Geothermics最新文献_第3页

Geothermal resources pathways: the hydrochemical evolution and genesis of geothermal waters in the Xianshuihe fault Zone, eastern Qinghai-Xizang plateau 地热资源途径：青藏高原东部鲜水河断裂带地热水的水化学演化与成因

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-03-01 Epub Date: 2025-12-03 DOI: 10.1016/j.geothermics.2025.103551

Yunhui Zhang , Jinhang Huang , Xingze Li , M. Santosh , Ying Wang , Xingcheng Yuan , Yangshuang Wang , Hongyang Guo , Xiaoyan Zhao , Xun Huang

Exploiting and utilizing geothermal resources require a clear understanding of their genesis mechanisms. Regional fault zones often host abundant geothermal resources whose genesis connections are not well understood. This study aims to elucidate the hydrochemical properties and formation mechanisms of diverse geothermal systems within the Xianshuihe Fault Zone (XFZ), eastern Qinghai-Xizang Plateau. The Self-Organizing Maps and Positive Matrix Factorization algorithms, hydrochemical analysis, and hydrogen-oxygen isotope analysis were employed to identify the intrinsic genesis connections among different types of geothermal waters in the XFZ. The geothermal waters along the XFZ were classified into three groups (Groups 1 − 3). Group 1 is predominantly Cl-Na and Cl·HCO₃-Na types; Group 2 is of HCO₃-Na and SO₄·HCO₃-Na types; and Group 3 primarily belongs to HCO₃-Na and HCO₃-Ca types. The primary source of geothermal water in Groups 1–3 is from fluids stored in deep granitic reservoirs, accounting for 40.1%, 28.8%, and 25.0% in each respective group. The secondary source is the infiltrating cold water leaching the shallow sedimentary rock, contributing 33.5%, 23.6%, and 25.7%, respectively. The primary sources of recharge for the geothermal water in the study area are snow-melting and meteoric water. Group 1 exhibits the highest reservoir temperatures (124.5 °C to 224.1 °C), followed by Group 2 (93.6 °C to 191.7 °C), and Group 3 (75.1 °C to 164.2 °C). This study indicates that the spatial distribution of geothermal water from Group 1 ('Deep Initial Geothermal Water') to Group 2 ('Evolved Shallow Geothermal Water') and Group 3 ('Mixed Shallow Geothermal Water') is a common phenomenon along the XFZ. Based on these findings, this study establishes a conceptual model for different groups of geothermal waters, which also helps establish interconnections among geothermal systems in regional fault zones.

地热资源的开发利用需要对其成因机制有清晰的认识。区域性断裂带往往蕴藏着丰富的地热资源，其成因联系尚不清楚。本研究旨在阐明青藏高原东部鲜水河断裂带不同地热系统的水化学性质及其形成机制。利用自组织图（Self-Organizing Maps）和正矩阵分解（Positive Matrix Factorization）算法、水化学分析和氢氧同位素分析等方法，确定了XFZ不同类型地热水的内在成因联系。沿XFZ的地热水可划分为3类（1 ~ 3类）。第1组以Cl- na型和Cl·HCO3-Na型为主；第2组为HCO3-Na型和SO4·HCO3-Na型；第3族主要属于HCO3-Na型和HCO3-Ca型。1 ~ 3组地热水的主要来源为深部花岗质储层流体，占比分别为40.1%、28.8%和25.0%。次源为浅层沉积岩的渗透冷水淋滤，贡献率分别为33.5%、23.6%和25.7%。研究区地热水补给的主要来源是融雪和大气降水。组1表现出最高的储层温度（124.5°C至224.1°C），其次是组2（93.6°C至191.7°C）和组3（75.1°C至164.2°C）。研究表明，从第1组（“深层初始地热水”）到第2组（“演化浅层地热水”）和第3组（“混合浅层地热水”）地热水的空间分布是XFZ沿线普遍存在的现象。在此基础上，本研究建立了不同组地热水的概念模型，有助于建立区域断裂带地热系统之间的相互联系。

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引用次数: 0

Thermal properties of the lower continental crust: Variabilities and link to other rock properties based on DIVE drill cores and boreholes (Ivrea-Verbano Zone) 下大陆地壳的热性质：基于DIVE岩心和钻孔的变异性及其与其他岩石性质的联系（Ivrea-Verbano区）

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-03-01 Epub Date: 2025-12-24 DOI: 10.1016/j.geothermics.2025.103564

