1988年澜沧—耿马地震大地形变特征

1988年11月6日发生在云南省澜沧—耿马地区的两次强烈地震,其构造分型属雁列地震。7.6级地震的地表形变带呈“入”字形展布;7.2级地震的地表形变带反映单一发震构造特征。根据大地水平形变资料,主压应变轴为北东方向,地表形变带上存在明显的水平剪切错动;根据大地垂直形变资料,地表形变带无垂直向弹性差异形变,仅表现出一种重力堑的作用。本次地震序列所反映出来的大地形变基本特征与中国历次大陆地震相同。     

融合CORS网与时序InSAR研究北京地区地面形变

为提高地面形变监测的时空分辨率以及监测精度,采用CORS网与时序InSAR监测相融合的方法,对北京地区2018～2020年地面垂直方向形变进行研究。首先在InSAR监测量中去除极浅地表影响;然后对CORS站数据进行低频重构;最后以CORS网为基准,对InSAR监测时序进行整体平差,获得融合形变结果。结果表明,融合CORS网和InSAR监测能有效利用CORS网连续观测的优势,获取连续一致的高时空分辨率形变结果,融合方法在构建高分辨率与高精度地面形变时间序列中具有一定优势。在地面垂直方向上,朝阳区、通州区、大兴区中南部地面沉降最为明显,最大年平均形变速率达到-90 mm/a;昌平区中西部、海淀区西部、门头沟区东部等地存在较为明显的抬升,年平均形变速率约为10～20 mm/a;其他地区地面年平均形变速率约为-10～10 mm/a,相对变化较小,较为稳定。     

地面倾斜的形变特征及计算方法

对地倾斜的基本概念、形变特征以及计算方法作了系统的阐述,对地倾斜面的几何物理性质作了深入分析,并指出地面倾斜量是个伪矢量。最后,对地倾斜面的正演与反演问题进行了讨论。     

陕甘宁青地区的地形变特征与强震活动

分析了陕甘宁青地区的地壳形变特征及其与强震的关系．结果表明：(1)地壳形变特征存在时空差异性。不同地区地形变活动强弱与其至主要边界断裂带的距离存在相关性，主要边界断裂带附近地区相对活动强烈，远处则减弱。(2)不同时期各断层地形变活动强弱不同，既和构造应力场的变化有关，又与地震活动关系密切；断层垂直形变的逆继承性构造运动的活动时期远小于继承性构造运动的活动时期，且不同区域地壳构造运动发生转折的时间不尽相同，同时断层形变前兆异常亦存在时空差异性。(3)多场地、大范围的断层活动异常可能与强震活动相呼应。     

应用GPS监测城市地表形变的初步分析

根据实例,总体介绍了用ＧＰＳ监测城市地表形变的观测及数据处理方法。首先根据ＧＰＳ获得的基线结果进行３维自由网平差,由定期观测获得了各个监测点的水平位移和垂直位移。然后针对城市监测范围较小,在将其按照矩形格网划分后,给出了两种拟合方法：线性内插法和多面函数拟合法。据此,计算获得了城市地表的水平位移场和垂直位移（沉降）面,并对两种方法获得的结果作了比较。根据计算结果绘制了水平位移场、垂直沉降面及其等值线图,可以直观地了解地表形变信息。同时对于用ＧＰＳ监测城市形变的观测和数据处理中需要注意的问题作了简要的分析。     

某大型厂房地面垂直形变监测

结合西北地区黄土塬上某大型厂房地面垂直形变的监测工作,提出和应用选定在具有代表性的监测区域布点、改进标尺进行观测等一系列行之有效的方法和措施,取得了满意的结果。通过监测数据分析,指出型架的不稳定主要是因为温度变化而导致地面不均匀垂直形变引起的,为厂房地面不均匀垂直形变的治理提供了依据。     

