A Note on the Effect of Negative Poisson’s Ratio on the Deformation of a Poroelastic Half-Space by Surface Loads

The aim of this note is to study the effect of negative Poisson’s ratio on the quasi-static deformation of a poroelastic half-space with anisotropic permeability and compressible fluid and solid constituents by surface loads. Two particular cases considered are: two-dimensional normal strip loading and axisymmetric normal disc loading. It is found that a negative Poisson’s ratio makes the Mandel-Cryer effect more prominent. It also results in an increase in the magnitude of the surface settlement.

Earth Pressure Distribution and Sand Deformation Around Modified Suction Caissons(MSCs) Under Monotonic Lateral Loading

The modified suction caisson(MSC) is a novel type of foundation for ocean engineering, consisting of a short external closed-top cylinder-shaped structure surrounding the upper part of the regular suction caisson(RSC). The MSC can provide larger lateral bearing capacity and limit the deflection compared with the RSC. Therefore, the MSC can be much more appropriate to use as an offshore wind turbine foundation. Model tests on the MSC in saturated sand subjected to monotonic lateral loading were carried out to investigate the effects of external structure sizes on the sand surface deformation and the earth pressure distribution along the embedded depth. Test results show that the deformation range of the sand surface increases with the increasing width and length of the external structure. The magnitude of sand upheaval around the MSC is smaller than that of the RSC and the sand upheaval value around the MSC in the loading direction decreases with the increasing external structure dimensions. The net earth pressure in the loading direction acting on the internal compartment of the MSC is smaller than that of the RSC at the same embedded depth. The maximum net earth pressure acting on the external structure outer wall in the loading direction is larger than that of the internal compartment, indicating that a considerable amount of the lateral load and moment is resisted by the external skirt structure.

Relationships between Earth’s Rotation or Revolution and Geographical Extent of the Global Surface Monsoons

Monsoon seasons, occasionally also known as wet seasons or trade-wind littoral seasons, are found in the regions where there is a complete seasonal reversal of the prevailing surface winds. Accompanying these shifts in the prevailing surface winds are modulations in rainfall activity. Given the fact that our knowledge of the monsoons is mainly based on the interpretation of the mean values of precipitation, cloudiness and winds;relationships between earth’s rotation or revolution and geographical extent of the global surface monsoons deserve to be highlighted. In the abundant literary and audiovisual production devoted to monsoons worldwide and despite the fact that everyone agrees with physical law which shows that Coriolis force acts to the right in the northern hemisphere (to the left in the southern hemisphere), there is no reference to the relationship between Coriolis force (due to earth’s rotation) effects on troposphere general circulation and geographical extent of the global surface monsoons. Furthermore knowing that the ITCZ oscillations on either side of the equators (due to earth’s revolution) determine the seasons (mainly winter and summer), it is clear that earth’s revolution also plays a crucial role in the seasonal reversal of the prevailing surface winds observed in the regions where monsoons are found. Our main objective is to provide a rational answer to the question: what is a monsoon?

Earth’s Atmosphere Prevailing Surface Winds Based on Effectiveness of Mbane Biouele Formula Derived in 2009

Any system designed to simulate the earth's atmosphere general circulation, must necessarily be based on the spatial-or temporal average conditions. Irregularities in the profiles of air motions that we observe on daily weather maps often make lose any real meaning to the general circulation. As complicated and inconsistent that is the daily traffic of air particles, it is interesting to define a general circulation characteristic of the average air transportation around the globe. Indeed, this transport responds to a need to transfer heat from the equator (heat source) to the poles (cold sources). Mbane Biouele formula (2009), derived from Clausius-Clapeyron relation (1832), now allows faithful and unique representation of the tricellular general circulation: Hence, the possibility of access to the earth’s atmosphere prevailing surface winds in summer as well as winter.

Identification and Interpretation of Earth’s Atmosphere Dynamics’ and Thermodynamics’ Similarities between Rogue Waves and Oceans’ Surface Geostrophic Wind

In their daily practices, meteorologists make extensive use of the geostrophic wind properties to explain many weather phenomena such as the meaning and direction of the horizontal winds that take place around the low atmospheric pressures. The biggest challenge that faces the public who is interested in information disseminated by meteorologists is to know exactly what means the geostrophic wind. Besides the literal definitions scattered in very little scientific work, there is unfortunately no book which gives importance to the algebraic definition of the geostrophic wind. Our work shows that to better understand the behavior of natural phenomena, it is essential to combine the theories with based observations. Obviously, observations cannot be relevant without a theory that guides the observers. Conversely, no theory can be validated without experimental verification. Synoptic observations show that in the “free atmosphere!” the wind vectors are very nearly parallel to isobars, and the flow is perpendicular to the horizontal pressure gradient force, at least at any given instant. This kind of information recommends great caution when making geostrophic approximations. Our work also shows that for tornadoes, there is no need to move away from the surface of the oceans to observe the geostrophic balance. Undoubtedly, identification and interpretation of earth’s atmosphere dynamics’ and thermodynamics’ similarities between rogue waves and oceans’ surface geostrophic wind will be an easy exercise to researchers who will give importance to result provided by this paper.

