关中南部地下热水氢氧 同位素组成的水文地质意义

通过对关中南部地下热水氢氧同位素组成研究,探讨了研究区地下热水的起源、补给以及有关净热水 的循环温度、循环深度、与冷水混合比例等与地下热水有关的热点问题,并与传统水文地质勘探方法进行了对比 研究。氢氧同位素研究结果表明,研究区地下热水为净热水与常温水的混合,常温水混合量达半数以上。根据 SiO2地热温标计算,净热水的热储温度为80℃～121℃,热储深度为1146.84～1779.38m。净热水的补给水源 平均气温与现代降水平均气温相差约16℃。净热水的来源为第四纪末次冰期秦岭海拔1800m以上的冰川 雪水。     

关中盆地地下热水接受补给时温度及热储层温度的估算

通过对关中盆地地热井中地下热水的同位素和水化学成分分析,结合研究区的地热地质和水文地质条件,进行了地下热水补给时的温度研究,结果表明,关中盆地地下热水接受补给时的温度以西安地区最低,咸阳次之。同时应用Na-K-Mg三角图和水化学平衡温度理论的方法,估算在平衡条件下关中盆地最大热储温度为118℃。热储温度计算结果表明,关中盆地腹部应为中低温热储层。     

The source of replenishment of geothermal water around Xi'an

The meteoric origin of the geothermal water in Xi'an is evidenced by its H and O isotope composition. Based on the temperature dependence of isotopic composition, the temperature of meteoric water that replenishes the geothermal aquifers in Xi'an and its neighboring regions is calculated to be −13.28°C. The age of the geothermal water based on¹⁴C dating method is 10–30 kaBP, belonging to a secondary glacial period in Late Quaternary. The source of replenishment is considered to have mainly derived from glacial snow melt water from elevations higher than 2,000m (ASL) in Qinling Mountains.

     

关中盆地地下热水环境同位素 分布及其水文地质意义

通过对关中盆地地下热水2H、18O、13C、14C、34S分布特征的研究,阐述了关中盆地腹部与其周边地区地下 热水环境同位素异同现象及其水文地质意义,论证了关中盆地地下热水的补给循环及其赋存环境特征。研究表 明:关中盆地地下热水中环境同位素δ(18O)、δ(D)、δ(13C)、δ(14C)、δ(34S)的分布除δ(D)外均呈现中部富集、周边 贫化趋势,指示关中盆地腹部咸阳及西安城区1500m以下地下热水赋存环境相对封闭;地下热水滞留时间较 长,以碳酸盐矿物溶解为主的水岩反应强烈,热储层中碳酸盐溶解对地热水中的HCO- 3、δ(18O)、δ(13C)随深度 增加趋势有明显贡献,δ(D)在盆地中部的贫化指示地下热水补给时的温度偏低,根据补给高程计算,西安、咸阳 城区地下热水分别为秦岭和北山末次冰期雪水补给。     

Oxygen and hydrogen isotope exchange of geopressured thermal water in the central Guanzhong basin

Geothermal water of Xi'an and Xianyang in the central Guanzhong basin is typically geopressured thermal water in China. δ18O and δD data of geopressured thermal water in Xi'an and Xianyang, combined with data from the perimeter of the basin, are analyzed to study features of hydrogen and oxygen shifts. The results show that 18O exchange of geothermal water at the pc-rimeter of the basin and in the non-geopressured thermal water in the center of the basin is not evident, while in most of the geo-pressured thermal water in the central basin, in cities such as Xi'an and Xianyang, significant oxygen exchange had taken place as well as hydrogen exchange, suggesting that isotope exchanges would slowly move the geothermal water system towards equilib-rium. Thermal water reservoirs in the central basin have passed through significant water-rock reactions. Moreover, the geothermal reservoir of Xianyang city is relatively much more enclosed than that of Xi'an city. It has been observed that the more enclosed the geological environment of geothermal water is, the more obvious the oxygen shifts are. With the increasing of the depth, residence time, total amounts of thssolute solids and temperatures of geothermal waters, the oxygen exchange accelerates.     

