Geothermics最新文献_第8页

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 : 2026-01-01 Epub 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

Thermal characterization of soils in Aveiro and Lisbon for shallow geothermal applications: A study using transient methods 阿威罗和里斯本浅层地热应用的土壤热特性：一项使用瞬态方法的研究

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-01-01 Epub Date: 2025-09-19 DOI: 10.1016/j.geothermics.2025.103498

Rajendra Roka , Ana Vieira , António Figueiredo , Alexandra Ferreira , Claudino Cardoso

Shallow geothermal energy systems are growing as an alternative energy source for building space heating and cooling, with notable contributions to carbon emission reduction. In this context, proper soil thermal characterization is crucial for determining the potential of these systems and evaluating their energy efficiency. This work presents the results of a study of the thermal conductivity of natural soil samples collected from construction sites and boreholes in the cities of Aveiro and Lisbon, Portugal. The evaluation of soil thermal properties was complemented by a comprehensive assessment of soil physical characteristics to establish a broader understanding of their interrelationships, followed by an analysis of the mineralogical composition of the soil. The thermal tests were performed in transient conditions using needle probes and a surface probe and the respective results were compared. Potential sources of error in the various transient probe measurements were examined, including issues such as the impact of water migration due to long-term sample preservation and variations in sample quality. Moreover, the effect of several physical parameters, such as degree of saturation, void ratio and soil density, on the soil thermal conductivity was assessed. As expected, these physical parameters demonstrate a significant influence on thermal characteristics. Additionally, the presence of adequate quartz particles in soil significantly affects the thermal properties of the soil. The study provides initial information for the database regarding the thermal properties of natural Portuguese soil, which can serve as a reference for designing, developing and estimating shallow geothermal systems in these cities.

浅层地热能系统作为建筑空间供暖和制冷的替代能源，在减少碳排放方面的贡献显著。在这种情况下，适当的土壤热特性对于确定这些系统的潜力和评估其能源效率至关重要。这项工作介绍了从葡萄牙阿威罗和里斯本城市的建筑工地和钻孔中收集的自然土壤样本的导热性研究结果。在对土壤热特性进行评估的同时，还对土壤物理特性进行了全面评估，以便更广泛地了解它们之间的相互关系，然后对土壤的矿物学成分进行了分析。在瞬态条件下使用针状探针和表面探针进行热测试，并对各自的结果进行了比较。研究了各种瞬态探针测量中的潜在误差来源，包括由于长期样品保存和样品质量变化而导致的水迁移影响等问题。此外，还评估了饱和度、空隙率和土壤密度等物理参数对土壤导热系数的影响。正如预期的那样，这些物理参数对热特性有显著影响。此外，在土壤中存在足够的石英颗粒显著影响土壤的热性质。该研究为葡萄牙天然土壤热特性数据库提供了初步信息，可为这些城市浅层地热系统的设计、开发和估算提供参考。

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引用次数: 0

Updated 3D resistivity model of the Tres Vírgenes geothermal field (Mexico) from magnetotelluric data: Implications for geothermal exploration and development 基于大地电磁数据的墨西哥Tres Vírgenes地热田三维电阻率更新模型：对地热勘探开发的启示

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-01-01 Epub Date: 2025-10-14 DOI: 10.1016/j.geothermics.2025.103506

Javier González-Garcia , Martyn Unsworth , Oscar Campos-Enríquez , Yanet Antayhua-Vera

A case study is presented involving the 3D inversion of a legacy magnetotelluric (MT) dataset from the Tres Vírgenes Volcanic Complex (TVVC), Baja California Sur, Mexico, which is a significant geothermal energy resource with an installed capacity of 10 MWe. The MT dataset consists of 76 stations acquired between 1992 and 1999 (bandwidth: 0.003 – 100 Hz), and was previously analyzed using 1D, 2D, and 3D approaches, revealing a layered resistivity structure. However, significant uncertainty surrounds the capability of this dataset to resolve deep resistivity structures associated with the magmatic system. This study applies a 3D inversion approach that incorporates topography and bathymetry and inversion tests to assess the sensitivity of the model features to the data. Well-logs and laboratory measurements of resistivity were used to constrain the interpretation. The integrated methodology enabled a more accurate delineation of the resistivity structure of the TVVC, mapping an extensive conductor primarily associated with a brine-saturated smectite clay cap (10 – 60 % clay fraction, 150 – 200 °C). Internal variability within the conductor suggests the presence of a small sill with andesitic mush (30 – 85 % melt fraction) north of El Azufre Volcano, possibly associated with sulphate-type hydrothermal activity along the El Azufre Fault Zone. Moreover, a zone of lower resistivity to the north of the main conductor suggests a possible intrusion of seawater that remains isolated from the main hydrothermal systems in TVVC. Sensitivity tests indicate that the dataset lacks the resolution required to image deep bodies beneath the main conductor; consequently, deep conductors modelled in previous studies are likely inversion artifacts, and are unrelated to the deep magmatic system. These findings have the potential to improve the delineation of the geothermal system boundaries, and provide insights for future geothermal and magnetotelluric exploration.