甘宁青地区现今构造形变异常与地震

通过对甘宁青地区大地垂直形变，断层形变和GPS水平形变测量资料的处理分析。结合地质构造和有形变资料积累以来本区域多次中，强地震活动，对本区现今构造形变异常与中强以上地震蕴育的一些特征进行了初步研究和探讨。结果表明：（1）甘宁青监测区主要断裂附近构造形变相对强烈；垂直差异运动强度和变形态势随时间演变，水平运动变形呈明显的挤压走滑特征。（2）本区构造形变与地震蕴育的主控应力来自青藏块体持续NE向挤压运动；构造形变和地震活动的时空分布演化与块体活动及区域构造应力场动态演化密切相关。（3）区域构造块体边界地带出现的异常隆起与高梯度形变带及显著的断层形变异常，是蕴育中，强震的标志，但地震并不一定发生在幅度最大的部位，而往往发生在断层形变异常呈现“趋势积累－加速－转折”变化特征的地段及附近，在此基础上，对研究区强震危险性进行了初步预测。     

中国大陆现今垂直形变特征的初步探讨

利用GPS观测资料进行大范围的垂直形变特征研究是本文研究的重点。通过网络工程基准站和基本站的GPS观测资料，绘制了中国大陆的垂直速率等值线图像，并对中国大陆垂直运动特征进行了定性的分析，结果表明：中国大陆垂直运动在70％以上的区域表现为沉降运动，在青藏高原和除北京外的整个华北块体及燕山块体的垂直运动表现为隆升的趋势。中国大陆西北和东南、西南和东北的整体垂直运动呈一种斜对称状态。对基于GPS观测所得的等值线图与基于水观测所得的等值线图进行了比较，比较结果显示，除了华南块体外，二者在整体趋势上比较一致。     

新疆拜城黑孜尔水库垂直形变观测与现今断层活动特征

根据跨断层定点水准、基线观测资料和垂直形变的水准高程观测数据分析,黑孜尔断裂 Ｆ２定点水准的垂直位移量为 ０． １４ ｍｍ／ａ,基线缩短量为 ０． ４８ ｍｍ／ａ,断层滑动角■≈３７°,现今垂直形变速率为 ０． ６９３ ｍｍ／ａ。结合地震活动和区域地质构造研究,认为黑孜尔断裂近期水平活动强度大于垂直运动强度,该区在未来１～３年内仍可能发生６级以上地震。     

Prediction of surface subsidence in Changchun City based on LSTM network

Monitoring and predicting of urban surface subsidence are important for urban disaster prevention and mitigation.In this paper,the Long Short-Term Memory(LSTM) network was used to predict the surface subsidence process of Changchun City from 2018 to 2020 based on PS-InSAR monitoring data.The results show that the prediction error of 57.89% of PS points in the LSTM network was less than 1mm with the average error of 1.8 mm and the standard deviation of 2.8 mm.The accuracy and reliability of the p...     

三峡库区麻柳林滑坡变形特征及演化模拟

在库水位波动和降雨作用的共同影响下，库岸滑坡的变形规律往往更为复杂。以三峡库区麻柳林滑坡为例，基于野外调查、钻探编录、深部位移监测以及数值模拟等手段，分析了库水位波动和降雨作用下滑坡变形特征及演化规律。结果表明:麻柳林滑坡在粉质黏土层和块石层交界处发育一个次级滑带，目前该滑坡主要沿次级滑带运动，导致次级滑动的原因与坡体物质的差异性有关；S_i(S_f)指标分析法揭示滑坡的滑带还未完全破坏，滑坡仍处于蠕变状态；根据三峡水库水位调度规律，将一个完整水文年划分为6个阶段，数值模拟结果表明滑坡在库水位缓慢下降阶段变形速率较小、在快速下降阶段和低水位阶段变形速率持续增大、在快速上升阶段和缓慢上升阶段以及高水位阶段变形速率则保持平稳。其中，降雨的直接影响和降雨导致库水位波动进而对滑坡变形造成的间接影响，使得麻柳林滑坡在低水位阶段的变形显著增加、稳定性最差，应加强该时段内滑坡的监测和预警。      

DRASTIC-based vulnerability evaluation for groundwater environment in Kunming City

Groundwater pollution has serious influences on programming and development for a city. So it has a special importance to assess reasonably the vulnerability to pollution for urban groundwater. DRASTIC is an effective method for groundwater vulnerability assessment, which has been adapted in USA and Europe countries. In this paper, DRASTIC method is applied in vulnerability assessment of shallow groundwater environment in Kunming. A total of 1 339 units are divided in this area and the grade of each unit for seven indexes is determined. Then vulnerability zones are divided in the area by DRASTIC value, which has an important meaning to city programming.     

