The Sanjiang Plain is an important base of commodity grain production and contains lots of marsh wetlands in China. In the past 60 years, with the continuous increase of farmland area and the adjustment of planting structure, the decline of wetland and groundwater level has attracted great attention, whether the over-exploited groundwater is controversial. The remote sensing image data from 1956 to 2019 were selected to the analyze the evolution process characteristics of wetland and farmland using single land use dynamic degree. Based on the simultaneous measurement data in 1980 and 2019-2021 and the national groundwater monitoring project data, the influence of wetland reclamation on the groundwater level was explored. The results show that: (1) From 1956 to 2019, the marsh wetland presented a decreasing trend, while the dry land showed a trend of increasing first and then decreasing, and the paddy field had a trend of increasing first and then stabilizing. Sanjiang Plain was characterized by “wetland turning into dry land” with the area of 2.36×104 km2 from 1956 to 1996, while it presented “dry land turning into paddy field” with the area of 1.15×104 km2 from 1996 to 2019. (2) The decrease in groundwater level in the area of 36 546 km2 in the Sanjiang Plain from 1980 to 2021 was less than 5 m, and more than 10 m in the eastern area with 3 669 km2. The groundwater in the Jiansanjiang area is being over-exploited. (3) Compared with the groundwater level in the dry season in 1980, the groundwater depression cone area was 3 669 km2 in 2021 with the depth of 10 m as the standard, which was 269 km2 larger than that in 2019, and slightly expanded to the northeast direction. (4) In 2019, it was difficult to reach the natural regulation of “abundance to make up for deficiency” under the condition of heavy rainfall in the Jiansanjiang reclamation area, and the groundwater storage decreased by 5.81×108 m3. The results of this study provide a foundation for the study on regional water balance and are of great significance to the scientific understanding of the rational development and utilization of water and soil resources.

三江平原地下水开采量随着水稻种植规模快速扩张而大幅增加,2021年水位相对1980年下降5～12 m,是否因此引发地面形变甚至地面沉降成为社会关注的问题.采用二等水准测量方法和比拟法,分析研究了三江平原建三江垦区地下水位降落漏斗地面形变现状与发展趋势及危险性.研究表明,研究区50个二等水准测量点2019-2021年连续3期测量数据对比发现,地表垂向形变量整体较小(最大-18.00 mm,平均变化速率-4.6 mm/a).预测到2040年,地下水位降落漏斗中心水位埋深由2021年的19.88 m降至25 m左右,考虑到研究区"上粘下砂"的二元岩性结构,地下水位下降疏干的地层位于浅上部且厚度有限,地面沉降量仍较小,地质灾害发育程度弱、危险性小.本研究不仅回应了社会关切,也为进一步开展相关研究奠定了基础.

In recent years, groundwater levels in parts of the Sanjiang Plain has continuously decreased, which attracts great attention from scholars and related departments. In order to find out the temporal and spatial evolution of the groundwater flow field in the Sanjiang Plain and reveal its main influencing factors, in this paper the ArcGIS interpolation analysis, grid algebraic operations, comparative analysis and other methods are used to analyze the 72 groups of data in the Sanjiang Plain in 1980 and 1092 groups of groundwater level data and 44 groups of national groundwater monitoring data in the same period in 2019 and 2020. The spatio-temporal evolution characteristics of the groundwater flow field in the Sanjiang Plain are ascertained, and the control effects of different influencing factors on the smooth evolution of groundwater are clarified. The results show that, compared with 1980, the groundwater levels of the Sanjiang Plain showed an overall decreasing trend. The groundwater levels of the western plain area cumulatively decreased by 1 to 5 m, with an area of 2.6×104 km2, and most areas of the eastern Jiansanjiang reclamation area fell greater than 5 m with an area of 1.17×104 km2. Among them, the area where the cumulative drop of groundwater levels is greater than 10 m is as high as 3 400 km2, and the average annual drop of groundwater levels is about 0.29 m. Groundwater exploitation causes the changes in the groundwater flow field, and the hydrogeological conditions of "West Sand and East Stick" promote the temporal and spatial evolution of the regional groundwater level decline. The continuous expansion of the scale of paddy fields has caused over-exploitation of groundwater. The shallow surficial clay layer blocks replenishment from rainfall infiltration, and the groundwater cannot achieve self-balance with abundance to compensate for the shortage, resulting in the continuous decline in groundwater levels in the Jiansanjiang Reclamation Area. The results of this research lay a foundation for further investigation of the groundwater change laws and current characteristics of the Sanjiang Plain, and also provide technical support for scientifically guiding the rational development, utilization and management of groundwater resources.