本文介绍了一个案例研究，涉及对来自墨西哥下加利福尼亚州南部Tres Vírgenes火山复合体（TVVC）的遗留大地电磁（MT）数据集的三维反演，该火山复合体是一个重要的地热资源，装机容量为10兆瓦。MT数据集由1992年至1999年间获得的76个台站（带宽：0.003 - 100 Hz）组成，之前使用1D， 2D和3D方法进行了分析，揭示了层状电阻率结构。然而，该数据集在解决与岩浆系统相关的深部电阻率结构方面的能力存在很大的不确定性。本研究采用了一种三维反演方法，结合地形、测深和反演测试来评估模型特征对数据的敏感性。测井数据和实验室电阻率测量数据被用来约束解释。综合方法能够更准确地描绘出TVVC的电阻率结构，绘制出主要与盐饱和蒙脱石粘土帽（粘土含量为10 - 60%，温度为150 - 200°C）相关的广泛导体。导体内部的变化表明，在El azuure火山北部存在一个小的安山岩泥（30 - 85%熔融分数），可能与El azuure断裂带沿线的硫酸盐型热液活动有关。此外，主导体北部的一个电阻率较低的区域表明，海水可能侵入了TVVC中与主要热液系统隔离的海水。灵敏度测试表明，该数据集缺乏对主导体下方深部物体成像所需的分辨率；因此，以前研究中模拟的深部导体很可能是反演伪影，与深部岩浆系统无关。这些发现有可能改善地热系统边界的划定，并为未来的地热和大地电磁勘探提供见解。

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引用次数: 0

Development and validation of a new model for system-integrated shallow borehole heat exchanger fields with irregular geometry 不规则形状系统集成浅孔换热场新模型的开发与验证

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-01-01 Epub Date: 2025-09-18 DOI: 10.1016/j.geothermics.2025.103481

Xenia Kirschstein , Max Ohagen , Joscha Reber , Clemens Hübler

In the context of reducing greenhouse gas emissions and mitigating climate change, accurate and fast borehole heat exchanger (BHE) field models that can be integrated into the broader system level are required for the design and operation optimisation of shallow geothermal district heating and cooling grids. Available system-integrated BHE field models need adaption in order to fulfil all requirements (high short- and long-term accuracy, low computational cost, varying inlet conditions, irregular field geometries). In this study, a new BHE field model is developed and implemented in TRNSYS. The heat transfer inside the borehole is modelled by adapting an existing thermal resistance and capacitance model for high short-term accuracy for double U-tubes. The borehole wall temperature is prescribed by a combination of g-functions. The proposed model (DynIBF), including various modelling aspects, is validated using existing measured data and models. DynIBF shows to be an adequate supplement to the existing models for irregular BHE fields. The results in the more irregular case are distinctly improved (mean absolute error (MAE)

- 0.63

K from the next best result). On the given hardware, DynIBF is between 8% and 41% faster than the examined existing TRNSYS models.

