[Objective]The mountainous and hilly areas of western Zhengzhou City have a complex geological environment,affected by rainfall and human engineering activities.Geological hazards such as collapses,landslides,and debris flows occur frequently.In particular,the"7·20"extreme rainstorm that occurred on July 20,2021 caused many geological hazards,resulting in heavy casualties and huge economic losses.Therefore,analyzing and summarizing the development characteristics of geological hazards and conducting a risk assessment is necessary for this region.At present,the risk assessment of geological hazards is mainly conducted using a single method that has limitations including slightly low evaluation accuracy.In addition,an overall geological hazard risk assessment has not yet been conducted in the mountainous and hilly areas of western Zhengzhou City.[Methods]Based on the research and analysis of the geological environment background and the distribution characteristics of geological hazards in the study area,eight evaluation factors were selected:slope,landform,engineering geological rock group,elevation,distance from fault,distance from river,rainfall,and human engineering activities.The weighted information method which incorporates elements of the information quantity model and analytic hierarchy process,was used to evaluate the risk of geological hazards in the study area.[Results]The low-,medium-,and high-risk areas are 1387.14 km2,1803.18 km2,and 1066.47 km2,respectively,accounting for 32.59%,42.36%,and 25.05%of the total area,respectively.The medium-and high-risk areas are mainly distributed in the tectonic erosion medium-low mountains and loess hills in the central part of the four cities,the tectonic erosion medium-low mountains south of Dengfeng,and the loess hilly areas in northern Gongyi and Xingyang.The terrain has steep slopes and deep gullies,and the main stratigraphic lithology is clastic rocks intercalated with carbonate rocks,soft and hard rock layers,and loess.Fault structures are developed,and geological hazards are prone to occur under the action of inducing factors and are highly dangerous.The majority(93.11%)of geological hazards are distributed in medium-and high-risk areas,with hazard point densities of 0.1752 km-2 and 0.2869 km-2,respectively.The spatial distribution of geological hazard points is consistent with the geological hazard risk assessment results.The rationality of the evaluation results was assessed by a Receiver Operating Characteristic curve,yielding an AUC value of 0.868.The evaluation accuracy met the requirements for hazard assessment.[Conclusion]Geological hazards have the largest information value in the range of>40°slopes loess hilly landforms,loess engineering geological rock groups,and 24-h maximum rainfall of 500-550 mm.The risk of geological hazards is positively correlated with distance from faults and water systems—the closer the distance,the higher the risk.The risk of geological disasters in the study area is controlled by the terrain slope and landform and is closely related to the lithology of the formation,which is an important factor in inducing geological disasters.The weighted information method,which has high accuracy and rationality,was used to evaluate the geological hazard risk.[Significance]The results of this study can provide a basis and technical support for geological hazard prevention and management in the mountainous and hilly areas of western Zhengzhou City and serve as a valuable point of reference for urban planning and infrastructure geological hazard risk assessment in the study area.

With the rapid socio-economic development and urban expansion, land subsidence has emerged as a major environmental issue, impeding the high-quality development of the plain area in eastern Zhengzhou City, Henan Province, China. However, effective prevention and control of land subsidence in this region have been challenging due to the lack of comprehensive surface deformations monitoring and the quantitative analysis of the factors driving these deformations. In order to accurately identify the dominant factor driving surface deformations in the study area, this study utilized the Persistent Scattered Interferometric Synthetic Aperture Radar (PS-InSAR) technique to acquire the spatio-temporal distribution of surface deformations from January 2018 to March 2020. The acquired data was verified using leveling data. Subsequently, GIS spatial analysis was employed to investigate the responses of surface deformations to the driving factors. The findings are as follows: Finally, the geographical detector model was utilized to quantify the contributions of the driving factors and reveal the mechanisms of their interactions. The findings are as follows: (1) Surface deformations in the study area are dominated by land subsidence, concentrated mainly in Zhongmu County, with a deformation rate of −12.5–−37.1 mm/a. In contrast, areas experiencing surface uplift are primarily located downtown, with deformation rates ranging from 0 mm to 8 mm; (2) Groundwater level, lithology, and urban construction exhibit strong spatial correlations with cumulative deformation amplitude; (3) Groundwater level of the second aquifer group is the primary driver of spatially stratified heterogeneity in surface deformations, with a contributive degree of 0.5328. The contributive degrees of driving factors are significantly enhanced through interactions. Groundwater level and the cohesive soil thickness in the second aquifer group show the strongest interactions in the study area. Their total contributive degree increases to 0.5722 after interactions, establishing them as the primary factors influencing surface deformation patterns in the study area. The results of this study can provide a theoretical basis and scientific support for precise prevention and control measures against land subsidence in the study area, as well as contributing to research on the underlying mechanisms.