确定潜水完整井单井抽水试验的渗透系数和影响半径,对潜水资源调查工作具有重要意义.依据水文地质资料,使用库萨金公式粗略计算了顺平县某单井的影响半径,分析了该井的α读数和自然电位特征,并利用抽水试验的观测井资料验证了α读数和自然电位与影响半径之间的对应关系.结果 表明:α读数和自然电位与抽水试验影响半径之间存在一定的对应关系,两者在抽水井处出现最大值,而从抽水井向影响半径边缘处其值逐步下降,最后接近自然背景值;潜水完整井稳定抽水试验中常用的库萨金公式准确度较低,使用α读数和自然电位来获取影响半径,其结果可靠,在条件类似的中、细砂潜水含水层分布区具有可推广性.

阜平县太古界变质岩经历了多期变质深熔作用,以揉塑性片麻岩为主,地层致密柔韧,富水性差,找水难度较大.在地质调查、物探勘探及钻探验证相结合的基础上,较系统地分析了变质岩区构造裂隙水、风化壳裂隙-孔隙水、层状裂隙水和接触型基岩裂隙水四种地下水类型的赋存规律及电性特征.结果 表明:构造裂隙水主要赋存在构造破碎带内;风化壳裂隙-孔隙水分布普遍,水量小,一般沟谷风化壳与断裂叠加带富水性较大;层状裂隙水和接触型基岩裂隙水主要赋存在硬脆-软塑岩性组合的接触带(面)上.在视电阻率等值线断面上,构造裂隙水呈现为陡降低阻带曲线;与构造复合的风化壳裂隙-孔隙水,呈现为凹型低阻曲线;层状裂隙水面状分布,呈现为水平低阻曲线;岩脉接触型基岩裂隙水,呈现为条带状高阻+类断层低阻反映.

在区域水文地质调查和探采结合井实例的基础上,基于蓄水构造理论,对阜平岩群变质岩区蓄水构造类型及其富水特征进行了分析,认为主要有风化壳蓄水构造、断裂蓄水构造、层状蓄水构造和岩脉蓄水构造4类.风化壳蓄水构造和断裂蓄水构造是主要找水方向.根据探采结合井的抽水试验数据,对地下水主要出水段埋深与标准井径降深涌水量的相关性进行分析,表明标准涌水量与出水段埋深呈幂级函数减小的趋势.

Through geothermal resources survey along the Qinghai-Tibet Railway( Nagqu-Lhasa section),it is found that there are nearly 40 of geothermal areas( points),of which five points are used for bathing and power generation. Through analysis on development and utilization of geothermal energy along the section,it is found the main problems in development and utilization of geothermal energy are:( 1) Unreasonable development and utilization;( 2) Low comprehensive utilization rate;( 3) Serious environmental and geological problems;( 4) Insufficient exploration of deep geothermal resources,especially hot dry rock.

Promotion of ecological civilization was initiated in the report to the 18th National Congress of the Communist Party of China.Therefore, geothermal resources, as an energy conserving and environmental new energy, are properly exploited and utilized has important practical significance and objective outlook. This paper analyses the problems occurred in the development and utilization of geothermal resources along the Qinghai-Tibet Railway in Tibet Autonomous Region, such as low-level of development and utilization, less and irrational utilization, low level of comprehensive utilization and serious waste of resources, insufficient use of geothermal resources, and poor development level. This paper puts forwards countermeasures aim at the problems above. These are: strengthening the recharge of generating tail water into geothermal field, and geothermal heating; making research on both the availability of useful element in the geothermal fluid, as well as geothermal theory and application technology.