深井热水开采对豫01井水位影响的探讨

河南省濮阳地区地下热水的开采对处于同水层的地震观测井—豫01井水位观测产生了严重的干扰影响。豫01井水位自1996年9月出现下降变化以来,其水位动态一直受到大家的关注。十几年来,地震界专家学者对有可能影响该井水位动态的诸多因素逐一进行了追踪研究。认为豫01井自1996年9月至今水位变化与中原油田抽水、注水、采油无关;其...     

京北地热田开发对地下流体动态的影响

在地震地下流体动态研究中发现有多种干扰,特别是地下水资源开发的干扰较为普遍,地下热水开发的干扰较为严重,影响地下流体动态监测的效果,因此需要关注、调查与研究地下水开采对地下流体动态的影响问题。作者在研究京北地热田区水文地质条件及热水开采的历史与现状的基础上,重点分析了热水开采对不同水文地质条件与离开采井距离不等的观测井地下流体动态的影响及这种影响在不同测项上表现的差异。研究结果表明,在京北地热田区热水开采对地下流体动态的影响距离为5km,对位于导水断裂带附近的观测井动态影响最为明显;就测项而言,对水位与水温动态的影响最为明显,其次是逸出气(Rn,Hg)动态的影响,对土壤气(CO2)动态的影响不明显     

豫01井水位急剧下降原因调查与分析

通过对豫01井39年井水位动态趋势变化分析,结合对周边观测环境调查、01井含水层地下水补给与排泄情况调查与分析,得出引起2006年以来豫01井水位急剧趋势性下降的主要影响因素为地下水大量开采使用,其次为煤炭开采排水,排除地震前兆异常。      

太平庄井地下流体动态主要干扰因素研究

通过分析多年的观测资料，认为太平庄井地下流体动态的主要干扰因素为区域地下热水开采，其次为降雨。气压的明显变化对水位、水温也有一定干扰。区域开采造成太平庄井水位、水温同步下降，氢气测值升高；降雨导致太平庄井水位上升、水温下降。     

赵各庄井水温动态主要干扰因素研究

赵各庄井由浅层冷水和深部热水混合,周边村庄和农用抽水井对其有干扰。受地下水开采影响,2002—2011年6月,水位、水温呈下降趋势,且3月中下旬出现水位下降,水温上升,可用冷热水混合机理进行解释,即浅层冷水被开采,井水位下降,井区流入井筒内的冷水比例变小,水温上升。该井还受降雨的影响,每年6月中下旬,水位上升,水温变化多样,推测与降雨强度及其分布有关。2002—2004,2008—2010及2014年,降雨量少,水位上升小,水温变化平稳;2005—2007及2011—2013年,降雨量大且分布集中,水位快速、大幅回升,水温快速下降后缓升至平稳。对水温动态的分析中应重视对干扰因素的研究,正确识别干扰,积累相似干扰,总结受干扰影响的形态特征,为排除干扰、提取正常动态规律提供了新的方法。     

新泽5井除油工具研制

新泽5井是石油勘探井,井深达3 364m,有少量石油渗出,需要定时人工除油。由于该井水位下降幅度较大,原有的除油工具不能使用,使得井管内积油逐渐增多,影响了观测资料质量。为此研制了新泽5井除油工具并进行了初步试验。结果表明,除油效果较佳。     

河北新泽5井数字化观测装置的改进与分析

介绍了河北新泽5井石油探测井的概况，分析了2002年12月中旬该井数字化观测和模拟观测失真的原因。提出了对数字化观测仪器改进的方案。采取把数字探头安装到主井管中，将探头置于一个特制的套管内，对主副井管内的原油进行了清理等办法，使新泽5井水位数字化和模拟观测恢复正常。得出此法对河北新泽5井而言是可行的结论。     

马16井开采对马17井水动态观测的影响

为了验证平原地区深井水动态观测受环境条件影响的情况,我们选择了河北省河间地区马17地震观测井和马16地热开发井进行对比观测,试图探讨马16井开采对马17井水动态观测的影响。结果表明马17井的动水位年变化是气压干扰所致,与马16井采水无明显关系。马16井冬季开采热水对马17井动水位观测无明显影响。     

