Geothermics最新文献_第7页

Assessing thermal regime variability in the San Francisco Basin (Argentina): Heat flow and geothermal gradient anomalies derived from hydrocarbon exploration well data 评估San Francisco盆地（阿根廷）的热状态变化：从油气勘探井数据中得出的热流和地热梯度异常

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-26 DOI: 10.1016/j.geothermics.2025.103522

J.P. Villalba Ulberich , Y.J. Peralta Arnold , M. Taussi , P.J. Caffe , F. Tassi

The Santa Bárbara (SB) mountain range (Andean foreland, northern Argentina) has become increasingly significant in recent years for geothermal exploration, due to the presence of several hot and mineral springs with outlet temperatures of up to 40–60 °C. In this study, bottom-hole temperatures (BHT) from 24 oil wells located within the San Francisco Basin (north of Santa Barbara) were utilized to assess the thermal flow and to investigate the origin of the thermal anomalies. The BHT values, ranging from 44.4 °C to 220.2 °C, indicate a geothermal gradient ranging from 24.9 to 40 °C, a heat flow between 97 and 153 mW/m², and a thermal conductivity of 3.49–4.27 W/mK for the main reservoir unit (Yacoraite Formation). The derived geothermal and geological units, in conjunction with 2D seismic lines and topographic data, were utilized to map relevant structural variations, changes in thickness, and major lithological units. The conceptual model identified the northeastern and southwestern regions as two areas of equal potential for medium- to high-temperature fluid resources. The calculated 'heat-in-place' (HIP) values confirm the substantial geothermal potential of the Yacoraite Formation within the San Francisco Basin by indicating the presence of significant stored thermal energy. The findings of this study demonstrate that integrating well logging and space data with geospatial techniques is an effective method for geothermal prospecting in geological and tectonic settings within foreland environments.

Santa Bárbara （SB）山脉（安第斯山脉，阿根廷北部）近年来在地热勘探方面变得越来越重要，因为它有几个热泉和矿泉，出口温度高达40-60°C。在这项研究中，利用位于旧金山盆地（圣巴巴拉北部）的24口油井的井底温度（BHT）来评估热流并调查热异常的来源。BHT值在44.4 ~ 220.2℃之间，表明主储层（雅长石组）的地温梯度在24.9 ~ 40℃之间，热流在97 ~ 153 mW/m²之间，热导率在3.49 ~ 4.27 W/mK之间。导出的地热和地质单元，结合二维地震线和地形数据，用于绘制相关的构造变化、厚度变化和主要岩性单元。该概念模型将东北和西南地区确定为具有同等中高温流体资源潜力的两个地区。计算出的“就地热”（HIP）值通过表明存在大量储存的热能，证实了旧金山盆地内Yacoraite地层的巨大地热潜力。研究结果表明，将测井、空间数据与地理空间技术相结合是前陆地质构造背景下地热勘探的有效方法。

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引用次数: 0

A comparative study of hydrochemical signatures and formation mechanisms of geothermal waters in the tensile and shear faults of the Tibetan plateau

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-25 DOI: 10.1016/j.geothermics.2025.103540

Xun Huang , Jinhang Huang , Yi Xie , Boyi Zhu , Tao Feng , Hua Wu , Yangshuang Wang , Peng Zhou , Gongxi Liu , Ying Wang , Yunhui Zhang

Geothermal systems hosted by tensile faults in the interior of the Tibetan Plateau display distinct hydrochemical characteristics compared to those in shear faults at the plateau margins, reflecting differences in tectonic controls on fluid flow and heat transport. This study combines tectonic settings with hydrochemical data to investigate the differences and genesis of geothermal water chemistry in these two fault types. Using hydrogeochemical analysis and the Absolute Principal Component Scores-Multiple Linear Regression method, the study quantifies recharge sources, chemical component origins, and reservoir temperatures, and proposes a geothermal water genesis model. The results show that tensile fault-hosted geothermal waters (TFGW) are mainly classified as Cl-Na and Cl·HCO₃-Na types, while shear fault-hosted geothermal waters (SFGW) exhibit HCO₃-Na characteristics. Tensile faults serve as efficient conduits for magmatic heat and fluid, generating high-temperature (260 °C) parent geothermal liquids for TFGW, which mix with cold water to form deep (170.2 °C) and shallow (151.7 °C) reservoirs. In contrast, shear faults limit deep fluid flow, leading to lower deep (169.9 °C) and shallow (127.3 °C) reservoir temperatures. TFGW hydrochemistry is dominated by deep fluid contributions (57.6 %), while SFGW composition is controlled by leaching through granitic rocks (44.1 %) and dissolution of shallow sediments (29.0 %). This study enhances understanding of geothermal genesis and offers insights for sustainable geothermal resource development globally.

