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本文讨论了在兼有传导和垂直对流两种传热作用下,一维稳态温度场所具有的特征和利用钻孔温度测量结果判别地下水对流存在与否及定量评定地下水活动对地温场影响的方法。以新郑矿区热异常区的一热水孔为例进行剖析,检验了方法的有效性。这一实例提供了确定新郑地热异常成因的重要基础。 相似文献
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在系统分析淮南煤田大量地面钻孔井温测井数据和井下巷道围岩温度测试数据的基础上,结合58块岩石样品的热导率测试结果,全面阐述了该区现今地温梯度和大地热流的分布特征。研究表明,淮南煤田现今地温梯度的众值介于2.50~3.50℃/hm之间,平均地温梯度为2.9℃/hm;大地热流值变化范围为31.87~83.9 m W/m2,平均热流值为63.69 m W/m2,地温梯度和热流值区均高于淮北煤田;大地热流受地温梯度控制明显,其变化特征和地温梯度分布较为相似,整体表现为中东部高,西部其次,东南部最小的特征。分析揭示,区内现今地温场和热流分布主要受区域地质背景和区内构造格局的控制。 相似文献
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本文在大量钻孔测温资料的基础上,系统分析了河南省城市浅层地温场分布特征,分析了不同地貌类型城市恒温带特征。全区地下水恒温带深度平均深度24.8m,温度一般15.5℃~17.5℃;冲积平原区松散层恒温带深度最浅、温度最高,内陆河谷盆地区松散层恒温带深度最深、温度最低。近山前地带基岩浅埋区,地温梯度低;沿深大断裂带和构造隆(凸)起区,地温梯度高;济源—商丘断裂的新乡—延津段、内黄凸起和通许凸起地温梯度高。通过分析地温增温率特征和地温恢复能力,得出颗粒越粗地温恢复能力K值较大,富水性越强、水力坡度越大K值越大。对影响浅层地温场的多种因素的系统研究表明,该区浅层地温场受城市、人类活动、地下水流场、地下水埋深、构造、地下水补给、排泄等因素影响明显。 相似文献
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顺和西煤矿区地温特征及其影响因素分析 总被引：1，自引：0，他引：1
顺和西煤矿区属华北地台型含煤沉积、石炭、二叠系为其主要含煤地层,山西组的二：煤层为主采煤层,埋深585～1585m。由于永城隐伏背斜两翼发育的次级宽缓褶曲及其高角度断层,控制着本区含煤地层的分布,故该矿区的地温亦受各种地质因素的作用与控制,表现为同一水平地层越老温度越高,背斜轴部地温和增温率均高于向斜轴部;中北部地温梯度较高,增温异常;南部、东北局部地温梯度较低,增温正常;地温梯度随深度的增加而减小,并在岩浆侵入地段与非侵入地段也有明显差异。地温随深度或煤层埋深的增大而增高。二：煤层除局部较浅地段为一级热害区外,二级热害区基本覆盖全区。 相似文献
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汤泉位于河北省遵化市西北部,为山前丘陵地貌,地热资源丰富。本文对汤泉地热田内分布的诸多基岩热水井进行了钻孔测温,利用测温结果对该地热田地温场分布特征及控制因素进行了研究。研究发现:钻孔温度明显受地下水流的影响,绝大部分测温井表现为对流传热特征,个别表现为传导为主的传热特征;地温异常区域位于汤泉福泉宫和疗养院一带,异常中心呈两极分布,地热异常中心50 m埋深水温为51~54℃,100 m埋深水温可达60~67℃;该地热系统中地热水系地下水在深循环过程中,在正常的大地热流背景下被围岩逐渐加热所致;由花岗岩隔水底板构造形态所形成的隐伏盆地,构成了福泉宫至疗养院一带的蓄水构造;由于断裂构造切割花岗岩体,造成深部的热流沿断裂上升,混合并加热赋存于福泉宫至疗养院一带蓄水构造中的片麻岩裂隙水,形成该地段的地热异常现象;福泉宫地区和疗养院地区片麻岩含水层裂隙发育,使得深部热量能够快速到达浅部地层,并在浅部出现局部异常高温;汤泉地热田片麻岩热储层地热流体属于含岩盐地层溶滤的陆相沉积水,主要来源于大气降水。 相似文献
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淮北煤田的高温热害问题愈发突出,但目前对该区系统的地温场特征及大地热流分布研究非常稀少.在系统分析淮北煤田大量地面钻孔井温测井数据和井下巷道围岩温度测试数据的基础上,结合72块岩石样品的热导率测试结果,全面阐述了该区现今地温梯度和大地热流的分布特征.研究表明:淮北煤田现今地温梯度众值介于1.80~2.80 ℃/100 m之间,平均地温梯度为2.42 ℃/100 m;大地热流值变化范围为39.52~74.12 mW/m2,平均热流值为55.72 mW/m2,地温梯度和热流值均低于同处华北板块的其他盆地以及南部的淮南煤田;大地热流受地温梯度控制明显,两者分布较为相似,整体表现为南高北低、西高东低的特点.结果表明,区内现今地温场和热流分布主要受区域地质背景和区内构造格局的控制. 相似文献
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平顶山十三矿位于断块构造的凸起部位,矿井地温场与基底起伏有密切关系,地温异常的形成和地温场的变化是地壳深部的均匀热流上升至浅部时,因构造造成的岩石热导率侧向差异而形成的,是不均一传导传递的结果。梁北一井田地温场变化特点则与地下水对热量的对流传递有关,在岩溶较发育、承压水上升活动强烈的构造部位,地温梯度增高,形成地温异常.按照起决定作用的热传递方式划分矿山地温类型,前者属传导型地温场,后者属对流型地温场。 相似文献
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地温测量是研究地温场分布最直接的方法。地热热源的强度与分布,直接影响地壳表层土壤温度场的分布,特别是存在热储层、热运移通道等都会使地温场的分布产生异常。在研究区16个民井和32个钻孔中进行地温测量,分析地温场分布状况以及地下热水活动规律,效果明显。结果表明研究区浅孔与深孔地温场平面特征一致,越接近东北角地温越有增加的趋势,而且地温异常区呈NNE向条带状分布,宽度约700 m,与NNE向断裂展布方向一致,地温最高点位于NW向断裂与NNE向断裂交汇处。研究区在纵向上地温分布特征差异性明显,地下热水分布范围较小,具有一定局限性,主要受构造断裂、岩溶发育程度等控制,温度低的地下水大量涌入导致地下水温降低,地温梯度出现异常;这种地温梯度异常现象也说明了研究区地下热水主要储存于灰质白云岩或角砾岩的裂隙溶洞中,裂隙、岩溶成为地下热水良好的运移通道。地温测量方法圈定了研究区地热异常区范围,为进一步勘查地热提供了重要的依据。 相似文献
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基于黔西补作勘查区32口钻孔的简易测温资料,分析了勘查区浅部地温场的基本特征。研究发现,区内地温梯度在0.98～3.25℃/100m,平均2.07℃/100m,总体上属于正常地温场范畴;平面上变化较大,局部存在低温异常,在垂向上随着孔底深度增大,各钻孔地温梯度总体上趋于增高,但与埋深之间关系相对离散,钻孔温度曲线表现为两种基本形式。研究认为,断层构造控制了地温场的分布,地温异常带的展布方向反映区域构造的基本轮廓;地下水动力场微弱,对地温场影响不甚明显;地层岩性及埋深影响地温场的垂向分布。 相似文献
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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、地热地质背景、地温场分布、岩石热导率、钻孔岩性与测温数据、地热流体化学成分等基础上,发现胶东半岛地热资源均为断裂构造控制类型的中低温对流型,其热源主要为三元聚热:导热断裂带水热对流、大地热流传导、地下水运移传导-对流;构造分布、岩石热物性、地热热储分布、地下水活动等是影响地温场分布的主要因素.针对胶东半岛地温场特征及其控制因素,提出了适合该地区的隆起-凹陷分流聚热模式与概念模型,即隆起山地区岩性以导热率、渗透率相对较高的侵入岩、变质岩为主,凹陷盆地区岩性以导热率、渗透率相对较低的砂岩为主,低导热率、低渗透率的凹陷区底部更像是一个相对隔热、隔水的顶板,使得来自地壳深部的大地热流及携带热量的流体、气体等在上涌的过程中在凹陷区的底部发生折射与再分配,从而导致热流在隆起山地区的底部形成一个温度相对更高的聚热区,反映在地表即是隆起山地区相对凹陷盆地区具有更高的大地热流值,特别隆起山地区轴部位置为热流值最高的区域,高热流值区域分布形态呈NE、NNE向分布,基本与胶东半岛NE、NNE向的深大断裂走向一致,该模式的提出可以更好地为胶东地区的地热资源勘探提供指导方向. 相似文献