豫01井水位动态趋势下降因素探讨

探讨了河南范县豫０１井水位自１９９６年９月份以来持续下降的原因,对有可能影响该井水位动态的诸多因素逐一进行了对比分析和研究,认为范县豫０１井自１９９６年９月至今的水位下降与中原油田抽水、注水、采油无关;而当地降雨降荷载效应外没有短期渗流反映;山西长治一带降雨量变化与豫０１井的水位变化基本无关;山东梁册县９７井水位动态与豫０１井水位动太县有较好的一致性,表明山东梁山是豫０１井地下水的补级源,指出该井１９９６年９月至今的水位趋势下降主要是１９９７年干旱、降雨量减少,地下水不能充分地补给所致,亦可能与近年来范地区地壳应力活动增强有关。     

太平庄观测井地下流体动态综合研究

太平庄观测井是一口有十几年观测资料并有几次较好震例的综合观测井。近年来 ,由于地下水的大量开采 ,使得地下水位大幅度下降 ,尤其是观测井周围地热的开采 ,对太平庄观测井的正常动态影响较大。文中结合往年较正常的动态特征和地质构造等 ,分析了太平庄观测井的水位、水温、逸出气和断层气等的年动态变化特征。结果表明 :水位、水温的变化规律受观测井水位补给区降雨量的影响 ,水温还受当地降雨量的影响 ,特别是太平庄观测井周围新井的抽水对水温、水位、逸出气均有一定影响。由于观测井受诸多因素的影响 ,导致太平庄观测井的观测资料不能按往年的变化规律进行动态分析。在排除了降雨和人为的干扰因素外 ,太平庄观测井的资料动态趋势还可用于首都圈的震情预测     

Source and Quality of Groundwater Surrounding the Qinghai Lake,NE Qinghai-Tibet Plateau

Comprehensive studies on the spatial distribution, water quality, recharge source, and hydrochemical evolution of regional groundwater form the foundation of rational utilization of groundwater resources. In this study, we investigated the water levels, hydrochemistry, and stable isotope composition of groundwater in the vicinity of the Qinghai Lake in China to reveal its recharge sources, hydrochemical evolution, and water quality. The level of groundwater relative to the level of water in the Qinghai Lake ranged from −1.27 to 122.91 m, indicating most of the groundwater to be flowing into the lake. The local evaporation line (LEL) of groundwater was simulated as δ²H = 6.08 δ¹⁸O-3.01. The groundwater surrounding the Qinghai Lake was primarily recharged through local precipitation at different altitudes. The hydrochemical type of most of the groundwater samples was Ca-Mg-HCO₃; the hydrochemistry was primarily controlled by carbonate dissolution during runoff. At several locations, the ionic concentrations in groundwater exceeded the current drinking water standards making it unsuitable for drinking. The main source of nitrate in groundwater surrounding the Qinghai Lake was animal feces and sewage, suggesting that groundwater pollution should be mitigated in areas practicing animal husbandry in the Qinghai-Tibet Plateau, regardless of industrial and urbanization rates being relatively low in the region. The scientific planning, engineering, and management of livestock manure and wastewater discharge from animal husbandry practices is a crucial and is urgently required in the Tibetan Plateau.     

Tidal effects on groundwater dynamics in unconfined aquifers

The variation of seawater level resulting from tidal fluctuations is usually neglected in regional groundwater flow studies. Although the tidal oscillation is damped near the shoreline, there is a quasi‐steady‐state rise in the mean water‐table position, which may have an influence on regional groundwater flow. In this paper the effects of tidal fluctuations on groundwater hydraulics are investigated using a variably saturated numerical model that includes the effects of a realistic mild beach slope, seepage face and the unsaturated zone. In particular the impact of these factors on the velocity field in the aquifer is assessed. Simulations show that the tidal fluctuation has substantial consequences for the local velocity field in the vicinity of the exit face, which affects the nearshore migration of contaminant in coastal aquifers. An overheight in the water table as a result of the tidal fluctuation is observed and this has a significant effect on groundwater discharge to the sea when the landward boundary condition is a constant water level. The effect of beach slope is very significant and simplifying the problem by considering a vertical beach face causes serious errors in predicting the water‐table position and the groundwater flux. For media with a high effective capillary fringe, the moisture retained above the water table is important in determining the effects of the tidal fluctuations. Copyright © 2001 John Wiley & Sons, Ltd.     