本研究结合构造背景和水化学资料，探讨了这两种断裂类型地热水化学的差异及其成因。利用水文地球化学分析和绝对主成分分数-多元线性回归方法，对补给源、化学成分来源和储层温度进行量化，提出了地热水成因模型。结果表明：张性断层型地热水主要表现为Cl- na型和Cl·HCO3-Na型，而剪切型断层型地热水表现为HCO3-Na型；拉伸断层是岩浆热流体的有效通道，为tgw生成高温（260℃）地热母液，与冷水混合形成深部（170.2℃）和浅层（151.7℃）储层。相反，剪切断裂限制深部流体流动，导致深层（169.9℃）和浅层（127.3℃）储层温度较低。TFGW的水化学主要由深部流体贡献（57.6%），而SFGW的组成主要受花岗岩浸出（44.1%）和浅层沉积物溶解（29.0%）的控制。该研究增强了对地热成因的认识，为全球地热资源的可持续开发提供了参考。

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引用次数: 0

Multi-scale fault and fracture networks of the UK’s Mississippian carbonate platforms: implications for extracting geothermal energy 英国密西西比期碳酸盐岩台地的多尺度断层和裂缝网络：对地热能源开采的启示

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-25 DOI: 10.1016/j.geothermics.2025.103513

Maulana Rizki Aditama , Cathy Hollis , Mads Huuse , David Healy

Unlocking the low enthalpy geothermal potential of the UK through heat extraction from Mississippian carbonate platforms (MCP) could support the transition to net-zero carbon emissions by providing a sustainable heat source. However, MCPs remain underexplored compared to analogous formations in Belgium and the Netherlands, largely due to limited understanding of fracture-controlled fluid flow in these low-porosity carbonate systems. This study evaluates the structural and hydraulic characteristics of MCPs through a multi-scale fault and fracture connectivity analysis across regional, local, and outcrop scales in North Wales, adjacent to the Menai Straits Fault System. Using regional fault map and seismic reflection data, drone photogrammetry, outcrop description, and bed scale fracture mapping, we assess fracture geometry, intensity, orientation, and connectivity. Fracture stability was evaluated through slip tendency (Ts) and dilation tendency (Td) analyses under varying stress scenarios, and permeability tensors were derived to characterize flow orientation. Results demonstrate a strong scale-dependency in fracture connectivity. Connectivity coefficients (CL) increase from 0.64 at regional scale to 3.03 at bed scale, while CB (Connection per branch) values rise from 0.71 to 1.58, indicating that smaller-scale datasets capture more complex and transmissive networks. Reactivation analysis shows that fractures subparallel to present-day stress, SHmax (170°) exhibit high dilation tendencies (Td > 0.8), favouring open fluid pathways. Cross-cutting relationships provide field evidence for stress rotation, with implications for multi-phase fracture development and enhanced connectivity near the Menai Straits Fault System. These findings suggest that stress field evolution and structural inheritance significantly influence fracture permeability architecture. The integration of outcrop and subsurface data improves characterization of sub-seismic fracture networks, offering valuable guidance for geothermal drilling strategies and reservoir development in underutilized carbonate platforms.

通过密西西比碳酸盐平台（MCP）的热量提取来释放英国的低焓地热潜力，可以通过提供可持续的热源来支持向净零碳排放的过渡。然而，与比利时和荷兰的类似地层相比，mcp仍未得到充分开发，这主要是由于对这些低孔隙度碳酸盐岩体系中裂缝控制流体流动的了解有限。本研究通过跨区域、局部和露头尺度的多尺度断层和裂缝连通性分析，评估了北威尔士邻近Menai海峡断裂系统的mcp的结构和水力特征。利用区域断层图和地震反射数据、无人机摄影测量、露头描述和层尺度裂缝图，我们评估了裂缝的几何形状、强度、方向和连通性。通过不同应力情景下的滑移趋势（Ts）和扩张趋势（Td）分析来评估裂缝稳定性，并推导渗透率张量来表征流动方向。结果表明，裂缝连通性具有很强的尺度依赖性。连通性系数（CL）从区域尺度的0.64增加到层尺度的3.03，而CB（每分支连接）值从0.71增加到1.58，表明较小规模的数据集捕获了更复杂的传输网络。再激活分析表明，裂缝接近于当前应力，SHmax（170°）表现出高扩张趋势（Td > 0.8），有利于开放流体通道。横切关系为应力旋转提供了现场证据，对Menai海峡断裂系统附近的多相裂缝发育和增强连通性具有重要意义。这些结果表明，应力场演化和构造继承对裂缝渗透率构型有显著影响。露头和地下数据的整合改善了次地震裂缝网络的表征，为未充分利用的碳酸盐岩平台的地热钻井策略和储层开发提供了有价值的指导。