在减少温室气体排放和减缓气候变化的背景下，需要精确和快速的钻孔热交换器（BHE）现场模型，可以集成到更广泛的系统层面，以设计和优化浅层地热区域供热和供冷电网的运行。现有的系统集成BHE现场模型需要进行调整，以满足所有要求（高短期和长期精度、低计算成本、不同的进口条件、不规则的现场几何形状）。在本研究中，开发了一个新的BHE场模型并在TRNSYS中实现。采用现有的热阻和电容模型来模拟井内的传热，以提高双u型管的短期精度。井壁温度由g函数的组合决定。提出的模型（DynIBF），包括建模的各个方面，使用现有的测量数据和模型进行验证。对于不规则BHE场，DynIBF模型是对现有模型的充分补充。不规则情况下的结果明显改善（平均绝对误差（MAE）比下一个最佳结果低0.63 K）。在给定的硬件上，DynIBF比已测试的现有TRNSYS模型快8%到41%。

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引用次数: 0

Experimental and machine learning-based estimation of the thermal diffusivity of high-plastic soil 基于实验和机器学习的高塑性土壤热扩散系数估计

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-01-01 Epub Date: 2025-09-14 DOI: 10.1016/j.geothermics.2025.103489

Pawan Kishor Sah , Divesh Ranjan Kumar , Shiv Shankar Kumar , Warit Wipulanusat

In many residential areas, power companies are increasingly opting for underground cables for medium- and high-voltage electricity transmission to mitigate weather-related disruptions and ensure safe electricity distribution. Thermal diffusivity (TD) is a critical thermophysical parameter influencing heat transfer processes between heat-sensitive subsurface structures such as underground power cables, ground source heat pumps, and buried hot fluid pipelines and the surrounding soil. The TD of soil is governed by multiple factors, including density, water content, degree of saturation, organic content, and proportions of clay, sand, and silt, rendering its direct measurement both challenging and inherently uncertain. To address these limitations, the present study explores the application of advanced hybrid machine learning models integrating the extreme gradient boosting (XGBoost) algorithm for estimating TD in high-plastic soils. TD measurements were obtained using the dual-probe method (KD2-Pro) in a sunlight-free room under controlled temperature and humidity. A total of 180 experimental datasets comprising bentonite, bentonite–fly ash (silty sand) mixtures, and bentonite–sand mixtures were used to train and validate the models. The model performance and prediction accuracy were evaluated using several performance metrics, scatter plots, and regression error characteristic (REC) curves. The predictions confirm that the integration of metaheuristic optimization significantly enhances the performance of the baseline XGBoost model. Specifically, XGBoost-SSO outperforms the other models (training R² = 0.9744, testing R² = 0.9146), making it the most effective model for predicting soil thermal diffusivity. Moreover, SHapely Additive exPlanations (SHAP) analysis identified Sr (+0.072), Sand (+0.032), and Silt (+0.017) as the most influential features positively impacting the TD of high-plastic soil. While the developed models provide highly accurate forecasts, their inherent "black-box" nature presents interpretability challenges for engineering applications. To mitigate this, an open-source graphical user interface (GUI) was developed on the basis of the trained models, enabling practitioners to generate precise TD predictions efficiently.

在许多居民区，电力公司越来越多地选择地下电缆进行中高压输电，以减轻与天气有关的中断，并确保安全配电。热扩散系数（TD）是影响地下电力电缆、地源热泵、埋地热流体管道等热敏性地下结构与周围土壤之间传热过程的重要热物性参数。土壤的TD受多种因素的影响，包括密度、含水量、饱和度、有机含量以及粘土、沙子和淤泥的比例，这使得直接测量既有挑战性，也具有内在的不确定性。为了解决这些限制，本研究探索了集成极端梯度提升（XGBoost）算法的先进混合机器学习模型在高塑性土壤中估计TD的应用。TD测量采用双探针法（KD2-Pro），在控制温度和湿度的无光照房间中进行。共有180个实验数据集，包括膨润土、膨润土-粉煤灰（粉砂）混合物和膨润土-砂混合物，用于训练和验证模型。使用几个性能指标、散点图和回归误差特征（REC）曲线评估模型的性能和预测精度。预测证实，整合元启发式优化显著提高了基准XGBoost模型的性能。具体而言，XGBoost-SSO优于其他模型（训练R²= 0.9744，测试R²= 0.9146），是最有效的土壤热扩散率预测模型。SHapely加性解释（SHAP）分析表明，Sr（+0.072）、Sand（+0.032）和粉砂（+0.017）是影响高塑性土壤TD的最主要特征。虽然已开发的模型提供了高度准确的预测，但其固有的“黑箱”性质对工程应用的可解释性提出了挑战。为了减轻这种情况，在训练模型的基础上开发了开源图形用户界面（GUI），使从业者能够有效地生成精确的TD预测。

