甘孜地区雅拉河段地热系统特征及控制因素

综合应用区域地质、地震、地球化学等资料,对甘孜地区雅拉河段地热系统及其主控因素进行研究。分析认为,甘孜地区地热属于典型的对流型地热系统,雅拉河断裂破碎带及板岩中发育的大量裂隙共同构成了研究区的热储体,这些热储体沿雅拉河断裂带不均匀分布。研究区充沛的大气降水以及季节性的冰雪融水为地热系统提供充足的水源。雅拉河断裂与色拉哈断裂之间大范围相对平坦的区域以及大量储水洼地为地热系统中的水源提供存储空间。该地区地表裂隙发育,利于地表水向下渗透,是地下水的主要补给通道。色拉哈断裂的强烈活动为浅层地下水在重力作用下进一步向深层运移提供重要流体通道。雅拉河断裂带的地势相对低,断裂破碎带是深层流体上涌的重要通道。在流体供给区与出露区的重力势能差以及两条走滑断裂带压力差共同作用下,流体经深部热源加热后在流体通道内形成持续的热流体循环系统。     

沧东断裂(天津段)特征及导水导热性质分析

沧东断裂是华北平原区一条规模较大的隐伏断裂,经历了中、新生代两个裂陷旋回,一直为地热地质工作者所关注。人工地震表明:沧东断裂是一空间构造形态上陡下缓、走向北东、北部边界已沿至蓟运河断裂附近的大型拆离断裂。以水文地质理论为基础,对沧东断裂附近地热流体的水化学场、温度场特征的研究表明:沧东断裂在下部并不具备控制天津地热热源的构造条件,但断裂上部却具有明显的将深部高位热能以热对流形式向浅部传导的特征;在水力传导方面,除局部地段稍弱外,总体上沧东断裂带在水平和垂直方向上有较强的导水能力。     

张掖盆地地热资源赋存特征及成因分析

张掖盆地地处甘肃省河西走廊黑河流域中游地区,地势南东高北西低。已有勘探资料显示,张掖盆地赋存丰富的水热型地热资源。通过研究该区域地球物理勘探、钻探、地温测量及水文地球化学等成果资料,分析了张掖盆地地热资源赋存特征,探讨了其成因模式。张掖盆地地热田属沉积盆地型中低温地热田,热储为呈层状分布的新近系白杨河组砂岩、砂砾岩,选择钾镁地球化学温标计算热储温度为47～82°C,盖层为新近系上新统疏勒河组泥岩及第四系松散地层;地热水类型主要为碎屑岩类孔隙水,根据氢氧同位素特征推断其主要补给来源为南部祁连山区大气降水;祁连山北缘深大断裂和盆地内NNW向基底断裂是地热流体深循环良好的导水通道,地下水接受补给后沿导水断裂带或岩层孔隙裂隙运移,在深部热传导的增温作用下,赋存于碎屑岩类孔隙之中形成了本区的地热资源。水质分析结果表明：本区地热水属于溶滤型的陆相沉积水,水化学类型为Cl·SO₄—Na型,F-、SiO₂、溶解性总固体、总硬度含量随水温的升高而增大;区内地热水3H值普遍小于2.0 TU,说明形成年代较早;¹⁴C分析结果进一步证实,区域地...     

聊城市城区地热地质特征与地热资源开发利用

山东省聊城市历史悠久,地热资源丰富,并含大量对人体有益的组份或离子。通过分析地热地质特征、地热水质特征、地热可采资源量,探讨聊考断裂与聊城市城区地热水类型、水温、有益组份或离子的关系,揭示了聊城市城区地热资源开发利用前景及科学、合理地综合开发利用地热资源。     

山东德州凹陷地下热水地球化学特征及成因

典型地区地下水成因和演化机制的研究不仅对于热水资源的合理利用与开发具有重要的指导意义,而且可以为日后的地热资源勘查评价提供重要信息。笔者通过对德州凹陷的地下热水的化学成分、同位素及其水文地质特征的分析,进而对这一地区的地下热水的成岩和演化过程进行了研究。结果显示地下热水的形成受区内深大断裂和基底构造对地热形成的控制,地下热水补给是来自大气降水,为入渗变质水,水化学成分以易溶盐溶解作用为主,其气体组分主要起源于大气、地壳和地幔的混合物,反映了地下水长期径流及深循环中各种水化学作用。     