山西静乐井水位异常调查与分析

山西静乐井水位从2007年7月以来,出现了第4次高值异常,但此次异常的特征与以往高值异常存在明显的差异。文章根据影响静乐井水位动态变化的主要因素,从井区环境、同层地下水开采情况及降雨三方面对静乐井水位第4次高值异常成因进行了调查与分析,明确了此次异常的性质。同时,根据静乐井对地壳应力一应变的响应能力及高值异常与地震活动的对应关系,给出了其对未来地震趋势的预测意义。     

Sea water intrusion by sea-level rise: scenarios for the 21st century

This study presents a method to assess the contributions of 21st-century sea-level rise and groundwater extraction to sea water intrusion in coastal aquifers. Sea water intrusion is represented by the landward advance of the 10,000 mg/L iso-salinity line, a concentration of dissolved salts that renders groundwater unsuitable for human use. A mathematical formulation of the resolution of sea water intrusion among its causes was quantified via numerical simulation under scenarios of change in groundwater extraction and sea-level rise in the 21st century. The developed method is illustrated with simulations of sea water intrusion in the Seaside Area sub-basin near the City of Monterey, California (USA), where predictions of mean sea-level rise through the early 21st century range from 0.10 to 0.90 m due to increasing global mean surface temperature. The modeling simulation was carried out with a state-of-the-art numerical model that accounts for the effects of salinity on groundwater density and can approximate hydrostratigraphic geometry closely. Simulations of sea water intrusion corresponding to various combinations of groundwater extraction and sea-level rise established that groundwater extraction is the predominant driver of sea water intrusion in the study aquifer. The method presented in this work is applicable to coastal aquifers under a variety of other scenarios of change not considered in this work. For example, one could resolve what changes in groundwater extraction and/or sea level would cause specified levels of groundwater salinization at strategic locations and times.     

Quantitative analysis of the driving factors for groundwater resource changes in arid irrigated areas

How to quantify the impact of climate change and human activities on groundwater is not only a hot topic of current research but also a key point of water resource management in arid irrigated areas. Therefore, this paper analyzes the changes in the trends of land use, climate, and groundwater extraction in the Yanqi Basin in recent years and uses the distributed hydrological model MIKE-SHE to quantitatively analyze the impacts of these three factors on groundwater resources. The results show that: 1. The Nash coefficients of the simulated and observed groundwater levels during the verification period are 0.84, 0.79 and 0.76; the correlation coefficient between the simulated and observed soil moisture is 0.86. Although there are some uncertainties in the simulation, the results prove that the model can be used to simulate arid irrigated areas. 2. The effects of these three factors on groundwater levels are 5, 12.5 and 82.5%, respectively, and have caused the regional average groundwater level to decrease by a maximum of 0.07, 0.23 and 1.79 m, respectively. The effects of these three factors on the interactions between surface water and groundwater were 7.04, 3.63 and 89.33%. Groundwater extraction has become the main influencing factor of regional groundwater resources changes due to its more direct influence. 3. The influence of groundwater extraction has a strong spatial distribution characteristic and 10% of the study area has been greatly impacted by the groundwater extraction. Base on the above results, integrating multidisciplinary knowledge to establish the relationship between ecological environment and groundwater changes can provide strategies for the sustainable development of groundwater.     

唐山马家沟矿井水位异常分析

地下水动态受水文因素影响较大,对地震和构造活动具有较灵敏的响应。判别并排除各种水文干扰,确认地下水在地震前的异常变化,对提高地震分析预报能力,具有重要作用。马家沟矿井水位动态观测层与地下水开采层为同一含水层,井水位于2010年出现破年变异常,加速持续上升,截至2015年,最大上升幅度约30 m。依据该井水文地质环境特征,根据唐山市区2001-2015年地下水位、降雨量、地下水开采量实测资料,建立合理多元回归模型和三维地下水流动模型,发现地下水开采量减少应为影响马家沟矿井水位动态的可能因素。文中采取的异常识别与分析方法,可为其他类似井孔的地下水动态异常识别及判定提供一定借鉴。     