中强地震发震构造标志浅析——以2023年积石山M_(S)6.2地震为例

地震地表破裂是地震发生的重要特征,是研究地震动力学、构造变形的重要手段。一般认为,M6 3/4以上的地震才会形成地表破裂。但近年来,也有M6.0左右的地震发生了地表破裂。本文旨在探讨中强地震地表破裂的识别方法。中强地震发震构造的识别具有一定的挑战性,主要表现在以下几个方面:(1)中强地震地表破裂的规模(位错量、宽度、长度和深度)较小,容易被黄土层厚覆盖,掩盖地表破裂的痕迹,不易识别;(2)非构造成因裂缝干扰,使得难以区分构造成因地表破裂。本文以2023年积石山M_(S)6.2地震为例,对中强地震构造成因破裂的识别标志进行了初步分析,提出了以下识别标志:(1)地表破裂几何展布和剖面形态,地震伴生的次生灾害(滑坡、崩塌、砂土液化等)的线性分布为识别发震构造提供参考和线索;(2)地表破裂沿破裂走向呈现稳定地穿越不同地貌单元,至少穿越一条沟谷等低凹地貌;(3)地表破裂在地质剖面上表现出稳定的产状;(4)地表破裂伴生构造形态,地表沿破裂发育雁列式褶皱(挤压鼓包)与张裂缝交替出现的现象。本文提出的识别标志为中强地震发震构造的识别提供了新的思路。

Discovering Crustal Deformation Bands by Processing Regional Gravity Field

Objectives： This article presents a new computational procedure to discover scratches buried in the earth＇s crust. We also validate this new interdisciplinary analysis method with regional gravity data located in a well-known Dabie orogenic zone for test. Methods： Based on the scratch analysis method evolved with mathematical morphology of surfaces, we present a procedure that extracts information of the crustal scratches from regional gravity data. Because the crustal scratches are positively and highly correlated to crustal deformation bands, it can be used for delineation of the crustal deformation belts. The scratches can be quantitatively characterized by calculation of the ridge coefficient function, whose high value traces delineate the deformation bands hidden in the regional gravity field. In addition, because the degree of crustal deformation is an important indicator of tectonic unit divisions, so the crust can be further divided according to the degree of crustal deformation into some tectonic units by using the ridge coefficient data, providing an objective base map for earth scientists to build tectonic models with quantitative evidence. Results： After the ridge coefficients are calculated, we can further enhance the boundary of high ridge-coefficient blocks, resulting in the so-called ridge-edge coefficient function. The high-value ridge-edge coefficients are well correlated with the edge faults of tectonic units underlay, providing accurate positioning of the base map for compilation of regional tectonic maps. In order to validate this new interdisciplinary analysis method, we select the Dabie orogenic zone as a pilot area for test, where rock outcrops are well exposed on the surface and detailed geological and geophysical surveys have been carried out. Tests show that the deformation bands and the tectonic units, which are conformed by tectonic scientists based on surface observations, are clearly displayed on the ridge and ridge-edge coefficient images obtained in this article. Moreover, these computer-generated images provide more accurate locations and geometric details. Conclusions： This work demonstrates that application of modern mathematical tools can promote the quantitative degree in research of modern geosciences, helping to open a door to develop a new branch of mathematical tectonics.

An Improved Coupled Level Set and Continuous Moment-of-Fluid Method for Simulating Multiphase Flows with Phase Change

An improved algorithm for computing multiphase flows is presented in which the multimaterial Moment-of-Fluid(MOF)algorithm for multiphase flows,initially described by Li et al.(2015),is enhanced addressing existing MOF difficulties in computing solutions to problems in which surface tension forces are crucial for understanding salient flow mechanisms.The Continuous MOF(CMOF)method is motivated in this article.The CMOF reconstruction method inherently removes the"checkerboard instability"that persists when using the MOF method on surface tension driven multiphase(multimaterial)flows.The CMOF reconstruction algorithm is accelerated by coupling the CMOF method to the level set method and coupling the CMOF method to a decision tree machine learning(ML)algorithm.Multiphase flow examples are shown in the two-dimensional(2D),three-dimensional(3D)axisymmetric"RZ",and 3D coordinate systems.Examples include two material and three material multiphase flows:bubble formation,the impingement of a liquid jet on a gas bubble in a cryogenic fuel tank,freezing,and liquid lens dynamics.