Objectives: The rock—soil strata constitute the basic material environment of the underground space and have a huge impact on the development and utilization of the underground space. Therefore, in-depth understanding and analysis of the structural characteristics of the rock—soil strata can lay a solid foundation for the development of the underground space.Methods: The urban area of Zhengzhou mainly distributes loose strata such as silt, silty clay, clay, silty sand, medium—coarse sand, and some special soils such as soft soil and collapsible loess. According to the vertical combination of rock and soil strata, it is divided into single-layer structure, double-layer structure, triple-layer structure and multiple-layer structure. Then, the stratigraphic structure of the underground space in Zhengzhou urban area is discussed separately according to the shallow layer（0～-15 m）, the sub-shallow layer（-15～-30 m） and the sub-deep layer（-30～-50 m）.Results: The shallow（0～-15 m） underground space stratigraphic structure in Zhengzhou City is divided into 3 regions, 6 sub-regions and 25 structural sections; the sub-shallow（-15 ～-30 m） underground space stratigraphic structure is divided into 2 regions and 28 sub-regions; the sub-deep（-15 ～-30 m） underground space stratigraphic structure is divided into 2 regions and 31 sub-regions. It provides accurate geological data and technical support for the development and utilization of underground space in Zhengzhou city.Conclusions: The overall structure of the underground space in Zhengzhou is relatively simple, the cost and risk of development are low, and it has great potential for development and utilization. Overall, the western piedmont alluvial and diluvial plain area is more suitable for underground space development and utilization than the eastern Yellow River alluvial plain area.Based on the stratigraphic structure characteristics of different urban areas, the following suggestions for the development and utilization of underground space are put forward: focus on the development and construction of underground storage and underground energy production facilities in the western new urban area; build underground water storage pipe gallery and deep drainage in the main urban area; north of the Lianhuo Expressway in the eastern new urban area as an avoidance area for underground space development; the Aviation city focuses on the construction of underground storage, modern logistics channels and other facilities. And the influence of stratigraphic structure on the construction of sponge city and road collapse in Zhengzhou is discussed.

地下水是维持人类生存和发展的重要资源.近年来,由于人类活动的强烈干扰,导致地下水的水化学特征发生改变,严重影响了其使用价值和生态功能.本研究以郑州市中牟县作为研究地区,联合应用Piper三线图、Gibbs图、离子比例系数法和多元统计技术,探究该地区地下水化学演变特征及形成机制,结果表明,中牟县地下水主要的阳离子是Ca2+和Na+,主要的阴离子是HCO3-和Cl-.地下水主要的水化学类型为HCO3-Ca(Mg)型,占总水样的46.2％.农业用地受到施肥的影响,水化学类型出现了Cl型水(20.8％)和SO4型水(6.25％),住宅用地由于受到生活污水的影响,出现了高比例的Na型水(55.0％).而在湿地,地下水受到黄河水和污水处理厂回水混合影响,导致其主要的水化学类型转变为HCO3-Ca(Mg)·Na型.中牟县地下水水化学组分主要控制因素是岩石风化作用,并且主要受控于硅酸盐岩风化,而人类活动对水化学组分也存在一定的影响.相关性分析表明,在不同土地利用类型下,除NH4+、NO3-和NO2-外,其余水化学组分之间表现出显著的正相关关系,表征它们主要来自地层岩石风化.NH4+和NO3-表现出显著的负相关关系,说明二者主要来自于化肥和生活污水.在农业用地和住宅用地中地下水可能发生强烈的硝化作用,但是,湿地地下水可能发生了反硝化作用.研究结果可为中牟县地下水可持续开发利用提供理论依据和数据支撑.