The geothermal formation mechanism in the Gonghe Basin: Discussion and analysis from the geological background

The Gonghe Basin, a Cenozoic down-warped basin, is located in the northeastern part of the Qinghai-Xizang (Tibetan) Plateau, and spread over important nodes of the transfer of multiple blocks in the central orogenic belt in the NWW direction. It is also called “Qin Kun Fork” and “Gonghe Gap”. The basin has a high heat flow value and obvious thermal anomaly. The geothermal resources are mainly hot dry rock and underground hot water. In recent years, the mechanism of geothermal formation within the basin has been controversial. On the basis of understanding the knowledge of predecessors, this paper proposes the geothermal formation mechanism of the “heat source–heat transfer–heat reservoir and caprock–thermal system” of the Gonghe Basin from the perspective of a geological background through data integration-integrated research-expert, discussion-graph, compilation-field verification and other processes: (1) Heat source: geophysical exploration and radioisotope calculations show that the heat source of heat in the basin has both the contribution of mantle and the participation of the earth’s crust, but mainly the contribution of the deep mantle. (2) Heat transfer: The petrological properties of the basin and the exposed structure position of the surface hot springs show that one transfer mode is the material of the mantle source upwells and invades from the bottom, directly injecting heat; the other is that the deep fault conducts the deep heat of the basin to the middle and lower parts of the earth’s crust, then the secondary fracture transfers the heat to the shallow part. (3) Heat reservoir and caprock: First, the convective strip-shaped heat reservoir exposed by the hot springs on the peripheral fault zone of the basin; second, the underlying hot dry rock layered heat reservoir and the upper new generation heat reservoir and caprock in the basin revealed by drilling data. (4) Thermal system: Based on the characteristics of the “heat source-heat transfer-heat reservoir and caprock”, it is preliminarily believed that the Gonghe Basin belongs to the non-magmatic heat source hydrothermal geothermal system (type II2₁) and the dry heat geothermal system (type II2₂). Its favorable structural position and special geological evolutionary history have given birth to a unique environment for the formation of the geothermal system. There may be a cumulative effect of heat accumulation in the eastern part of the basin, which is expected to become a favorable exploration area for hot dry rocks.     

Br/Cl ratio,Zn and radon constraints on the origin and fate of geothermal fluids in the coastal region of southeastern China

Low-to-medium temperature geothermal fluids in the granite regions of southeastern China are an important renewable energy resource, but they are also a source of contamination containing highly toxic elements such as fluoride and arsenic. This study analyzed the origin of the geothermal fluids in a regional-scale hydrogeological unit in the city of Xiamen, China, based on isotope and hydrochemical analyses. The Br/Cl ratios suggested that the inland geothermal fluid is merely recharged by rainwater from the mountain edge, while the coastal geothermal fluid is originally recharged by the seawater and later mixed with rain-derived groundwater. The geothermal water featured high SiO₂ and detectable Zn concentrations. The former reflects the significant water–granite interaction along the flow path, and the latter indicates the active hydraulic connection between surface waters, shallow aquifers and deep geothermal fluids. High radon content was detected near the deep conductive fault adjacent to a geothermal well, demonstrating that the fault damage zone acts as a major conduit for upward transport of the deep geothermal fluid. As a result, the fault damage zones developed in the granite are necessary for the formation of geothermal water, which leads to the uneven distribution of geothermal water in the subsurface. High-temperature geothermal water can be found in those regions with fairly sparse fault damage zones. In contrast, in the region with high-density fault activities, the active communication between shallow cool water and deep geothermal fluids can decrease the water temperature.