S形空间曲线顶管开挖引起的地表沉降计算——以宁波市潘桥变电站迁建工程为例

为研究S形空间曲线顶管隧道施工引起的地表沉降规律,基于Mindlin弹性力学解和随机介质理论,构建S形空间曲线顶管施工引起的地表沉降计算模型,获得顶管施工各参数和空间曲线段施工地层损失引起的沉降规律,并与宁波市潘桥变电站顶管隧道工程地表沉降实测值进行对比验证。研究结果表明:1)考虑顶管施工引起的附加荷载、水平与竖向超挖间隙等因素所构建的S形空间曲线顶管施工引起的地表沉降计算方法,理论计算值与实测值吻合较好,能够对地表沉降进行较为准确的预测;2)空间曲线顶管施工引起的地表沉降槽不以顶管中心轴线对称,在顶管机头无超挖刀参与掘进的情况下,最大沉降值向弯道外侧偏移,且顶管机平面转弯产生的超挖间隙对沉降槽偏移影响最大;3)在S形空间曲线顶进时,地层损失是造成地表沉降的主要原因,应严格控制注浆参数,理论注浆量应包括环形空隙与超挖间隙注浆量体积之和。

Evidences of the expanding Earth from space-geodetic data over solid land and sea level rise in recent two decades

According to the space-geodetic data recorded at globally distributed stations over solid land spanning a period of more than 20-years under the International Terrestrial Reference Frame 2008,our previous estimate of the average-weighted vertical variation of the Earth＇s solid surface suggests that the Earth＇s solid part is expanding at a rate of 0.24 ± 0.05 mm/a in recent two decades.In another aspect,the satellite altimetry observations spanning recent two decades demonstrate the sea level rise（SLR） rate 3.2 ± 0.4 mm/a,of which1.8 ± 0.5 mm/a is contributed by the ice melting over land.This study shows that the oceanic thermal expansion is 1.0 ± 0.1 mm/a due to the temperature increase in recent half century,which coincides with the estimate provided by previous authors.The SLR observation by altimetry is not balanced by the ice melting and thermal expansion,which is an open problem before this study.However,in this study we infer that the oceanic part of the Earth is expanding at a rate about 0.4 mm/a.Combining the expansion rates of land part and oceanic part,we conclude that the Earth is expanding at a rate of 0.35 ± 0.47 mm/a in recent two decades.If the Earth expands at this rate,then the altimetry-observed SLR can be well explained.

SAR差分干涉测量技术及其在地表形变监测中的应用现状

合成孔径雷达差分干涉测量技术(D-InSAR)是一种新的空间对地观测技术.它利用合成孔径雷达(SAR)的相位信息提取地表的三维信息和高程变化信息,可以监测地球表面和冰雪表面的微小变化,且探测地球表面位移变化的精度可达到cm量级.因此,介绍了D-InSAR的基本原理和发展概况,综述了D-InSAR在地表形变监测中的应用现状,并对D-InSAR的应用前景进行了展望.

中心组合设计优化SG-5型PVC稀土复合热稳定剂的研究

采用正交设计与中心组合设计法优化了以硬脂肪酸镧、硬脂肪酸高铈、硬脂肪酸钕为复合热稳定剂的配方,得到了这三种稀土化合物对SG-5型PVC热稳定性产生作用的响应面图,探讨了稀土金属离子对PVC的稳定机理;检测了产品的性能。优化结果表明,以SG-5型PVC0.5g、硬脂肪酸镧为0.013g、硬脂肪酸钕0.0196g及硬脂肪酸高铈0.02g所组合得到的PVC树脂,其热稳定温度达到183.3℃,并能稳定35分钟以上,比正交实验结果180.8℃提高2.5℃,其力学性能优于正交结果。La3+、Ce4+、Nd3+对PVC树脂的热稳定作用与它们离子半径的大小及与自由基成键的能力和吸附能力呈正相关性。

厚黄土层深部开采覆岩和地表移动规律研究

为了揭示黄土层深部开采条件覆岩和地表移动规律,基于孟村矿401101工作面开采地质条件,采用地表实测和数值模拟相结合的方法,分析了煤层开采过程中地表移动盆地的分布和变化特征,计算确定了下沉、倾斜、曲率、水平移动和水平变形最大值;揭示了厚黄土层深部开采地表沉降量小、移动变形集中、地表移动前期具有突发性沉陷特点,确定了地表活跃阶段下沉量占沉陷总量的66.8%;确定了该矿地表移动角量参数和概率积分预计参数;研究了采动覆岩的位移和应力变化规律。研究成果可为该采区后续工作面和类似采矿条件矿井的开采规划设计和采动损害控制提供有益参考。

