Geothermics最新文献_第7页

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

Mineral-mechanical heterogeneity of natural fractures in crystalline rocks: A case study from Utah FORGE 结晶岩天然裂缝的矿物-力学非均质性：以犹他州弗吉格为例

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-19 DOI: 10.1016/j.geothermics.2025.103529

Ettehadi A, Mutume B, Radonjic M

This study presents a multi-scale investigation of mineralogical, structural, and mechanical heterogeneity in a naturally fractured crystalline granite core from Utah FORGE Well 16A (78)-32, retrieved from a depth of 5476.5 ft. Although outside the active injection interval, the sample shares mineralogical and structural features with deeper formations, offering valuable analog insights into fracture behavior in crystalline geothermal reservoirs. X-ray Diffraction (XRD) and Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) revealed a quartz–feldspar–clay–carbonate assemblage, with quartz and feldspars forming the primary framework and localized enrichment of kaolinite and siderite along fracture interfaces, indicative of hydrothermal alteration. Micro-Computed Tomography (micro-CT) imaging captured a structurally heterogeneous fracture, with mineralized flanks and an unsealed central gap, reflecting episodic sealing and variable fluid–rock interactions. Nanoindentation measurements quantified distinct phase-specific mechanical properties. Quartz (E ≈ 79 GPa, H ≈ 12 GPa) and siderite (E ≈ 154 GPa, H ≈ 7.7–9 GPa) exhibited high stiffness and hardness, supporting mechanical integrity under stress. In contrast, kaolinite (E ≈ 24 GPa, H ≈ 3 GPa) was mechanically weak and ductile. Ankerite, a dominant component of the fracture cement, exhibited moderate stiffness (E ≈ 109 GPa) and hardness (H ≈ 6.6 GPa), contributing to fracture wall reinforcement. Mineral interfaces involving kaolinite demonstrated reduced stiffness and increased plasticity, marking them as potential zones for deformation or reactivation. Based on these micromechanical contrasts, four mineral-mechanical domains were delineated: brittle quartz-rich, semi-brittle feldspar-rich, ductile/reactive clay-carbonate, and mechanically heterogeneous interface zones. This classification provides a framework for translating microscale observations into reservoir-scale behavior predictions. Mechanical domain properties are suited for integration into numerical models of fracture propagation, sealing, and permeability evolution under geothermal conditions. While the study focuses on a shallow core, the findings are transferable to deeper, hotter intervals and contribute to improving fracture stability modeling in high-temperature crystalline systems.

本研究对犹他州FORGE 16A(78)-32井的天然裂缝结晶花岗岩岩心进行了多尺度的矿物学、结构和力学非均质性研究，该岩心深度为5476.5英尺。尽管在活跃注入层段之外，该样品与更深地层具有相同的矿物学和结构特征，为晶体地热储层的裂缝行为提供了有价值的模拟分析。x射线衍射（XRD）和扫描电子显微镜及能谱分析（SEM-EDS）显示石英-长石-粘土-碳酸盐组合，石英和长石构成主要骨架，高岭石和菱铁矿沿裂缝界面局部富集，表明热液蚀变作用。微计算机断层扫描（micro-CT）成像捕获了一条结构上不均匀的裂缝，侧翼矿化，中心空隙未封闭，反映了幕式密封和可变的流体-岩石相互作用。纳米压痕测量量化了不同相的机械性能。石英（E≈79 GPa, H≈12 GPa）和菱铁矿（E≈154 GPa, H≈7.7-9 GPa）具有较高的刚度和硬度，在应力作用下保持机械的完整性。而高岭石（E≈24 GPa, H≈3 GPa）的力学性能较弱，具有延展性。Ankerite是裂缝水泥的主要成分，具有中等的刚度（E≈109 GPa）和硬度（H≈6.6 GPa），有助于裂缝壁的加固。涉及高岭石的矿物界面显示出刚度降低和塑性增加，标志着它们是变形或再激活的潜在区域。基于这些微观力学对比，圈定了4个矿物-力学区域：脆性富石英区、半脆性富长石区、韧性/活性粘土-碳酸盐岩区和机械非均质界面区。这种分类为将微观尺度的观测结果转化为油藏尺度的行为预测提供了一个框架。在地热条件下，力学域特性适合集成到裂缝扩展、密封和渗透率演化的数值模型中。虽然研究主要集中在浅层岩心，但研究结果可应用于更深、更热的层段，并有助于改进高温晶体系统的裂缝稳定性建模。

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引用次数: 0

Application of the Monte Carlo method for geothermal resource assessment in low-exploration, high-potential areas: A case study of the Longchuan Basin, Southwest China 蒙特卡罗方法在低勘探高潜力地区地热资源评价中的应用——以龙川盆地为例

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-19 DOI: 10.1016/j.geothermics.2025.103531

Xiaoxue Jiang , Chuanqing Zhu , Fang Xie , Yuanjin Sun , Qian Cao , Dong Sun , Chaohe Fang , Yonghui Huang , Yaodong Xu

