedintheformofrolling,slidingandsaltation.BedloadmaycreatemanyproblemsintheoperationandmaintenanceofnavigationchannelandinthedevelOPmentofhydroelectricity.Dataofbedloaddischargearealsorequiredinthedesignofreservoir,inwhichtheinflowbedloadareallactuallytrapped.Thewaysofbedloadmotionaredifferentfordifferentsizes.Thus,itisextremelydifficulttodeterminethebedloaddischargeaccurately.Manyequationshavebeenproposedtocalculatethebedloaddischarge.H…     

The law of dislocation between two sides of active faults in China and their geodynamic force

By contrasting and analyzing the characteristics of gravity field nearby some important active faults in the continent of China, it can be found that the crust blocks where Bouguer anomalies are regionally positive (or relatively positive) are moving towards the terrestrial poles and the blocks where Bouguer anomalies in a tremendous area are negative (or relatively negative) are moving towards the equator. By analysis of mechanics and mathematics calculation and based on lots of practical data, the authors hold that the change in density of a crust block is a decisive factor that causes the horizontal movement of the continental crust, while magma activity is an important factor that leads to the change in density of a crust block.     

塔里木盆地卫星重力异常与油气资源的相关性研究

利用中国地区３６０阶局部重力场模型ＩＧＧ９３Ｅ，计算出不同阶窗的卫星重力异常，然后利用Ｍｏｌｏｄｅｎｓｋｙ单层密度积分方程将卫星重力转化为分层面密度异常，结合其他地球物理资料，分析并探讨了塔里木盆地油气资源与卫星重力异常的相关性。研究表明：塔里木盆地油气资源分布与１０１－１８０阶卫星分同密度异常图中负密度异常带关系密切。而１８１－３６０阶卫重分层面异常图则对盆地内生油、储油的坳陷、隆起等构造有较９     

长江三峡狮子口重力滑动构造

围绕着长江三峡库处区狮子口ＮＮＷ向线性影像带的构造性及其地壳稳定性评价问题进行了专题研究，以区域地质调查为基础，运用构造解析方法，采用多学科，多手段的综合研究，确认该影像带影像特征最明显的地段乃是一个滑褶型多层式得力滑动构造，本文还分析了该系统形成的介质条件，斜坡构造及动力环境。