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引用次数: 0

High-resolution mapping of shallow geothermal resources in Spain through multivariate spatial analysis 通过多元空间分析西班牙浅层地热资源的高分辨率制图

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-01-01 Epub Date: 2025-11-08 DOI: 10.1016/j.geothermics.2025.103524

Sergio Alejandro Camargo Vargas, Cristina Sáez Blázquez, Daniel Herranz Herranz, Miguel Ángel Maté-González

Identifying areas with potential for low-enthalpy geothermal energy exploitation is a key step toward sustainable and decentralized energy planning, particularly in countries like Spain, where seasonal high temperatures and marked thermal contrasts influence subsurface heat dynamics. This study presents a nationwide assessment of shallow geothermal potential using a multivariate spatial analysis approach. The methodology integrates key geological and thermal variables, including subsurface temperature gradients at different levels, lithological composition and other influential properties such as thermal conductivity, permeability, and volumetric heat capacity. These parameters were processed through normalization, thematic weighting, map algebra, and spatial classification methods within a GIS-based framework. As a result, geothermal favorability indices were generated, allowing for the identification and mapping of areas with varying levels of potential for low and very low-enthalpy applications. The resulting geothermal potential map was validated through comparison with existing geological information and previously published studies. The outcomes confirm the reliability and applicability of the multivariate approach as a preliminary tool for identifying shallow geothermal resources. This contributes not only to a better understanding of the geothermal landscape in Spain but also to supporting informed decision-making in regional energy planning and sustainable land management strategies.

确定具有低焓地热能源开发潜力的地区是实现可持续和分散能源规划的关键步骤，特别是在西班牙等国家，季节性高温和明显的热差异影响地下热动力学。本文采用多元空间分析方法对全国浅层地热潜力进行了评价。该方法整合了关键的地质和热变量，包括不同层次的地下温度梯度、岩性组成和其他影响性质，如导热系数、渗透率和体积热容。在基于gis的框架内，通过归一化、专题加权、地图代数和空间分类等方法对这些参数进行处理。因此，生成了地热有利指数，从而可以识别和绘制具有不同低焓和极低焓应用潜力的区域。通过与现有地质信息和先前发表的研究结果进行比较，验证了所得的地热潜力图。结果证实了多元方法作为识别浅层地热资源的初步工具的可靠性和适用性。这不仅有助于更好地了解西班牙的地热景观，而且有助于在区域能源规划和可持续土地管理战略方面做出明智的决策。

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引用次数: 0

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 : 2026-01-01 Epub 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

Thermal response of heterolithic deposits in flooded coal mines: implication for heat storage potential 透水煤矿异质岩矿床的热响应：对储热潜力的启示

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-01-01 Epub Date: 2025-11-14 DOI: 10.1016/j.geothermics.2025.103525

Mylene Receveur , Andres Gonzalez Quiros , Alison Monaghan , Vanessa Starcher , Kyle Walker-Verkuil , David Boon , Jeroen van-Hunen

Heat transfer rates are critical to underground heat storage recovery potential and sustainability of thermal abstraction for heating and cooling buildings. A 17-day heat injection – abstraction experiment into a flooded, disused mine working was conducted at the UK Geoenergy Observatory in Glasgow. Analysis of the thermal response of different lithologies intersected by an injection borehole during and after a heat injection experiment is used to quantify the heat exchange between rock mass and circulating mine water. The monitoring data from Distributed Temperature Sensing (DTS) has been analysed and numerical models using COMSOL Multiphysics were developed to characterise the rates and controls on thermal processes during heat injection and recovery. The results suggest the key control of the borehole construction on the temperature change in the first 10 hour of heat injection. In the long term, the thermal response mainly depends on the thermal conductivity of the lithologies. The radial heat transfer reaches a steady charging rate of 23 W/m² and 16 W/m² in the sandstone and clay intervals, respectively, and a maximum of 14 W/m² and 10 W/m² at the start of recovery. This is accompanied by upward heat diffusion/convection from the mine working. This study demonstrates the ability of DTS to identify lithological heterogeneities at a high resolution, and the importance of considering the overburden structure and lithology for thermal storage applications.