河南郑州"7?20"特大暴雨后,城市内涝灾害如何防范,海绵城市如何发挥减灾作用广受关注.郑州是全国首批开展多要素城市地质调查的示范城市之一.中国地质调查局与河南省自然资源厅、郑州市政府构建联动机制,在"空间、资源、环境、灾害"等方面统筹部署地质调查工作,为该市规划、建设、运行和管理提供自然资源和地质环境保障.

海绵城市规划建设过程中,自然及地质背景条件对低影响开发设施的布设具有重要影响.针对郑州市的1945 km2海绵城市规划区,根据海绵城市建设要达到的蓄水、渗水、净水等功能,分析地表植被、地形坡度、包气带及含水层等海绵特性,构建了基于海绵城市建设的地质适宜性评价体系,并用层次分析法进行评价,结果表明:郑州市海绵城市建设地质适宜性好的区域面积占规划区的3.83％,适宜性较好区域占33.12％,适宜性中等区域占54.05％,适宜性差区域占9.00％;郑州市规划的12个海绵城市重点建设区,有2个覆盖不适宜建设区,分布在龙湖片区西北部和双鹤湖片区;航空港区有建设海绵城市的天然条件,建议在东湖节点周围规划海绵重点建设区.海绵城市建设的地质适宜性评价结果对郑州市海绵城市规划建设有参考意义.

论文以华北平原某垃圾场为例,选取低环萘(2环)和高环苯并[ghi]苝(6环)即迁移能力最强与最弱的两类多环芳烃的代表性物质为研究对象,采用0.01mol/LCaCl2溶液与垃圾渗滤液两种背景溶液,通过试验分析黏性土对多环芳烃吸附动力学、等温吸附性,揭示出垃圾渗滤液中多环芳烃在包气带黏性土中吸附规律和机理,这一研究对探讨黏性土吸附垃圾中多环芳烃的阻隔规律和地下水污染防治具有重要意义.

第四系松散地层对工程建设、城市发展等影响较大,一些地区的沉积环境较复杂,给划分了解其地层层序变化带来很大困难.借助有限测年资料等,仅能反映样点附近情况,且费用很高.以郑州航空港北部一带为例,在深入分析其地质调查资料并结合对周边地质环境的成熟认知,以及现有关于第四纪时代划分与冷、暖气候变化认识等基础上,改进了一套由一系列关键划定步骤接续组成的,以侧重反映地层成因、岩性特征、沉积旋回变化,并含括地质构造运动、气候变化、地层年代信息等内容的地层层序划定方法,解决了上述难题.新方法划定结果符合区域地质环境的演进特征.一些特征明显的地层可在认识成熟的周边地区或地层组中找到印证,连同其他重要地质信息,可基本控制满足地层划分对地质年代的精度要求.

通过对洛阳市某PTA化工厂进行工程勘察和吸附实验、生物降解实验、土柱淋滤实验求取了包气带物质运移的相关参数,利用Hydrus-1D软件对CODcr在蓄水池下包气带中的迁移进行了模拟预测.结果显示,不采取防渗措施时,正常工况、非正常工况、一般事故和风险事故4种工况下,CODCr从蓄水池底部超标迁移至潜水所需要的时间分别为5.4a、5 a、4.9a、3.8a,该污水蓄水池污染当地地下水风险很高;若在蓄水池下铺设2.5m厚的黏性土垫层,则四种工况下CODCr从蓄水池底部超标迁移至潜水所需要的时间分别为12.2a、10.5 a、9.1a、6.8a.