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地温场是采矿活动的重要地质条件之一。基于332井次钻孔测温数据、地层岩性及其组合特征、构造地质及水文地质条件等,探讨了寺家庄井田地温负异常及其主控因素。结果表明:寺家庄井田现代地温场受地层及热导率、地下水和开放型构造等三大地质因素控制。地层砂岩所占比例较高,其导热性强、热传导快,不易造成局部聚热,是井田地温值整体偏低的主要控制因素,区域地下水的强径流状态是现代地温整体偏低的宏观控制因素;地下水径流状态对围岩温度起到"制冷"和诱发构造通道散失双重控制作用,是研究区地温负异常和地温场分异的重要控制因素,开放型张性较大正断层、陷落柱不但为地温的散失提供了有利通道,亦为邻近含水层间地下水循环、径流对围岩温度的"制冷"提供了有利条件,是井田地温负异常和地温场分异的关键控制因素。 相似文献
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There are many arguments on energy sources and main controlling factors of geothermal fields, so a systematic study on the distribution of ground temperature fields shall be necessary. In this paper the thermal conduction forward method of geothermal field is used to simulate cooling rate of abnormal heat sources and heat transfer of the paleo-uplift model. Combined with a large number of geothermal field exploration cases and oil exploration well temperature curves of domestic and foreign, the following conclusions are drawn: (1) According to the magmatic activity time, the magmatism activities are divided into two categories: Magma active areas (activity time < 500 000 years) and weak/magma inactive areas (activity time > 500 000 years). The latter has a fast cooling rate (the cooling time of the magma pocket buried around 10 km is less than 200 000 years) after it has intruded into the shallow layer and it has no direct contribution to modern geothermal fields; (2) China belongs to a weak/magma inactive area such as Tengchong region and Qinghai-Tibet region because the chronological data of these regions show that its magma activity time is more than 500 000 years; (3) The temperature of most geothermal fields can be obviously divided into three segments in the vertical direction: A high geothermal gradient segment (Segment H) at the surface, then a low geothermal gradient segment (Segment L) at a secondary depth, and finally a lower temperature segment (Segment D) at a deeper depth. The temperature isoline presents a mirror reflection relation on the temperature profile, indicating that geothermal field is dominated by heat conduction, rather than having an abnormally high temperature “heat source” to provide heat; (4) Near-surface (0-5 km) materials’ lateral heterogeneity caused by tectonic movement shall probably be the main controlling factor of ground temperature fields. 相似文献
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There are many arguments on energy sources and main controlling factors of geothermal fields, so a systematic study on the distribution of ground temperature fields shall be necessary. In this paper the thermal conduction forward method of geothermal field is used to simulate cooling rate of abnormal heat sources and heat transfer of the paleo-uplift model. Combined with a large number of geothermal field exploration cases and oil exploration well temperature curves of domestic and foreign, the following conclusions are drawn:(1) According to the magmatic activity time, the magmatism activities are divided into two categories: Magma active areas(activity time 500 000 years) and weak/magma inactive areas(activity time 500 000 years). The latter has a fast cooling rate(the cooling time of the magma pocket buried around 10 km is less than 200 000 years) after it has intruded into the shallow layer and it has no direct contribution to modern geothermal fields;(2) China belongs to a weak/magma inactive area such as Tengchong region and Qinghai-Tibet region because the chronological data of these regions show that its magma activity time is more than 500 000 years;(3) The temperature of most geothermal fields can be obviously divided into three segments in the vertical direction: A high geothermal gradient segment(Segment H) at the surface, then a low geothermal gradient segment(Segment L) at a secondary depth, and finally a lower temperature segment(Segment D) at a deeper depth. The temperature isoline presents a mirror reflection relation on the temperature profile, indicating that geothermal field is dominated by heat conduction, rather than having an abnormally high temperature "heat source" to provide heat;(4) Near-surface(0-5 km) materials' lateral heterogeneity caused by tectonic movement shall probably be the main controlling factor of ground temperature fields. 相似文献