     

Geophysical evidence on segmentation of the Tancheng-Lujiang fault and its implications on the lithosphere evolution in East China

The north–south trending Tancheng-Lujiang (Tanlu) fault belt extends from northeast China to the Dabie–Sulu orogenic belt, for a length of more than 3000 km. This fault belt probably has close links with the lithosphere evolution, seismic activity and mineral resource concentration in East China. Surface geological mapping and studies on sedimentation and basin formation have indicated segmentation at the southern, middle and northern domains of the fault. Here we employ geophysical constraints to evaluate these fault segments. Unlike previous geophysical studies focused on laterally varying crust/mantle seismic velocity structure across the fault, in this study we have integrated a variety of geophysical data sets, such as crustal P-wave velocity, earthquake occurrence and released seismic energy, seismogenic layer thickness, surface heat flow and geothermal field, to understand the deep structure and strength of the lithosphere along the Tanlu segmented fault belt. The results demonstrate remarkable crustal-scale north-to-south segmentation this major fault. The geophysical evidence and some geochemical constraints suggest that the Tanlu fault belt probably served as a channel for melt and fluid percolation, and exerted a significant control on the lithosphere evolution in East China.     

鲁西平原地热水的化学特征及开发利用

鲁西平原地热水资源较丰富,属中低温地热,埋藏分布广,温度适中,开采潜力大。通过对鲁西平原地热水的水化学和冷水、海水的水化学进行对比分析,研究地热水的形成及水化学特征,根据地热水的水化学特征对地热水进行有针对性地开发利用。     

沂沭断裂带西缘昌乐县中部地区地热成热地质条件分析

通过对地质资料的分析,认为该区理论上具有较好的地热生成环境和赋存条件。重点围绕郎邵-葛沟断裂两侧,综合运用地质调查、测温、物探、钻探等手段,对成热地质条件进行调查分析,圈定淳于地热异常区和梁家庄地热异常区2个异常区,分析并初步确定热源为地壳深部的热流,导水导热通道为部邵-葛沟断裂及其次级断裂,热储为深循环对流型带状热储,热储岩性为白垩纪青山群安山岩,埋深1400-2000m,盖层为新近纪、古近纪及白垩纪粘土岩、砂岩等。结合区域地质资料,建立地热资源概念模型,并据此确定了3处拟井位置及孔深。     

胶东半岛不同构造单元深部热流分流聚热模式

中生代、新生代时期地壳剧烈运动将胶东半岛划分为胶北隆起、胶莱凹陷、胶南-威海隆起三大构造单元,其中隆起山地区广泛分布花岗岩、变质岩,凹陷盆地区主要分布砂岩沉积地层,胶北隆起区与威海隆起区相对于胶莱凹陷盆地区具有更高的大地热流值.为系统分析胶东半岛大地热流值分布特征及其形成机理,本文在分析胶东半岛构造-热发展史、地热地质...     

西藏羊八井地热田水热蚀变的时空演化特征

西藏亚东—谷露裂谷中—北段的羊八井地热田是我国著名的高温地热田,研究其水热蚀变的时空演化有助于更好地认识藏南地热的发育特征。通过对羊八井地热田及其水热蚀变岩开展地表调查、显微特征与X衍射分析等工作,总结了其主要蚀变类型特征,划分出黄褐色蚀变中心带、灰白色中强蚀变带、灰白色中等蚀变带和浅灰白色弱蚀变带4个不同的水热蚀变带,并区分出红褐色—黄褐色蚀变期、灰白色蚀变期和淡黄色—灰色蚀变期共3期蚀变。研究结果揭示,羊八井地热田高温地热活动中心一直在北区硫磺沟区域,其水热蚀变活动主要受亚东—谷露裂谷内部的活动断裂构造控制,并与断裂构造活动具同步性;地热水的排泄方式早期为沿北东向断裂构造直接排泄,晚期为经浅层第四系径流后再排泄,由直接排泄向间接排泄转变;中高温地热水的排泄区由北区硫磺沟地区向南区藏布曲迁移。根据研究结果推断,硫磺沟区域的北东向断裂与北西向断裂交汇区可作为羊八井热田北区深部地热勘查的主要方向。     