Interaction of groundwater with Lake Urmia in Iran

Being a large hyper‐saline water body, Lake Urmia in north‐western Iran deals with a gradual decline in its water level. Most of the studies on Lake Urmia have neglected the groundwater issue. In this study, as a direct approach, the interaction between the groundwater level and the lake water level is investigated both in time and space by analysing the groundwater data compiled from observation wells surrounding the lake. Baseflow separation is considered as an indirect approach to understand the groundwater contribution to the river network flowing into the lake. It is determined that about 70% of run‐off in the rivers draining into the lake is born in the form of baseflow. An interaction between the lake and the groundwater storage is clearly seen from the analysis to conclude that groundwater has a potential to recharge the lake. Thus, the shrinkage of water level in Lake Urmia could be expected to accelerate with the drastic use of groundwater, which will be a disaster with no return.     

Evolution of Quaternary groundwater system in North China Plain

The Quaternary groundwater system in the North China Plain is formed mainly through the terrestrial water flow action on the united geological and tectonic backgrounds. The analysis of groundwater dynamic field, simulation of groundwater geochemistry, and the¹⁴C dating and extraction of isotope information have provided more evidence for recognizing and assessing the evolution of groundwater circulation system and studying the past global changes. The exploitation and utilization of groundwater on a large scale and overexploitation have given rise to the decline of regional groundwater level, change of flow field, decrease of water resources and downward movement of saline water body. The water environment has entered a new evolution stage in which it is intensely disturbed by the mankind’s activities. Project supported by the National Natural Science Foundation of China.     

中短期地震前兆的模糊综合识别

本文把模糊模式识别的直接方法用于综合分析多台多种手段观测到的地震前兆资料,以便提取较大地震前几个月内可能出现的中短期前兆异常信息。 所用方法的基本技巧是,对每一个台的每一种前兆观测手段建立起适当的前兆从属函数,并进而确定出多手段或多台的综合前兆从属函数。首先以综合前兆从属函数为基础,识别出某一地区较大地震前出现的中短期前兆异常,然后将其归纳成可用于地震预报的中短期前兆模式。 借助于所提出的方法,本文着重分析处理了1979——1986年间日本东海地区及其邻近地区3个倾斜台、2个验潮站、2个水氡观测站、2个水位观测点和30个体积应变观测点的大量前兆观测资料,识别出了这一期间在该地区内发生的10余次6级以上地震前的中短期前兆异常时间,并得出了两类地震前兆模式:第一类前兆模式适用于在该地区内进行多种前兆手段的综合分析预报;第二类前兆模式适用于单种前兆手段(体积应变)的多台综合分析预报。 为对比起见,文中同时给出了我国唐山7.8级地震及其6.9级强余震前多台水氡含量变化的中短期前兆综合分析识别结果,所得出的前兆模式与日本东海地区的第二类前兆模式相符。      

Explosive lava–water interactions II: self-organization processes among volcanic rootless eruption sites in the 1783–1784 Laki lava flow, Iceland

We have applied quantitative geospatial analyses to rootless eruption sites in the Hnúta and Hrossatungur groups of the 1783–1784 Laki lava flow to establish how patterns of spatial distribution can be used to obtain information about rootless cone emplacement processes and paleo-environments. This study utilizes sample-size-dependent nearest neighbor (NN) statistics and Voronoi tessellations to quantify the spatial distribution of rootless eruption sites and validate the use of statistical NN analysis as a remote sensing tool. Our results show that rootless eruption sites cluster in environments with abundant lava and water resources, but competition for limited groundwater in these clusters can cause rootless eruption sites to develop repelled distributions. This pattern of self-organization can be interpreted within the context of resource availability and depletion. Topography tends to concentrate lava (fuel) and water (coolant) within topographic lows, thereby promoting explosive lava–water interactions in these regions. Given an excess supply of lava within broad sheet lobes, rootless eruption sites withdraw groundwater from their surroundings until there is insufficient water to maintain analogs to explosive molten fuel–coolant interactions. Rootless eruption sites may be modeled as a network of water extraction wells that draw down the water table in their vicinity. Rootless eruptions at locations with insufficient groundwater may either fail to initiate or terminate before explosive activity has ceased at nearby locations with a greater supply of water, thus imparting a repelled distribution to observed rootless eruption sites.