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Heather A. Sheldon Brendan Florio Michael G. Trefry Lynn B. Reid Ludovic P. Ricard K. Ameed R. Ghori 《Hydrogeology Journal》2012,20(7):1251-1268
Convection of groundwater in aquifers can create areas of anomalously high temperature at shallow depths which could be exploited for geothermal energy. Temperature measurements in the Perth Basin (Western Australia) reveal thermal patterns that are consistent with convection in the Yarragadee Aquifer. This observation is supported by Rayleigh number calculations, which show that convection is possible within the range of aquifer thickness, geothermal gradient, salinity gradient and permeability encountered in the Yarragadee Aquifer, assuming that the aquifer can be treated as a homogeneous anisotropic layer. Numerical simulations of convection in a simplified model of the Yarragadee Aquifer show that: (1) the spacing of convective upwellings can be predicted from aquifer thickness and permeability anisotropy; (2) convective upwellings may be circular or elongate in plan view; (3) convective upwellings create significant temperature enhancements relative to the conductive profile; (4) convective flow rates are similar to regional groundwater flow rates; and (5) convection homogenises salinity within the aquifer. Further work is required to constrain the average horizontal and vertical permeability of the Yarragadee Aquifer, to assess the validity of treating the aquifer as a homogeneous anisotropic layer, and to determine the impact of realistic aquifer geometry and advection on convection. 相似文献
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Arianna Bucci Diego Barbero Manuela Lasagna M. Gabriella Forno Domenico Antonio De Luca 《Environmental Earth Sciences》2017,76(5):221
This study investigated the thermal regime of shallow groundwater in the Turin area (NW Italy), where the large energy demand has motivated a new interest for renewable sources, such as the use of ground-source heat pumps for domestic heating and cooling. The vertical variability of the groundwater temperature between the ground surface and 10–20 m was detected: deeper temperatures were higher than shallow temperatures in spring, while a decrease with depth occurred in autumn. These variations are connected with the heating and cooling cycles of the ground surface due to the seasonal temperature oscillation. Variations below the seasonal oscillation are likely to be connected with the presence of advective heat transport due to the groundwater flow, according to the hydraulic features of a shallow aquifer. Temperature values mostly ranged between 12 and 14 °C in rural areas, while the values were between 14 and 16 °C below the Turin city. This groundwater warming is attributed to a widespread urban heat island phenomenon linked to warmer land surface temperatures in Turin city. Sparse warm outliers are connected with point heat sources and site-specific conditions of land and subsurface use, which may cause the aquifer temperature to rise. A relatively stable temperature below the seasonal fluctuation zone combined with high productivity and legislated limits for deeper groundwater use represent favourable conditions for a large-scale diffusion of groundwater heat pumps within the shallow aquifer. Moreover, this heat surplus should be regarded as a resource for future geothermal installations. 相似文献