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引用次数: 0

Hydrogeochemical and isotopic evidence for groundwater-geothermal connectivity between Valle de Perote and Los Humeros geothermal field, Mexico 墨西哥Perote山谷和Los Humeros地热田地下水-地热连通性的水文地球化学和同位素证据

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-24 DOI: 10.1016/j.geothermics.2025.103520

Abraham Martínez-González , José Alonso Aguilar-Ojeda , Thomas G. Kretzschmar , Enrique Iñiguez

The Los Humeros Geothermal Field (LHGF), the third most important geothermal power plant in Mexico with an installed capacity of 95 MW, has the potential to double its output. While the hydrological recharge of the LHGF has been previously investigated, refining the systems conceptual model is essential for future development. One recharge zone of particular interest is the Valle de Perote aquifer, where selected wells exhibit elevated temperatures and boron concentrations compared with regional averages, suggesting possible mixing between Perote Valley groundwater and fluids from the LHGF reservoir. The geological framework of the LHGF in the Valle de Perote includes normal faults located outside the Humeros caldera, such as the Alchichica and El Limón faults (Veracruz, Mexico). These structures may facilitate the upward migration of geothermal fluids that interact with the shallow Perote aquifer. This study combines isotopic (δD, δ¹⁸O, δ¹¹B), hydrochemical, and statistical analyses (PCA, Durov, and Piper diagrams) to characterize the origin and evolution of groundwater. The results reveal that most cold and hot water samples are of meteoric origin, with signals of mixing between the sodium-bicarbonate and calcium/magnesium-bicarbonate facies. In contrast, wells located near the geothermal field show enriched boron concentrations and isotopic shifts, suggesting a geothermal contribution. Principal Component Analysis (PCA) and Durov diagrams support the occurrence of geochemical mixing and cation exchange processes, indicating that geothermal fluids migrated into the shallow aquifer of the Perote Valley. This fluid transfer is facilitated by regional fault systems and permeable lithological contacts between volcanic and sedimentary units. The integration of isotopic and hydrochemical tracers provides new evidence for the hydraulic connectivity between the Valle de Perote aquifer and the Los Humeros geothermal system. These findings improve the understanding of fluid flow paths and will support future groundwater management and geothermal resource assessments in the region.

Los Humeros地热田（LHGF）是墨西哥第三大地热发电厂，装机容量为95兆瓦，其发电量有可能翻一番。虽然以前已经对LHGF的水文补给进行了研究，但完善系统的概念模型对于未来的发展至关重要。一个特别值得关注的补给区是Valle de Perote含水层，与地区平均水平相比，该区域的某些井显示出更高的温度和硼浓度，这表明Perote山谷地下水和LHGF储层的流体可能混合在一起。Valle de Perote LHGF的地质格架包括位于Humeros火山口外的正断层，如Alchichica和El Limón断层（墨西哥韦拉克鲁斯）。这些构造可能促进地热流体与浅Perote含水层相互作用的向上运移。本研究结合同位素（δD, δ18O, δ11B），水化学和统计分析（PCA， Durov和Piper图）来表征地下水的起源和演化。结果表明，大部分冷水和热水样品为大气成因，并伴有碳酸氢钠相和钙/镁-碳酸氢钠相混合的信号。相反，靠近地热田的井显示出硼浓度的富集和同位素变化，表明地热对其有贡献。主成分分析（PCA）和Durov图支持地球化学混合和阳离子交换过程的发生，表明地热流体迁移到Perote谷浅层含水层。区域断裂系统以及火山和沉积单元之间的渗透性岩性接触促进了流体的传递。同位素和水化学示踪剂的整合为Valle de Perote含水层和Los Humeros地热系统之间的水力连通性提供了新的证据。这些发现提高了对流体流动路径的理解，并将支持该地区未来的地下水管理和地热资源评估。