陕西关中盆地地热资源及壳幔温度结构的地球物理分析

陕西关中盆地地下热水资源丰富,是中国典型的隐伏型中、低温地热资源分布区。为研究关中盆地中、低温地热系统形成机理,认识深部热源条件,利用地球物理方法分析了该区壳幔温度结构。结果表明:计算得到的居里面平均深度为25.0 km,莫霍面平均深度为36.6 km,地壳平均地温梯度为22.60 ℃·km^-1,咸礼断阶、西安凹陷、固市凹陷地壳地温梯度高于平均值,是地热地质条件较好的构造分区。咸阳、西安之下,上地幔存在向南下倾的高温带,咸阳北侧约175 km深度是一个温度大于1 500 ℃的高温区; 其上,莫霍面、居里面上隆,形成高温基底,加热沉积地层中的地下水。富平、渭南之间,上地幔存在“下沉”低温区,低温区北、南两侧约175 km深度分别对应温度大于1 450 ℃的高温区; 高温区之上,莫霍面、居里面上隆,形成聚热中心,为地表地热资源提供稳定热源条件。总体上,关中盆地新生代潜水受莫霍面、居里面上隆带入的地幔热量传导加热,热物质随莫霍面、居里面向上抬升,是盆地中、低温地热田的深部热源。上地幔流变边界层控制研究区重要的构造活动,此边界层受周缘构造带不同动力作用,在重力均衡调整过程中,导致深大断裂活动,进而引起地壳深、浅部水体沿断裂带热对流,形成带状分布热泉。     

内蒙古河套平原水体同位素及水化学特征

运用环境同位素和水化学技术,结合现场调查和室内分析,分析了河套平原不同类型水体氢、氧同位素和水化学特征,讨论了不同水体受蒸发浓缩和人类活动的影响,并利用氢、氧同位素示踪地下水的补给来源。结果表明：河套平原大气降水线斜率小于全球大气降水线斜率,不同水体的氘过量参数小于包头地区大气降水线和全球大气降水线,反映水体的蒸发作用导致氢、氧同位素的富集;河水、湖水以及地下水的氢、氧同位素组成变化差异明显,而且从湖水到河水再到地下水,氢、氧同位素组成有逐渐贫化的趋势;不同水体的水化学类型明显不同,河水主要为HCO3-Ca型,地下水主要为HCO3-Na、HCO3-Ca以及Cl-Na型,湖水为SO4-Mg和Cl-Na型;地下水与河水的氢、氧同位素组成和各离子质量浓度的相关性差,湖水的氢、氧同位素组成与K＋、Ca2＋、Mg2＋、Na＋、Cl-、SO42＋质量浓度,pH值,电导率以及矿化度则存在显著的相关性;河套平原南侧与西部地区地下水主要靠黄河水补给,北侧主要受降水和山前流水的侧向补给,而东部靠近乌梁素海地区的地下水氢、氧同位素组成和矿化度偏高,可能受湖水的影响较大。     

山西断陷盆地榆次经纬厂一带地热水勘查及同位素地球化学特征

山西断陷盆地蕴藏着巨大的地热资源,榆次经纬厂-带位于该盆地中部.地热水资源非常丰富.应用CSAMT法进行探测显示新生代厚度约2500～2700m,钻探取样水化学分析矿化度极高,含盐度接近于海水.D、O同位紊分析表明比值接近雨水线,氚值很低,说明地热水补给源较远,交替更新的循环周期长,水流速迟缓,在含水层内储存时间较长,...     

云南曲靖市水资源保证程度和应急地下水源地分析

曲靖城区水资源主要源于大气降水,天然补给量有限,地表水系严重污染.水资源量保证程度总体能适应城市发展需要,但水质保证程度较低,供水安全脆弱性高.在环境水文地质调查的基础上,提出盆地东缘的岩溶地下水是优质的应急供水水源,笕槽坝和越州富水块段可作应急地下水源地.     

Studies of geothermal waters in Jiangxi Province using isotope techniques

Isotope hydrogeological studies of thermal waters conducted in the Lushan hotspring area, northern Jiangxi Province, the Maanping hotspring area, central Jiangxi, and the Henjing hotspring area, southern Jiangxi Province show that the local meteoric water line of Jiangxi Province is similar to the Craig line. The δD and δ¹⁸O values of geothermal waters in the province are roughly in accord with the local meteoric line, which implies that the thermal waters are of meteoric origin. Variations of isotopic composition of natural waters in the study areas reveal that the recharge areas of the geothermal fields are the adjacent mountains. The ages of geothermal waters measured by different dating methods, such as Ra/Rn dating and tritium dating, range from several decades to several hundred years in the Province which suggests that the geothermal waters are undergoing active circulation. The³He/⁴He ratios of gases from the hotsprings in the Hengjing hotspring area show that the hotspring gases originate from the depth, and probably partly from the mantle source.

     

遵化市汤泉地热资源综合评价

为了查明汤泉地区地热资源的分布范围,确定汤泉地区地热田的地热地质条件、热储层分布特征及导热和控热构造,开展了地面地质调查、高精度磁测、高精度重力勘探、井中温度测量、抽水试验、水质分析与同位素分析等工作,最终基本查明了汤泉地区地层岩性、地质构造、地下热流体的动力场、温度场和流体化学场特征,进而明确了该地区地热资源的分布范围.     