南海东北部珠江口盆地成生演化与油气运聚成藏规律

珠江口盆地处在南海东北部准被动大陆边缘的特殊大地构造位置,其区域背景及油气地质条件复杂。该区不仅具有中国东部新生代陆相断陷盆地的基本特征,亦具本身的特殊性。由于盆地不同区带油气地质条件的差异,故具有明显的"北油南气"分布规律及纵向上多种资源叠置共生与复合的特点:北部裂陷带及东沙隆起浅水区,处于减薄的洋陆过渡型地壳靠近陆缘一侧,其古近系断陷规模及半地堑洼陷沉积充填规模均比相邻的南部裂陷带深水区小,且地温梯度低、大地热流小,烃源岩有机质热演化处在油窗范围,以产大量石油为主伴有少量油型气,构成了以文昌、恩平、西江、惠州及陆丰油田群和流花油田群为主的北部浅水油气富集区。该区具有上渐新统三角洲砂岩及中新统礁灰岩外源型油气运聚成藏机制及含油气系统;南部裂陷带及南部隆起周缘深水区,以邻近深水区的白云凹陷北坡—番禺低隆起中小气田群和白云凹陷东部深水区LW3-1、LH34-2及LH29-1等天然气藏为代表,构成了以天然气为主但亦具石油及水合物资源潜力的深水油气富集区。由于南部裂陷带深水区处在洋陆过渡型地壳靠近洋壳一侧,地壳薄而裂陷深、断陷规模大,其与北部浅水区相比多了一套上渐新统海相烃源岩。该区地温梯度及大地热流偏高,烃源岩多处在成熟-高熟凝析油及湿气阶段,以产大量天然气及少量轻质油和凝析油为主,具有上渐新统陆架边缘三角洲砂岩和中新统深水扇混源型天然气运聚成藏机制及含油气系统。油气纵向分布具有深水海底天然气水合物及浅层气/生物气与深部常规油气共生叠置的关系。     

太行山-雄安新区蓟县系含水层水文地球化学特征及意义

雄安新区蓟县系雾迷山组热储层中具有丰富的中低温地热资源,研究其地热流体水文地球化学特征可分析地热资源的形成机制,对推动雄安新区深部地热资源有效开发利用具有重要意义.太行山区雾迷山组为基岩裸露区,雄安新区雾迷山组基底埋藏较深,两个系统的地热流体经历不同的水岩相互作用,导致水化学特征有一定差异.通过对保定以西太行山区-雄安新区共26组蓟县系雾迷山组地热流体样品的水化学及同位素数据进行分析,研究地热流体的补给来源及经历的深部地热循环过程.太行山区雾迷山组流体水化学类型以HCO₃-Ca·Mg型为主,雄安新区以Cl·HCO₃-Na型为主.地热流体均来源于大气降水,通过断裂、裂隙等通道入渗,在长距离运移过程中伴随有矿物的沉淀和溶解现象,水岩相互作用逐渐增强.深部热循环深度为2 880.26~4 143.42 m,均值为3 700 m,深部热储温度为160℃左右;地热流体在深部通过断裂上升过程中,由于传导冷却、冷水混入及深部热源通过结晶基底的热传导作用,在750~2 100 m的凸起处雾迷山组碳酸盐岩地层中封闭聚集形成热储层,热储平均温度为70℃左右,属于对流-传导型地热系统.      