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引用次数: 0

Heat source for the Himalayan hot springs: A view from the Puga Geothermal Field, Ladakh, India

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-23 DOI: 10.1016/j.geothermics.2025.103537

Arun Kumar Ojha , Dewashish Kumar , M. Satyanarayanan

India possesses significant potential for geothermal energy development, with several provinces identified suitable for geothermal power generation. Among these, the Puga Geothermal Field was identified in the much-needed and strategically located Ladakh Himalaya and has promising geothermal energy potential. Despite this, significant knowledge gaps about the geothermal fields hinder future exploration and exploitation. The Himalayan and Trans-Himalayan hot springs have been speculatively attributed as magma-derived hot springs similar to the hot springs in Iceland, hence posing considerable uncertainty in their future exploration and exploitation. Using a combined approach of structural geology, geochemistry, and electrical resistivity tomography, this study in the Puga Geothermal Field, Ladakh Himalaya, negated the possibility of magma and proposed an alternative heat source for the geothermal field. The recent/active faults in the region facilitate the meteoric and groundwater to percolate as deep as ∼9 kilometers. Exposed to high temperatures at such depths, the water is heated in the host rock and ascends through the highly permeable active/recent fault zones, eventually emerging at the surface as hot springs. Although the frictional heat during faulting and marginally uplifted geothermal gradient because of ongoing crustal extension partially contributed to the geothermal field, the effect of radioactive heat is neglected because of low radioactive elemental concentration. Additionally, the compiled data from other Himalayan hot springs suggests a similar link with recent/active faults. These observations raise important considerations regarding the sustainability and future exploration of the Puga geothermal energy and have implications for other Himalayan and Trans-Himalayan geothermal fields.

印度具有开发地热能的巨大潜力，已确定几个省适合地热发电。尽管如此，关于地热田的重大知识缺口阻碍了未来的勘探和开发。喜马拉雅和跨喜马拉雅温泉被推测为类似冰岛温泉的岩浆衍生温泉，因此在未来的勘探和开发中存在相当大的不确定性。该地区的新近/活动断层有助于大气和地下水渗透至约9公里深。在这样的深度暴露在高温下，水在宿主岩石中被加热，并通过高渗透性的活动/新近断层带上升，最终以温泉的形式出现在地表。虽然断裂过程中的摩擦热和地壳持续伸展引起的地温梯度轻微上升对地热场有一定贡献，但由于放射性元素浓度较低，放射性热的作用被忽略。此外，从其他喜马拉雅温泉收集的数据表明，与近期/活动断层有类似的联系。这些观察结果对普加地热能源的可持续性和未来勘探提出了重要的考虑，并对其他喜马拉雅和跨喜马拉雅地热田具有启示意义。

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引用次数: 0

Integrated geochemical, radon, and magnetotelluric approaches to assessing the Tampomas geothermal system, Indonesia: Implications for direct-use potential 综合地球化学、氡和大地电磁方法评估印尼Tampomas地热系统：对直接利用潜力的影响

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-22 DOI: 10.1016/j.geothermics.2025.103538

Heri Nurohman , Eka Djatnika Nugraha , Yayat Sudrajat , Teuku Yan W.M. Iskandarsyah , Hendarmawan Hendarmawan

This study investigates the geochemical characteristics, radon concentrations, and subsurface resistivity structures within the Tampomas geothermal system, West Java, Indonesia, to better understand geothermal fluid circulation and its potential for direct-use applications. Fourteen water samples, including thirteen thermal and one cold spring, were analyzed for physicochemical properties, major ions, trace elements, and radon activity. The results show that thermal waters are characterized by elevated temperatures, high conductivity, and enriched concentrations of major ions, reflecting geothermal heating and water–rock interaction. In contrast, the cold spring exhibits low ionic content but anomalously high radon activity, suggesting rapid infiltration and ascent through highly permeable fractures. Statistically, radon concentrations display an inverse correlation with bicarbonate (HCO₃⁻) and calcium (Ca²⁺), indicating that extensive mineral interaction promotes radon degassing or dilution. Ternary plots classify most samples as bicarbonate- and chloride-rich, suggesting fluid mixing between deep geothermal and shallow meteoric sources. Integrating these geochemical and radon results with MT resistivity models reveals conductive zones (<10 Ωm) corresponding to fluid-saturated faults and clay caprocks, and resistive bodies (>100 Ωm) representing impermeable lithologies. The Narimbang thermal spring, located along a major conductive fault zone, displays sulfate enrichment consistent with magmatic gas input. Collectively, these integrated findings delineate the structural–hydrochemical controls on fluid flow and highlight the potential of the Tampomas geothermal system for direct-use development.