浙江省浦江县海豹岭脚S20省道滑坡成因及其治理

浦江海豹岭脚滑坡位于改（扩）建20省道K37＋180-K37＋250段南侧山坡上,为一小型牵引式土质滑坡。文章介绍了该滑坡的结构及变形特征,分析了滑坡形成的主要影响因素及滑坡形成机理;根据岩土样品的试验结果,结合地区经验值及反算值,确定计算滑坡稳定性及剩余滑坡推力的抗剪强度参数,采用瑞典条分法对两种不同工况下滑坡体进行稳定性计算。计算结果表明：在天然状态下,滑坡体处于欠稳定状态;在持续降雨时,滑坡体处于不稳定状态。结合工程实际对滑坡进行了治理设计,提出抗滑支挡结合地表排水的综合治理措施。

SNREI地球形变理论模拟研究进展

获取固体地球在内外力驱动下的形变特征是认识地球内部结构和动力过程的关键,全球和区域形变的观测与研究是高精度时空基准建立和维持的重要内容之一。本文系统介绍了地球形变理论模拟研究的主要进展,重点介绍了大气、海洋、陆地水和热在地表的负荷效应,以及内部的地震位错产生的形变问题。内容涉及基本的地球(热)弹性变形的初边值理论,及其有效求解方法与计算过程中遇到的困难及解决方案。最后在弹性形变的基础上,结合现今观测精度不断提高和人类活动对环境影响的背景,展望了未来在地球形变理论上的发展需求与应用前景。

基于升降轨D-InSAR获取台湾美浓M_W6.7地震同震形变场

D-InSAR技术能够在大范围内获取地表形变信息,但由于卫星侧视几何成像模式、研究区地形地貌等的影响,升降轨D-InSAR技术获取的地表形变存在差异。利用双轨D-InSAR技术对6景升降轨Sentinel-1A数据分别进行差分干涉处理,得到升降轨不同视线向上台湾美浓M_W 6.7地震区地表形变图,直观地再现了震区在2016年2月6日地震前后的地表变化。研究结果表明升轨D-InSAR监测到台湾地震造成的地表抬升最大达16 cm,降轨D-InSAR监测到地表下沉最大达-11 cm,联合升降轨数据,可获得较为真实的研究区地表形变。

DEM精度对D-InSAR提取地表形变的影响分析

从双轨法D-In SAR形变测量的原理出发,理论分析了外部DEM对双轨法D-In SAR提取地表形变的影响,得出外部DEM精度与地表形变误差之间存在线性函数关系,在其他参数不变的情况下外部DEM高程中误差越大所引起的形变误差就越大;探讨获取地表形变的技术流程,并结合实例分析了外部DEM对双轨法D-In SAR提取形变精度的影响,分析指出不同精度的外部DEM会直接影响到干涉条纹的数量、密度和质量。

Watershed systems science—A new paradigm to understand and govern the impact of human activities on the earth's surface in the Anthropocene

Recent scholars’work in Vol 58 Issue 1（2015）and Cheng and Li’s paper in Vol 58 Issue 7（2015）in Science China Earth Sciences propose development of＂Watershed science＂by＂Bridging new advances in hydrological science with good management of river basins＂.

Geophysical and Chemical Evidence in the Depletion of Ozone

The depletion of ozone is due to not only some chemical reaction, but also some physical changes, such as Solar Proton Events with solar flare, violent vortex of air currents with the changes of the earth’s rotation caused by earth’s deformation and so on We found that the tidal force by the sun makes the earth’s oblateness large on the 0° Latitude and small on the 23 5°Latitude The tidal force by the moon and nine planets can make this effect strong This is a basic reason for the creation of ozone hole and El Nino \;As shown from calculation,the earth tide by the sun makes the earth′s deformation and rotation change periodically.When the situation of the sun moves from 23.5°N to 23.5°S,the length of a day will change±0.00027s.When the earth moves from aphelion to perihelion,the length of a day will increase 0.00007s.The earth tide by the moon can increase or decrease this effect periodically.They are the reasons of the earth′s rotation decelerating from 30 July to 16 November and the ozone hole over the south Pole sky expanding with El Nino.The SSW unified stress field of the earth is the tectonic evidence of the orbital effect of the earth′s rotation and deformation.The moon′s declination and obliquity of the ecliptic determine the direction of the principal compressive stress field. Scientists discover chlorion layer in atmosphere while they studied freon.Chlorion can fly in to atmosphere from continent and ocean in many ways.The photolyte of freon is only one way of them,such as electrolysis and photolysis of sodium chloride and hydrogen chloride.The differential rotation of the earth’s layers mix ozone with chlorion and create a ozone hole over the Qinghai Tibet plateau sky.The depletion of ozone and El Nino are the results of the differential rotation.