江西吉安钱山地区地热资源特征及热源机制

位于罗霄山脉北支武功山西南地区的钱山地热田是研究武功山地热资源的关键地区。本文综合区域地质、研究区地质特征、热物性参数、水化学特征、锆石同位素等方法, 重点分析了钱山地区的地热系统特征, 深入研究了钱山地热的构造背景和热源机制。研究表明: ①NE–SW向的和平—三江断裂是钱山地热重要的导热和控热构造; ②水化学及同位素特征指示钱山地区的地热水和冷水均为大气降水补给; ③早志留世黑云二长花岗岩热导率特征表明花岗岩具有很好的导热效果和聚热能力; ④黑云二长花岗岩放射性生热率较低且时代久远, 揭示放射性元素生热和岩浆岩余热对热源做出的贡献非常小, 钱山地热的热源主要来自壳源深部地热。本研究可为武功山地区地热资源成因及合理开发利用等提供重要的启示。     

山东省菏泽凸起地热田岩溶地热水水化学水平演化特征

在前人研究成果的基础上,选择A-A'和B-B'两条路径,采用Piper三线图解、Schoeller图解、Na-K-Mg平衡图解、饱和指数计算评价等方法,研究山东菏泽凸起地热田地热水沿路径上的循环演化特征.结果表明:沿A-A'、B-B'剖面岩溶冷水→岩溶热水,水化学类型由SO4?HCO3-Ca?Mg?Na或SO4?HCO...     

Geological characteristics and analysis of hydrothermal genesis in the Suijiang-1 well in Yunnan Province,China

The geothermal water hydrochemistry and isotopic characteristics of boreholes in the Suijiang-1 well in Yunnan Province were studied based on the actual drilling geology, regional geological structure and hydrogeological conditions. The analysis results show that the geothermal water is SO_4-Ca·Mg type, the recharge elevation is 1 381-1 646 m, the recharge source is atmospheric precipitation, the geothermal reservoir temperature is 42-45 ℃, and the geothermal water is controlled by lithology and geological structure conditions of study area. Atmospheric precipitation enters the groundwater circulation system through the surface karst form of the Wujiaobao anticline, northwest-southeast tensile faults, fissures and karst depression, and geothermal water formed through the rising deep cycle water temperature, then blocked by the double rivers' fault zone and drilling explosion.     

Geological characteristics and analysis of hydrothermal genesis in the Suijiang-1 well in Yunnan Province,China

The geothermal water hydrochemistry and isotopic characteristics of boreholes in the Suijiang-1 well in Yunnan Province were studied based on the actual drilling geology, regional geological structure and hydrogeological conditions. The analysis results show that the geothermal water is SO4-Ca?Mg type, the recharge elevation is 1 381-1 646 m, the recharge source is atmospheric precipitation, the geothermal reservoir temperature is 42-45 ℃, and the geothermal water is controlled by lithology and geological structure conditions of study area. Atmospheric precipitation enters the groundwater circulation system through the surface karst form of the Wujiaobao anticline, northwest-southeast tensile faults, fissures and karst depression, and geothermal water formed through the rising deep cycle water temperature, then blocked by the double rivers’ fault zone and drilling explosion.     

岸上襄郏断层中段地热地质特征

通过对岸上襄郏断层的地热地质条件分析,表明该断层在研究区可分为三部分,且以南部地热异常最为明显;热储盖层为其上覆二叠系含煤地层和第四系砂泥岩,主要热储层为寒武系固山组白云质灰岩;热水的水质类型为HCO3SO4—NaCa,大气降水是热水的主要来源,地下热水的垂直运移是形成热水主要原因。根据注水试验资料评价了断层带的地热资源量,按照地热资源利用率为15%,初步估算了断层带地热资源量为2 491.735万t标准煤,认为采用注采结合的方法开采地热资源是较为合理的。最后建议加强中部地区地热资源的进一步勘查研究,以获得更多的地热资源。     

山东菏泽地区地热田地质特征

菏泽地热田内蕴藏着丰富的地热资源,地质构造条件、热储地质条件都比较有利,是开发地热资源的有利地段。区域地质构造主要为聊考断裂和曹县断裂,热储层分2大类呈双层结构,上部为新近系孔隙-裂隙热储,下部为奥陶系碳酸盐岩裂隙岩溶热储。该区地下热水是50年前形成的,水中氟、偏硅酸达到矿水命名浓度,为氟水、硅水;锶已接近锶水;偏硼酸已接近矿水浓度,还含有F^-,H2SiO3,HBO2,Li等多种对人体有益的矿物元素,可作为采暖,洗浴等用水。