本文研究了印度尼西亚西爪哇Tampomas地热系统的地球化学特征、氡浓度和地下电阻率结构，以更好地了解地热流体循环及其直接利用潜力。对14个水样（包括13个热泉和1个冷泉）的理化性质、主要离子、微量元素和氡活性进行了分析。结果表明：该区热水具有温度升高、导电性高、主要离子富集的特点，反映了地热加热和水岩相互作用；相比之下，冷泉表现出低离子含量但异常高的氡活性，表明通过高渗透性裂缝快速渗透和上升。从统计上看，氡的浓度与碳酸氢盐（HCO₃⁻）和钙（Ca 2⁺）呈负相关，表明广泛的矿物相互作用促进了氡的脱气或稀释。三元图将大多数样品分类为碳酸氢盐和氯化物丰富，表明深层地热和浅层大气来源之间存在流体混合。将这些地球化学和氡结果与MT电阻率模型相结合，揭示了导电带（<10 Ωm）对应于流体饱和断层和粘土盖层，电阻体（>100 Ωm）代表不渗透岩性。Narimbang温泉位于主要导电断裂带上，具有与岩浆气体输入相一致的硫酸盐富集特征。总的来说，这些综合发现描绘了流体流动的构造-水化学控制，并突出了Tampomas地热系统的直接利用开发潜力。

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引用次数: 0

3D-seismic channel–floodplain geomorphology of the Rhaetian Distributive Fluvial System in the North German Basin: an integrated workflow with machine learning for geothermal prospects 北德意志盆地雷提亚分流河流系统的三维地震通道-洪泛平原地貌：地热前景的集成工作流程与机器学习

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-22 DOI: 10.1016/j.geothermics.2025.103532

Lorena Bello-Rujana , Matthias Franz , David Lubo-Robles , Inga Moeck

This study addresses the challenge of identifying fluvial reservoir facies within 3D-seismic data of the Rhaetian Distributive Fluvial System (Upper Keuper, Triassic), a major geothermal target in the North German Basin. A workflow integrating seismic amplitude analysis, seismic attributes, and unsupervised machine learning was developed. Seismic amplitude data revealed key fluvial geomorphological features in vertical transects and horizon slices. Principal component analysis (PCA) was used to select the most relevant seismic attributes for clustering. Combining different attribute classes improved fluvial facies classification, enabling more detailed facies maps that clearly delineate key features. Two clustering cases were evaluated: one using seismic amplitude data and another using the selected seismic attributes as input for two clustering methods, PCA and Self-Organizing Maps (SOM), leading to four scenarios. The analysis revealed key fluvial elements of a meandering channel-floodplain system, providing significant insights into fluvial styles, lateral migration patterns, avulsion of channels, and crevasse splay formation. While amplitude-based classification effectively identified fluvial elements, attribute-based clustering provided a finer delineation of internal facies variability and a better discrimination between sand- and mud-prone facies. The workflow remains constrained by seismic resolution and unsupervised learning bias toward dominant features. Nevertheless, the results emphasize the importance of the initial amplitude analysis in guiding the interpretation of seismic attributes and clustering results. This study highlights the value of integrating machine learning into traditional seismic interpretation and enables more accurate morphology-based identification of fluvial reservoir facies, thereby reducing the exploration risk of geothermal targets in the North German Basin.