PTA wastewater discharged from a factory was selected as the research object in this project and CODcr was selected as the characteristic pollution factor. Static adsorption and soil column leaching experiments of silty clay and clayey soil were carried out to study the adsorption, bio-degradation and dispersion coefficient of CODcr in PTA wastewater. Hydrus-1D was used to build the convection-diffusion model to demonstrate the migration of PTA wastewater in the vadose zone. The results indicate that silty clay and clayey soil in the vadose zone can adsorb, degrade and impede the contaminants in PTA wastewater; however, the coefficient of adsorption and degradation were very low, they were down to 0.0002 L g(-1), 0.0003 L g(-1) and 0.0097 d(-1), 0.0077 d(-1) for silty clay and clayey soil, respectively. Under the virtual condition that, wastewater in the sewage pool is 5 m deep, CODcr concentration is 4000 mg L-1, vadose zone is 21 m, PTA wastewater will reach the phreatic surface after 20.87 years. When wastewater in the sewage pool is 7 m with other conditions unchanged, after 17.18 years PTA wastewater will reach groundwater. The results show that there is a higher pollution risk for groundwater if we do not take any anti-seepage measures.

The PTA wastewater discharged from a factory is selected as the research object, COD is selected as the characteristic pollution factor of PTA wastewater. Static adsorption and soil column leaching experiment of silty clay were taken place to study the adsorption、bio-degradation and dispersion coefficient of PTA wastewater. The Hydrus-1D soft was used to build the Convection-Diffusion model to demonstrate the phenomena of PTA wastewater migration, to predict the regularity of PTA wastewater migration in vadose zone. The results indicated that the silty clay in vadose zone could adsorb、degrade and impede contaminant in PTA wastewater, but the coefficient of adsorption and degradation were very low, down to 0.256cm3/g and 0.0077d-1respectively. When COD concentration is 4000mg/L, PTA wastewater is 5m deep in the tank and vadose zone is 10m thick, COD concentration will exceed standard after 11.76 years.

Adsorption behavior of Cr (Ⅵ) in vadose zone, which is silty clay and clayey soil, was studied through kinetics experiments, isothermal adsorption experiments under various conditions, including different ph, temperature and organic contents. The results from kinetics experiments showed that the sorption progress of Cr (Ⅵ) has clear features in different stages, and adsorption equilibrium showed at 30 min, the adsorption rate of silty clay and clayey soil were 60%. The isothermal adsorption curve of Cr (Ⅵ) fitted closely with Freundlich equation model. When pH is 3-5 a plateau were seen, thereafter with increase in pH the adsorption rate of Cr (Ⅵ) dropped sharply and the minimum achieved at pH 10, the adsorption rate were only 35%. Adsorption rate of Cr (Ⅵ) increased gradually with the increase of temperature, the temperature of vadose zone is 14.7 ℃, according to the experimental results, the adsorption rate of Cr (Ⅵ) is about 40%. The use of organics represents an important contribution to the sorption of Cr (Ⅵ), sorption rate up to 100% when 30% of organic content. These studies will provide basis for manager to minimize the impacts, and provide basic data for pollution prevention and remediation of vadose zone.

The pattern of adsorption,degradation and migration of CODCr of the wastewater was examined through the static batch experiments and the soil column methods,and the parameters required with the numerical simulation were obtained.As a result,the partition coefficients,longitudinal dispersivity and the first-order degradation coefficient of CODCr on silt were 0.155cm3/g,0.15cm,and 0.009 7/d,respectively.The migration of CODCr in the soil columns was simulated with the Hydrus-1D software.The results show that a good correlation exists between the measured values and the simulated ones.The migration depths within different times were predicted by the correspondence mathematical models.