DRASTIC-based vulnerability evaluation for groundwater environment in Kunming City

Groundwater pollution has serious influences on programming and development for a city.So it has a special importance to assess reasonably the vulnerability to pollution for urban groundwater.DRASTIC is an effective method for groundwater vulnerability assessment,which has been adapted in USA and Europe countries.In this paper,DRASTIC method is applied in vulnerability assessment of shallow groundwater environment in Kunming.A total of 1 339 units are divided in this area and the grade of each unit for seven indexes is determined.Then vulnerability zones are divided in the area by DRASTIC value,which has an important meaning to city programming.     

Distribution and accumulation characteristics of heavy metals in sediments in southern sea area of Huludao City, China

The southern sea area of the Huludao City, Liaoning Province might be polluted by heavy metals because it is close to the Jinzhou Bay, one of the heaviest sea area polluted by heavy metals in China. The undisturbed modern sediment core can be used to analyze the accumulation and source of the pollutants using 137 Cs and 210 Pb ex . Thirty-five samples of surface sediment and two core sediments were collected from the southern sea area of Huludao City. The concentrations of copper (Cu), lead (Pb), chrome (Cr), zinc (Zn), arsenic (As) and mercury (Hg) in the surface sediments as well as Cu, Pb, Zn, Cr, 137 Cs and 210 Pb ex in the core sediments were determined to research the spatial distribution and accumulation characteristics, and to analyze the sources and the potential risks of heavy metals. The results show that the pollution levels of Zn and Hg are serious, and 26 stations are at moderate or heavy ecological risks. The concentrations of the heavy metals increase from east to west, as well as from open sea to offshore marine area. The concentrations of heavy metals are not high in the sediments adjacent to the Jinzhou Bay, and the influence caused by the seawater exchange with the Jinzhou Bay is little. The concentrations of the heavy metals in the core sediments show low-high-low characteristic, and it coincides with the pollution history of Huludao City. The atmospheric deposition of heavy metals from the Huludao Zinc Plant is likely to be the main source of pollution without direct discharge of wastewater. The high concentrations of heavy metals appear on the upper sediment of 20 cm. The shallow sediment with high heavy metal contents might be exposed to surface when it was disturbed by the ocean engineering and big storm surge, then cause risk to the safety of aquaculture and human healthy.     

东非裂谷系Albert湖凹陷新生代构造沉降特征

新生代形成的东非裂谷是威尔逊旋回萌芽阶段的典型陆内裂谷,长期以来备受国内外地质学家关注。Albert湖凹陷位于东非裂谷系的西支最北端,整体呈北西向带状展布的不对称(半)地堑。目前,该区已有较好的工业性油气发现,分析其沉降演化规律对进一步揭示该凹陷的构造沉降特征及其油气勘探潜力具有重要的意义。基于钻井资料,结合地震资料解释、沉降史、埋藏史与断层活动性分析,重新划分了构造单元,总结了构造沉降特征,探讨了沉降与断裂的关系、沉降中心迁移的规律及其对油气勘探的指示意义。研究表明:Albert湖凹陷东部的次级构造单元主要受到东部边界断裂的控制,F₁、F₂断层对东部陡断带、东部断阶带以及三个构造调节带的沉降变化及其形成起主要控制作用;南部次凹在早期沉降速率较大,有利于晚中新世形成巨厚的烃源岩,随着沉降中心向北迁移,北部次凹发育了上中新统和下上新统烃源岩;沉降中心周缘的构造带是油气运聚的有利指向区。研究成果为东非裂谷系Albert湖凹陷油气进一步勘探提供了新的依据。      

Suitability planning of urban underground space exploiting based on extenics of Kunming City

The subways or underground construction have been built nationwide in 25 cities.The pre-assess-ment and systematic planning are requested for building a new metro lines.The reason is the inevitability that new construction projects have to face the various difficulties and geological environment risks in accordance with their diverse urban geological environment under underground space development and construction.Taking the Kumming City planning as an example,the study assesses the suitability and analyzes its high risk factors on urban underground space development and utilization,using the extenics research methods under complex geological conditions.It would provide a reference to underground space development in the similar urban geological conditions.     