该研究解决了在德国北部盆地主要地热目标——雷蒂安分流河流系统（上科珀，三叠纪）的3d地震数据中识别河流储层相的挑战。开发了一种集成地震振幅分析、地震属性和无监督机器学习的工作流程。地震振幅数据在垂直断面和水平切片中揭示了关键的河流地貌特征。采用主成分分析（PCA）选择最相关的地震属性进行聚类。结合不同的属性分类改进了河流相的分类，使得更详细的相图能够清晰地描绘出关键特征。评估了两种聚类情况：一种使用地震振幅数据，另一种使用选定的地震属性作为两种聚类方法（PCA和自组织图（SOM））的输入，导致四种场景。分析揭示了曲流河道-洪泛平原系统的关键河流要素，对河流样式、横向迁移模式、河道崩解和裂缝展成提供了重要的见解。虽然基于振幅的分类有效地识别了河流元素，但基于属性的聚类可以更精细地描绘内部相变异性，并更好地区分砂相和泥相。工作流程仍然受到地震分辨率和对主要特征的无监督学习偏差的限制。然而，结果强调了初始振幅分析在指导地震属性解释和聚类结果中的重要性。该研究强调了将机器学习整合到传统地震解释中的价值，可以更准确地识别基于形态的河流储层相，从而降低北德盆地地热目标的勘探风险。

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引用次数: 0

Experimental investigation of flow distribution in enhanced geothermal systems with deep eutectic solvent 深层共熔溶剂强化地热系统流动分布的实验研究

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-21 DOI: 10.1016/j.geothermics.2025.103534

Katrine J.M. Hareland, Eshan K. Maitra, Geir Hareland, Mohammed F. Al Dushaishi

Geothermal energy has been recognized as a valuable alternative to fossil fuels and nuclear power, as it is renewable and reliable. Enhanced Geothermal Systems (EGSs) have the potential to expand geothermal energy production by enabling access to previously untapped geothermal resources. Geothermal short-circuiting poses a significant challenge to EGS development, leading to reduced heat extraction. Deep Eutectic Solvent (DES) exhibits favorable thermal and rheological properties, making it a candidate for geothermal applications. This paper examines Choline Chloride-Based Deep Eutectic Solvent (DES) as a working fluid in geothermal applications and its potential to mitigate geothermal short-circuiting. Hydraulic experiments using a dual fracture flow loop were conducted at high temperatures. The results showed that DES exhibited higher differential pressure behavior compared to water. Flow distribution results revealed that DES enhances flow allocation within the small fracture, particularly when a temperature difference exists between fractures. Specifically, DES increased flow distribution by an average of 11% when the temperature difference was 85°C, and by 13% when the difference was 45°C, relative to water. These findings suggest that DES responds to thermal fracture differences, making it a potential remedy to address geothermal short-circuiting.

地热能已被公认为化石燃料和核能的宝贵替代品，因为它是可再生和可靠的。增强型地热系统（EGSs）有可能通过获得以前未开发的地热资源来扩大地热能的生产。地热短路对EGS的发展提出了重大挑战，导致热量提取减少。深共晶溶剂（DES）具有良好的热学和流变性能，使其成为地热应用的候选材料。本文研究了氯化胆碱基深共熔溶剂（DES）作为地热工作流体的应用及其缓解地热短路的潜力。在高温条件下，采用双裂缝流动环进行了水力试验。结果表明，与水相比，DES具有更高的压差特性。流动分布结果表明，DES增强了小裂缝内的流动分配，特别是当裂缝之间存在温差时。具体来说，相对于水，当温差为85℃时，DES平均增加了11%的流动分布，当温差为45℃时，平均增加了13%。这些发现表明，DES对热裂缝差异有反应，使其成为解决地热短路的潜在补救措施。

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引用次数: 0

The effect of different backfill materials on the thermomechanical behavior of pipe energy piles 不同回填材料对管道能源桩热力学性能的影响

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-21 DOI: 10.1016/j.geothermics.2025.103535

Hong Chang, Zhaoxuan Wang, Qiqi Wu, Xing Wu, Zhengheng Gan

Energy piles serve dual functions: geothermal energy extraction and structural support. While widely adopted for shallow geothermal applications, current research predominantly focuses on solid energy piles, with pipe energy piles remaining relatively unexplored. The inherent hollow section of pipe energy piles facilitates the integration of diverse backfill materials. Therefore, this study investigated the thermomechanical behavior of pipe energy piles with different backfill materials (PEP1: sand soil; PEP2: cement mortar; PEP3: phase-change mortar) using indoor model tests under combined cyclic thermal and mechanical loading. Results indicate that PEP3, enhanced by phase-change materials, exhibited minimal temperature fluctuation within the pile, superior heat exchange efficiency (reaching a steady-state heat transfer rate of 86.4 W/m after 7 cycles), a reduced soil thermal influence zone, lower additional thermal stress, and reduced variation in additional thermal shaft friction compared to PEP1 and PEP2. All backfill materials showed cumulative displacement after 7 cycles. PEP1′s normalized displacement was -0.485, while PEP2 and PEP3 exhibited reductions of approximately 15.9 and 24.9, respectively. Pile tip soil pressure progressively increased with cycle count for all materials, with PEP3 demonstrating the lowest value after 7 cycles. Critically, as cycling progressed, PEP3′s phase-change backfill effectively inhibited the transfer of mechanical load to the pile tip caused by soil cyclic shear action development. This study provides a design basis for optimizing the backfill material of pipe energy piles in actual engineering applications.