传热速率对地下储热回收潜力和采暖制冷建筑的可持续性至关重要。在格拉斯哥的英国地球能源观测站进行了一项为期17天的热注入抽吸实验，该实验是对一个被水淹没的废弃矿井进行的。通过对注热试验期间和试验后注水井相交的不同岩性的热响应分析，量化了岩体与矿井循环水之间的热交换。对分布式温度传感（DTS）的监测数据进行了分析，并使用COMSOL Multiphysics开发了数值模型，以表征热注入和热回收过程中的速率和热过程控制。结果表明，注热前10 h的温度变化是控制钻孔施工的关键。从长期来看，热响应主要取决于岩性的导热性。在砂岩层段和粘土层段，径向换热速率分别为23 W/m2和16 W/m2，在恢复开始时最大换热速率分别为14 W/m2和10 W/m2。这伴随着矿井工作的向上热扩散/对流。这项研究证明了DTS在高分辨率下识别岩性非均质性的能力，以及在储热应用中考虑覆盖层结构和岩性的重要性。

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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 : 2026-01-01 Epub 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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引用次数: 0

Geothermal dynamics of Paleozoic sedimentary systems influenced by Precambrian basement highs and elevated hydrodynamic regimes in the Forebulge zone of the Llanos Basin, Colombia 哥伦比亚Llanos盆地前寒武纪基底隆起影响下古生代沉积体系的地热动力学及水动力机制的提升

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-01-01 Epub Date: 2025-10-24 DOI: 10.1016/j.geothermics.2025.103501

Jose Ricardo Sandoval-Ruiz , Sergio Alberto Jerez-Mogollón , Edgar Ricardo Pérez-Carrillo , Davis Emerson Suarez-Landazabal , Ricardo Andrés Gómez-Moncada , Iliana Karen Copete-Murillo , Nicolás Pérez-Consuegra , Andrés Mora , Jorge Eduardo Sandoval-Muñoz , Darwin Mateus-Tarazona , Cristian Ricardo Mendoza-Blanco , William Mauricio Agudelo-Zambrano , Nelson Sánchez-Rueda , Eduin Orlando Muñoz-Mazo , Silvia Carolina Jerez-Arenas

The geodynamic framework of the geothermal system in the southern Llanos Basin was evaluated using a multiproxy analytical approach integrating geothermal gradient estimation, 3D geological modeling, and detailed hydrogeochemical analyses. Geothermal gradients ranging from 20.0°C/km to 66.7°C/km were calculated from 164 reservoir temperatures derived from PVT tests across 100 oil wells, with recorded temperatures varying between 60.5°C and 133.3°C. The geological model, developed from seismic, structural, petrographic, and petrophysical data, enabled the delineation of lithological sequences and fault-controlled basement highs, and provided insights into reservoir architecture and hydrothermal fluid connectivity. Porosity in Paleozoic units reached up to 23.2%, indicating adequate permeability for geothermal fluid flow. Analyses of 329 water samples, including major ions and stable isotopes, revealed water-rock interactions, mixing processes, and meteoric water influence. Two prospective geothermal zones were identified, coinciding with elevated geothermal gradients, surface recharge areas, and intense fracturing. At depths of ∼3.0 km, predicted reservoir temperatures approach 150 °C, suggesting conditions suitable for geothermal energy generation. These findings highlight geothermal ‘sweet spots’ for exploratory drilling and future developments.

采用地温梯度估算、三维地质建模和详细水文地球化学分析相结合的多代理分析方法，对Llanos盆地南部地热系统的地球动力学框架进行了评价。通过100口油井的PVT测试得出164个储层温度，计算出了20.0°C/km至66.7°C/km的地热梯度，记录温度在60.5°C至133.3°C之间变化。根据地震、构造、岩石学和岩石物理数据建立的地质模型，能够圈定岩性序列和断层控制的基底高点，并为储层构型和热液流体连通性提供见解。古生代单元孔隙度高达23.2%，表明地热流体具有足够的渗透率。对329个水样的分析，包括主要离子和稳定同位素，揭示了水岩相互作用、混合过程和大气水的影响。确定了两个有潜力的地热区，它们与地热梯度升高、地表补给区和强烈压裂相吻合。在~ 3.0 km深度，预测储层温度接近150°C，表明适合地热发电的条件。这些发现突出了地热勘探钻井和未来开发的“最佳区域”。

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引用次数: 0