Spatial-temporal characteristics of land subsidence corresponding to dynamic groundwater funnel in Beijing Municipality,China

Due to long-term over-exploitation of groundwater in Beijing Municipality,regional groundwater funnels have formed and land subsidence has been induced.By combining a groundwater monitoring network,GPS monitor-ing network data,radar satellite SAR data,GIS and other new technologies,a coupled process model based on the dy-namic variation of groundwater and the deformation response of land subsidence has been established.The dynamic variation of groundwater funnels and the land subsidence response process were analyzed systematically in Beijing.Study results indicate that current groundwater funnel areas are distributed mainly in the southwest of Shunyi District,the northeast of Chaoyang District and the northwest of Tongzhou District,with an average decline rate of groundwa-ter level of 2.66 m/yr and a maximum of 3.82 m/yr in the center of the funnels.Seasonal and interannual differences exist in the response model of land subsidence to groundwater funnels with uneven spatial and temporal distribution,where the maximum land subsidence rate was about-41.08 mm/yr and the area with a subsidence rate greater than 30 mm/yr was about 1637.29 km2.Although a consistency was revealed to exist between a groundwater funnel and the spatial distribution characteristics of the corresponding land subsidence funnel,this consistency was not perfect.The results showed that the response model of land subsidence to the dynamic variation of groundwater was more revealing when combining conventional technologies with InSAR,GIS,GPS,providing a new strategy for environmental and hydrogeological research and a scientific basis for regional land subsidence control.     

北京新航城地区地面沉降演化规律及多源监测方法对比研究

为查明北京新航城地区地面沉降演化规律,结合基岩标-分层标和水准测量对新航城地区地面沉降特征进行了分析,并结合不同监测方法进行了对比研究评价。研究发现:①近十年新航城地区浅部地层中沉降量和沉降比例越来越小,沉降比例由2009年67.62%下降到2019年19.69%,而中部地层和深部地层则随着时间沉降量和沉降比例越来越大,中部地层沉降比例由2009年21.39%增加到2019年35.83%,深部地层沉降比例则由2009年10.99%增加到2019年44.48%;浅部地层含水层水位呈现周期性往复变化,中部和深部地层含水层在周期性变化中持续下降,地层在水位周期性往复变化中持续压缩。②根据历年水准测量和地下水动态监测成果,研究区自北向南累计沉降量逐渐减小。地面沉降和地下水位数据拟合后发现二者具有一定的相关性,相关性随着水位降幅的增大,相关性也随之增大,二者成正相关。③基岩标—分层标静力水准测量系统与人工水准测量系统对同一监测点和不同深度数据互校后的误差值非常接近,符合正态分布规律,不同深度的监测数据相关系数为0.993 6;对比2种方法各有优势与不足,应根据实际情况,多方面获取沉降信息与数据,满足地区级地面沉降监测与防治的不同需求。      

Chemical characteristics of aerosols in the Kuroshio area

Aerosol samples were collected with a Sierrer Model 235 cascade impactor in the marine atmosphere over the Kuroshio area in consecutive four seasons from 1987 to 1988. Na, Cl, Al, V, and water soluble and acid soluble Mn, Fe, Pb, Cu, V, Cd were determined by neutron activation analysis and atomic absorption spectrophotometry, respectively. Seawater source chemical species in the aerosols appeared in high content in large over 3.6 μm diameter particles, and crustal source vanadium appeared in 3.6 μm diameter particles, but pollution source vanadium appeared in less than 0.52 μm diameter particles. Trace metals in the aerosols mostly had the highest concentration of water soluble metals on fine particles, and acid soluble metals on large particles. The concentrations of trace metals in the aerosols were higher in autumn and winter, lower in spring and summer. Funds from the National Natural Science Foundation of China.