Kim Lemke , György Hetényi , Alexia Secrétan , Junjian Li , Andrew Greenwood , Eva Caspari , Christoph Schmidt , Georgina King , Ueli Schärli , Ludovic Baron , Othmar Müntener

Scarcity of thermal property data on lower crustal rocks and their variability is a major hindrance in constraining the continental geotherm. As part of the ICDP project DIVE, two boreholes have recently sampled 1.5 km of rocks across a lower crustal metasedimentary and a mafic-ultramafic section of the Ivrea-Verbano Zone. Complete drill core recovery and borehole logging allowed us to generate a new, representative dataset of thermal properties ranging from high-resolution measurements to larger scale profiles. Thermal conductivity under ambient conditions varies considerably within every lithology type: felsic lithologies are more variable and show higher averages (∼3.0 W/(m⋅K)) than mafic lithologies (∼2.4 W/(m⋅K)). Radiogenic heat production is generally low and varies considerably between mafic-ultramafic lithologies (∼0.05 µW/m³), felsic lithologies and granulite-facies metasediments (∼0.5 µW/m³), and amphibolite-facies metasediments (∼1.5 µW/m³). Overall, metasediments are the largest contributor to the heat budget of the lower crust, where heat production seems to be related to the protolith, not to the metamorphic grade. Measurements of specific heat capacity, density, and thermal diffusivity also reveal primary differences between felsic and mafic lithologies. There is an inverse semi-logarithmic correlation between density and heat production. The variability of all measured thermal properties is significant at all spatial scales, and increases with increasing scales. Thermal conductivity and diffusivity vary by a factor of ca. 4 within each borehole, and heat production by a factor of 10 between the boreholes. These findings prompt for detailed sampling and comprehensive assessment of thermal property variabilities for applications involving the thermal field.

下地壳岩石热物性资料的缺乏及其变化是制约大陆地热的主要障碍。作为ICDP项目DIVE的一部分，两个钻孔最近在Ivrea-Verbano带的下地壳变质沉积岩和基性-超基性部分取样了1.5公里的岩石。完整的岩心回收和井眼测井使我们能够生成一个新的、具有代表性的热物性数据集，从高分辨率测量到更大规模的剖面。每种岩性类型在环境条件下的导热系数差异很大：长英质岩性变化更大，平均温度（~ 3.0 W/(m⋅K)）高于基性岩性（~ 2.4 W/(m⋅K)）。放射成因产热通常较低，在基性-超基性岩性（~ 0.05 μ W/m3）、长英质岩性和麻粒岩相变质沉积岩（~ 0.5 μ W/m3）和角闪岩相变质沉积岩（~ 1.5 μ W/m3）之间差异很大。总的来说，变质沉积物是下地壳热量收支的最大贡献者，其中热量的产生似乎与原岩有关，而与变质等级无关。比热容、密度和热扩散率的测量也揭示了长英质和基性岩性之间的主要差异。密度和产热之间呈半对数反比关系。所有测量的热物性在所有空间尺度上都具有显著的变异性，并随着尺度的增加而增加。每个井眼内的导热系数和扩散系数变化约为4倍，井眼之间的产热系数变化约为10倍。这些发现促使对涉及热场的应用的热性能变化进行详细采样和全面评估。

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引用次数: 0

Prioritizing resource protection and understanding potential susceptibility of springs to surficial changes in a low-temperature geothermal system 在低温地热系统中，优先考虑资源保护和了解温泉对地表变化的潜在敏感性

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-03-01 Epub Date: 2026-01-24 DOI: 10.1016/j.geothermics.2026.103615

Connor P. Newman , Jeff D. Pepin

Geothermal systems are vulnerable to changes in water budget and composition, requiring science-based management. This study uses a dataset of spring water temperatures, time series of groundwater residence time tracers (tritium and carbon-14), and stable isotopes of water to understand geothermal flow in a low-temperature geothermal system in north west Colorado, United States (Steamboat Springs). The geothermal system is bisected by the Yampa River, necessitating a stream mass balance approach to quantify total discharge. Time series analysis of water temperature data provides a ranked list of features more susceptible to surficial changes, which is corroborated using time series of tritium which indicate spatially distinct patterns of mixing between modern and pre-modern groundwater. All springs contain a portion of pre-modern groundwater that is thousands to tens of thousands of years old, a period coinciding with melting of extensive Pleistocene glaciers that was likely one of the recharge sources to the geothermal system. Stream mass balance indicates that greater than 80% of the total geothermal discharge is derived from diffuse or small springs, highlighting the extensive nature of the geothermal outflow zone and the association with local geologic structures. This study provides baseline data to support management of the Steamboat Springs geothermal system and indicates the utility of these approaches in developing science-based geothermal management.