能源桩具有地热能提取和结构支撑双重功能。虽然在浅层地热应用中被广泛采用，但目前的研究主要集中在固体能源桩上，而管道能源桩的研究相对较少。管道能源桩固有的空心截面便于多种回填材料的整合。因此，本研究采用室内模型试验研究了不同回填材料（PEP1：砂土；PEP2：水泥砂浆；PEP3：相变砂浆）的管道能源桩在循环热力联合加载下的热力学行为。结果表明，与PEP1和PEP2相比，相变材料增强后的PEP3桩内温度波动最小，换热效率更高（循环7次后达到86.4 W/m的稳态换热率），土壤热影响区较小，附加热应力较小，附加热轴摩擦变化较小。7次循环后，所有回填材料均表现出累积位移。PEP1的归一化位移为-0.485，而PEP2和PEP3分别减少了约15.9和24.9。随着循环次数的增加，桩端土压力逐渐增大，7次循环后，桩端土压力最小。关键是，随着循环的进行，PEP3的相变充填体有效地抑制了土体循环剪切作用发展引起的机械荷载向桩端传递。本研究为实际工程应用中管道能源桩回填材料的优化提供了设计依据。

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引用次数: 0

Geothermal reservoir reinjection: An experimental and numerical study using a large-scale 3D sand tank 地热储层回注：大型三维砂槽的实验与数值研究

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-20 DOI: 10.1016/j.geothermics.2025.103536

Tao Chen , Tong Bai , Yu Zhang , Yabin Yang , Honghao Sheng , Shuai Liu , Zongjun Gao , Fengxin Kang

Long-term and continuous exploitation of hydrothermal systems will cause a drop in groundwater level and ground subsidence. Successful reinjection is important to maintain the hydraulic head of the geothermal reservoir and to yield a sustainable utilization of geothermal energy. This study aims to investigate the reinjection mechanism by combining hydraulic and hydrothermal tests in a large-scale three-dimensional sand tank model (12 m × 6 m × 6 m). We conducted the experiments to observe the hydraulic head and temperature evolution during water reinjection at normal and heated temperatures. The experiment results are compared with the numerical results by using the SHEMAT-Suite software. The trends of hydraulic head and temperature changes match well in general, whereas heat loss due to ambient temperature and physical mechanisms such as particle rearrangement may cause differences between the experimental and numerical results. We optimize reservoir output with respect to the well spacing, porosity, and permeability of the model. Increasing porosity and permeability results in a higher geothermal energy output and better economic benefits. Meanwhile, for the well spacing, it is preferable to have a short spacing in low porosity and permeability models and a long spacing in high porosity and permeability models. The study helps understand the mechanism of reinjection in geothermal reservoirs and optimize the sandstone geothermal exploitation management strategy.

热液系统的长期持续开采将导致地下水位下降和地面沉降。成功的回注对保持地热储层水头和实现地热能源的可持续利用具有重要意义。本研究在大型三维砂槽模型（12 m × 6 m × 6 m）中，通过水力和水热试验相结合的方法研究回注机理。通过实验观察了正常和加热条件下回注水过程中水头和温度的变化规律。利用SHEMAT-Suite软件将实验结果与数值结果进行了比较。水头变化趋势与温度变化趋势总体上吻合较好，但由于环境温度和粒子重排等物理机制导致的热损失可能导致实验结果与数值结果存在差异。我们根据模型的井距、孔隙度和渗透率来优化储层产量。提高孔隙度和渗透率，可以提高地热能产量，提高经济效益。同时，在井距上，低孔渗模型宜采用短井距，高孔渗模型宜采用长井距。该研究有助于认识地热储层的回注机理，优化砂岩地热开发管理策略。

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引用次数: 0