磁西煤系下岩溶热水水文地球化学特征及成因

根据水质分析结果,并结合岩溶地下水水质资料,分析了磁西煤田一号采区的深层岩溶热水水文地球化学特征、热储特征及其成因。结果表明,磁西煤田煤系下具有高TDS、高硬度、S04Cl-CaNa型水质特征的深层岩溶温热水是地下水沿断裂构造参与深部循环、长期演化的结果;地热异常属于热水型地热,热储温度可达60℃以上,循环深度在1500m以上,热源来自于燕山期岩浆侵入岩体产生的热异常与区域地温的叠加。本研究同时也为地热资源研究、煤田开发、矿井热害和矿井水防治提供有意义的参考。     

丹东海水入侵区域地下水同位素特征分析

丹东沿海地区海水入侵逐年加剧,入侵面积达到593km2。监测区域地下水和补给源同位素值,分析内陆地下水和入侵区地下水同位素特征,认为内陆地下水由大气降水补给,入侵区地下水受海水补给。结合化学法监测参数,分析入侵区地下水不同离子与同位素的相关关系,根据物质守恒原理,由相关系数R2的大小分析水岩反应,科学评价海水入侵的影响。     

Gas isotopes and geochemistry of hot springs in Hengjing,Jiangxi Province

With emphasis on gas isotopes and geochemistry as well as hydrogeochemistry, a field investigation has been carried out in Hengjing geothermal area, south Jiangxi Province of south-eastern China. The water chemistry of the geothermal waters indicates their local meteoric water origin, whereas their gas composition and carbon and helium isotopes reveal that some gases in the geothermal waters have mantle origin.     

河南省鹤壁市地热地质特征及开发前景

利用浅层水温统测、综合物探、钻探,基本查明了鹤壁新区地质构造、地温场及热储分布特征.发现了古近系、寒武—奥陶系热储均赋存有"热、医疗矿水、气体"三位一体的综合地热资源,古近系热储温度相对偏低,产量较小;寒武—奥陶系热储温度高,富水性极为不均,产量差异大.提出了综合利用及保护建议,开发井深宜控制在3500m以内,靠近古潜山北北东向断裂带寒武—奥陶系热储具有良好的开发前景,类似地区及下一步勘探开发具有参考价值.     

Isotope techniques for the research of groundwater in the potential site of China''''s high-level waste repository

Using the isotope techniques, the groundwater origin, evolution and circulation in the potential site of China's high-level waste repository are studied. The results indicate that both shallow groundwaters and deep groundwaters in the site area are of meteoric origin. The shallow groundwaters are mainly recharged by modern and local precipitation, and the deep groundwaters are originated from regional precipitation at higher elevation, or may be from the precipitation during the geological history period with lower temperature. Through the study we can also understand that the deep underground is a very low-permeability system where the groundwater flow-rates are very low.     

Isotope techniques for the research of groundwater in the potential site of China's high-level waste repository

Using the isotope techniques, the groundwater origin, evolution and circulation in the potential site of China's high-level waste repository are studied. The results indicate that both shallow groundwaters and deep groundwaters in the site area are of meteoric origin. The shallow groundwaters are mainly recharged by modern and local precipitation, and the deep groundwaters are originated from regional precipitation at higher elevation, or may be from the precipitation during the geological history period with lower temperature. Through the study we can also understand that the deep underground is a very low-permeability system where the groundwater flow-rates are very low.

     

贵州省铜仁地区地下热水的水化学特征研究

对铜仁地区地下热水的水化学特征进行了研究,得出以下结论:铜仁地区地下热水主要以低温地热水为主,水化学类型以HCO3- Ca、SO4- Ca和HCO3- SO4- Ca型为主.铜仁地区地下热水水质很好,绝大多数可以作用饮用水水源,部分水点可做为锶型矿泉水开发利用.铜仁地区地下热水化学成分是在地下水深循环中水岩相互作用的结...     

Gas isotopes and geochemistry of hot springs in Hengjing,Jiangxi Province

With emphasis on gas isotopes and geochemistry as well as hydrogeochemistry, a field investigation has been carried out in Hengjing geothermal area, south Jiangxi Province of south-eastern China. The water chemistry of the geothermal waters indicates their local meteoric water origin, whereas their gas composition and carbon and helium isotopes reveal that some gases in the geothermal waters have mantle origin.

     

汤水寨温泉带状热储特征及其热储量评价

汤水寨地热田出露处为大面积分布的花岗岩,且其深部的岩体完整,岩体渗透性差,故判断其为带状热储.据泉水及其附近雨水的氚含量检测,该泉水是由大气降雨所补给,泉水在地下的循环时间至少在10年以上.鉴于该带状热储层的体积较小,储水量及其热储量均十分有限,建议对其只进行小规模开发利用,仅利用其自流量作保健饮用或保健洗浴用水.