地热系统容易受到水收支和组成变化的影响，需要基于科学的管理。本研究利用泉水温度数据集、地下水停留时间示踪剂（氚和碳-14）时间序列和水的稳定同位素来了解美国科罗拉多州西北部（Steamboat Springs）低温地热系统中的地热流。地热系统被扬帕河（Yampa River）一分为二，因此需要采用溪流质量平衡方法来量化总排放量。水温数据的时间序列分析提供了一个更容易受地表变化影响的特征列表，这是用氚的时间序列证实的，它表明现代和前现代地下水之间的混合模式在空间上是不同的。所有的泉水都含有数千到数万年前的前现代地下水，这一时期与广泛的更新世冰川融化相吻合，而更新世冰川很可能是地热系统的补给来源之一。水流质量平衡表明，80%以上的地热流量来自漫射或小泉，突出了地热流出带的广泛性及其与当地地质构造的联系。本研究为蒸汽船温泉地热系统的管理提供了基础数据，并指出了这些方法在发展科学地热管理方面的效用。

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引用次数: 0

Professor Manfred Hochstein (1932–2025) 曼弗雷德·霍克斯坦教授（1932-2025）

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-03-01 Epub Date: 2025-12-15 DOI: 10.1016/j.geothermics.2025.103562

Eva Hochstein , Sadiq J. Zarrouk , Alan Nunns

引用次数: 0

Direction-dependent permeability and resistivity of fractured rocks tuned to New Zealand geothermal reservoirs 新西兰地热储层裂缝性岩石的定向渗透率和电阻率

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-03-01 Epub Date: 2026-02-05 DOI: 10.1016/j.geothermics.2026.103620

Alison Kirkby, Cécile Massiot

Understanding permeability in the Earth is vital to optimizing sustainable geothermal development. In many geothermal fields, permeability is controlled by faults, resulting in high spatial and directional variability, difficult to characterise without costly drilling. Electrical resistivity, however, can be measured from the surface, and like permeability, is sensitive to fluids if they are sufficiently conductive. Modelling of resistivity-based geophysical data has largely focussed on isotropic properties to map clay caps and deep heat sources. However, faults commonly have a preferred orientation, and fluid-filled faults often have lower resistivity than the matrix, so anisotropy of permeability and resistivity is expected. This study models faults from the borehole to field scale to characterise direction-dependent permeability and resistivity. Parameters are derived from active faults and geothermal fields in the Taupō Volcanic Zone (TVZ), New Zealand. In our base-case model, permeability is highest (6 × 10^–13 m²) in the horizontal along-dominant-strike direction, lower vertically (5 × 10^–14 m²), and lowest in the across-dominant strike direction (2 × 10^–14 m²), with significant uncertainty in across-strike permeability (4 × 10^–15 m² to 5 × 10^–14 m²). For typical TVZ fluids (0.5 Ωm) and 1000 Ωm matrix, resistivity is lowest along dominant strike (235 Ωm), slightly higher vertically (285 Ωm) and highest across-strike (575 ± 30 Ωm). Resistivity anisotropy ratios along-strike/across-strike are relatively consistent regardless of fault length distribution (∼0.38–0.5), but vary strongly with the proportion of along-strike faults. Anisotropy ratios for permeability are more variable (1–300). The calculated petrophysical properties help link reservoir models with geophysical data, which may guide fractured reservoir models and resource use.

了解地球的渗透率对优化可持续地热开发至关重要。在许多地热田中，渗透率受断层控制，导致空间和方向变化很大，如果不进行昂贵的钻井，很难对其进行表征。然而，电阻率可以从表面测量，和渗透率一样，如果流体具有足够的导电性，电阻率对流体很敏感。基于电阻率的地球物理数据建模主要集中在各向同性属性上，以绘制粘土盖层和深部热源。然而，断层通常有一个优选的方向，并且充满流体的断层通常比基质的电阻率低，因此渗透率和电阻率的各向异性是预期的。该研究从井眼到野外尺度对断层进行建模，以表征方向相关的渗透率和电阻率。参数来源于新西兰陶普火山带（TVZ）的活动断层和地热田。在我们的基本情况模型中，渗透率在沿优势走向的水平方向最高（6 × 10-13 m2），垂直方向较低（5 × 10-14 m2），横向优势走向的渗透率最低（2 × 10-14 m2），横向渗透率（4 × 10-15 m2至5 × 10-14 m2）具有显著的不确定性。对于典型的TVZ流体（0.5 Ωm）和1000 Ωm基质，沿主走向电阻率最低（235 Ωm），垂直电阻率略高（285 Ωm），跨走向电阻率最高（575±30 Ωm）。无论断层长度分布如何，电阻率各向异性比沿走向/沿走向相对一致（~ 0.38 ~ 0.5），但随沿走向断层的比例变化很大。渗透率的各向异性比变化更大（1-300）。计算的岩石物性有助于将储层模型与地球物理数据联系起来，从而指导裂缝性储层模型和资源利用。