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In porous sediments of the Ishikari Lowland, there is a gradual increase in the background geothermal gradient from the Ishikari
River (3–4 °C 100 m–1) to the southwest highland area (10 °C 100 m–1). However, the geothermal gradient at shallow depths differs in detail from the background distribution. In spite of convective
heat-flow loss generally associated with groundwater flow, heat flow remains high (100 mW m–2) in the recharge area in the southwestern part of the Ishikari basin, which is part of an active geothermal field. In the
northeastern part of the lowland, heat flow locally reaches 140 mW m–2, probably due to upward water flow from the deep geothermal field. Between the two areas the heat flow is much lower. To
examine the role of hydraulic flow in the distortion of the isotherms in this area, thermal gradient vs. temperature analyses
were made, and they helped to define the major components of the groundwater-flow system of the region. Two-dimensional simulation
modeling aided in understanding not only the cause of horizontal heat-flow variations in this field but also the contrast
between thermal properties of shallow and deep groundwater reservoirs.
Electronic Publication 相似文献
19.
S. Bachu 《Tectonophysics》1985,120(3-4):257-284
A detailed study of the groundwater and terrestrial heat flow was carried out over an area of 23,700 km2 west of Cold Lake, Alberta, which is part of the western Canada sedimentary basin. The information for the study was provided from data from 3100 wells drilled in the area. The screening and processing of thousands of stratigraphic picks, drillstem test data, bottom hole temperatures and formation water chemistry data was performed mainly using a specially designed software package. As a result, every stratigraphic unit is characterized by appropriate hydraulic and thermal parameters.
A sequence of aquifers, aquitards and aquicludes was differentiated. The groundwater flow in the Paleozoic aquifers is regional in nature and mainly horizontal. The flow in the Cretaceous aquifers is of intermediate type, mainly downward oriented. In general, the permeability of the Cretaceous and Paleozoic strata has such low values that the fluid velocity is less than 1 cm/yr.
The convective heat transport in the hydrostratigraphic sequence is negligible with respect to the conductive heat transfer, as shown by the Peclet number of the fluid and heat flow in porous media. The flow of the terrestrial heat flux from the Precambrian basement of the sedimentary basin to the atmosphere is controlled by the variability in the thermal properties of the formations in the basin.
The geothermal gradients were computed by hydrostratigraphic unit using a linear regression fit to the temperature data. As expected, they show higher values for the less conductive layers, and lower values for the more conductive ones. The weighted average, or the integral geothermal gradient of the whole sedimentary column, was computed by considering the difference between the temperature measured at the Precambrian basement and the annual average temperature at the surface. The areal distribution of the integral geothermal gradient (with an average of 22.0 mK/m) shows a strong correlation with the lithology.
The areal temperature distribution for each hydrostratigraphic unit was analyzed by mapping the deviation of the measured value from the computed geothermal gradient. The lateral heat flow from warmer to colder areas is one order of magnitude smaller than the vertical heat flow. In the more homogeneous units, the lateral heat flow presents a trend that seems to reflect the geometry and lithology. 相似文献