The Longchuan Basin, located in the high-temperature geothermal zone of the Mediterranean-Himalayan region, exhibits significant geothermal potential due to intense tectonic activity and a high heat flow background. However, limited exploration and insufficient data have hindered accurate resource assessment. In this study, reliable heat flow values were obtained through systematic drilling temperature measurements and core thermal property analysis, clarifying the spatial distribution of the basin’s temperature field. Using the Monte Carlo volumetric method, key reservoir parameters such as temperature, thickness, and porosity were modeled to quantify the uncertainty of geothermal resource estimates. Results show an average geothermal gradient of 3.87 °C/100 m and surface heat flow ranging from 70 to 90 mW/m². The hydrothermal resource potential is characterized by a P10 of 4.10 × 10¹⁴ KJ, a P50 of 8.87 × 10¹⁴ KJ, and a P90 of 1.59 × 10¹⁵ KJ. For hot dry rock resources, the P10, P50, and P90 values are 1.21 × 10¹⁶ KJ, 1.32 × 10¹⁶ KJ, and 1.43 × 10¹⁶ KJ, respectively. Compared with conventional methods, the Monte Carlo approach effectively captures parameter uncertainty, improving assessment reliability. This study provides a methodological reference for geothermal exploration in under-explored basins with high geothermal potential.

龙川盆地位于地中海-喜马拉雅地区的高温地热带，构造活动强烈，热流背景高，地热潜力突出。然而，有限的勘探和不足的数据阻碍了准确的资源评价。本研究通过系统的钻井测温和岩心热物性分析，获得了可靠的热流值，厘清了盆地温度场的空间分布。利用蒙特卡罗体积法，对温度、厚度和孔隙度等关键储层参数进行建模，量化地热资源估算的不确定性。结果表明，平均地温梯度为3.87°C/100 m，地表热流为70 ~ 90 mW/m²。热液资源潜力的P10值为4.10 × 10¹⁴KJ， P50值为8.87 × 10¹⁴KJ， P90值为1.59 × 10¹⁴KJ。干热岩资源的P10、P50和P90分别为1.21 × 10¹26 KJ、1.32 × 10¹26 KJ和1.43 × 10¹26 KJ。与传统方法相比，蒙特卡罗方法有效地捕捉了参数的不确定性，提高了评估的可靠性。该研究为地热潜力大的未开发盆地的地热勘探提供了方法参考。

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On the use of thermal response tests for deep geothermal exploration in urban areas: A case study made on the Greater Montréal (Canada) 关于在城市地区使用热响应测试进行深层地热勘探：以大蒙特兰萨达尔为例研究（加拿大）

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-11-15 DOI: 10.1016/j.geothermics.2025.103523

Mafalda M. Miranda , Madeline Chapelet , Félix-Antoine Comeau , Jasmin Raymond , J. Christian Dupuis , Philippe Pasquier , Chrystel Dezayes

Exploring deep geothermal resources can be challenging in dense urban environments and therefore a preliminary screening for suitable target areas using existing data from, for example, the geothermal heat pump industry can help de-risk projects at the early exploration phase. Thermal response tests (TRTs) with initial ground temperature measurements can be used to estimate terrestrial heat flux, a metric to indicate suitable areas for deep geothermal development. The greater the heat flux value, the greater the area suitability. This does not replace deep geothermal exploration drilling for a more accurate assessment of the ground temperature but can help target areas of interest and provide a source of unexploited data. This hypothesis was tested in a study aiming to improve knowledge on deep geothermal resources over the Greater Montréal Area (Canada). TRT datasets were analyzed at 22 locations to estimate the terrestrial heat flux. The results were then compared to heat flux estimates made with bottom-hole temperature data and equilibrium temperature profiles from the 6 deep wells available in the area. Both datasets show a certain degree of correlation. To support these findings, a 400 m deep geothermal exploration well was drilled to provide an accurate equilibrium temperature profile in a zone of interest. The data retrieved from this well validated the results and confirmed that, in this setting, TRT can be used as a de-risking tool for deep geothermal exploration.

在人口密集的城市环境中，勘探深层地热资源可能具有挑战性，因此，利用现有数据对合适的目标区域进行初步筛选，例如，地热热泵行业可以帮助降低项目在早期勘探阶段的风险。具有初始地温测量的热响应测试（trt）可用于估计地热通量，这是一种指示适合进行深层地热开发的地区的度量。热流密度值越大，面积适宜性越大。这并不能取代深层地热勘探钻井，以获得更准确的地温评估，但可以帮助目标区域，并提供未开发的数据来源。这个假设在一项研究中得到了验证，这项研究的目的是提高对大蒙塔姆地区（加拿大）深层地热资源的认识。对22个地点的TRT数据集进行了分析，以估计地面热通量。然后将结果与根据该地区6口深井的井底温度数据和平衡温度剖面估算的热流密度进行比较。两个数据集显示出一定程度的相关性。为了支持这些发现，钻了一口400米深的地热勘探井，在感兴趣的区域提供了准确的平衡温度剖面。从该井中获取的数据验证了结果，并证实在这种情况下，TRT可以作为深层地热勘探的降低风险的工具。

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引用次数: 0