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引用次数: 0

Fracture properties, structural heterogeneity, and permeability in the Þeistareykir geothermal system, NE Iceland 冰岛东北部Þeistareykir地热系统裂缝性质、结构非均质性和渗透率

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-03-01 Epub Date: 2026-01-09 DOI: 10.1016/j.geothermics.2026.103596

Aastha , Emma Bramham , Andy Nowacki , Nick Shaw , Anette Mortensen , David Healy

Permeability in the Þeistareykir geothermal system of Iceland is structurally controlled. Natural fracture networks are abundant in Þeistareykir and contribute significantly to fluid flow. Understanding which features enhance permeability and hydraulic conductivity, and how their properties interact with lithology and reservoir structure, is key to predicting reservoir behaviour. To address this, we utilise a range of borehole data to characterise natural fractures in terms of their occurrence, orientation, relative distribution, their relationship with the major lithological units and permeable flow zones in the subsurface. Results show systematic variations in fracture density, thickness, and distribution pattern across different lithologies and depths, with orientations ranging from NNW-SSE, N-S, NNE-SSW to NE-SW. Fractures exhibit the highest intensity in the deeper acidic intrusive units or coarser grained basalt with a predominant N-S-trend and bimodal dip distribution. However, permeability is controlled by a complex interplay of fracture geometry, openness and connectivity rather than simply high fracture abundance or a preferential set of fractures. Permeable feed zones show diverse structural expressions, ranging from high-density fracture clusters and large-aperture fractures to intensely fractured damage zones and multiple intersecting fracture sets. These findings demonstrate that the structural character of the potential fluid-flow channels is highly variable in Þeistareykir. The results of this study can be incorporated into fracture and flow models to enhance our understanding of the permeability distribution and fluid pathways in the Þeistareykir geothermal system.

冰岛Þeistareykir地热系统的渗透率受构造控制。Þeistareykir地区天然裂缝网络丰富，对流体流动有重要贡献。了解哪些特征可以提高渗透率和导电性，以及它们的性质如何与岩性和储层结构相互作用，是预测储层行为的关键。为了解决这个问题，我们利用一系列钻孔数据来描述天然裂缝的产状、方向、相对分布、与主要岩性单元的关系以及地下的可渗透流动带。结果表明，不同岩性和深度的裂缝密度、厚度和分布模式存在系统性变化，取向范围为NNW-SSE、N-S、NNE-SSW至NE-SW。裂缝强度在较深的酸性侵入单元或粗粒玄武岩中最高，以n - s走向为主，呈双峰型倾角分布。然而，渗透率是由裂缝几何形状、开放性和连通性的复杂相互作用控制的，而不仅仅是高裂缝丰度或一组优先裂缝。渗透进料带的结构表现多样，既有高密度裂缝簇和大孔径裂缝，也有强烈的裂缝损伤区和多个相交裂缝组。这些发现表明Þeistareykir中潜在流体流动通道的结构特征是高度可变的。该研究结果可用于裂缝和流动模型，以增强我们对Þeistareykir地热系统渗透率分布和流体路径的认识。

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引用次数: 0

Unveiling geothermal potential in Pinrang regency, Indonesia: Integrated geochemical and geoelectrical characterization 揭示印尼平让地区的地热潜力：综合地球化学和地电学表征

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-03-01 Epub Date: 2025-12-08 DOI: 10.1016/j.geothermics.2025.103565

Muhammad Altin Massinai , Hendra Grandis , Ilham Arisbaya , Muh.Farid Wajedy , Fahruddin Fahruddin , Muhammad Fawzy Ismullah Massinai

Geothermal energy offers a sustainable and low-carbon pathway to meet rising global energy demands, particularly in tectonically active regions such as Pinrang Regency, South Sulawesi, Indonesia. This study presents the first integrated geochemical and geoelectrical characterization of the Lemosusu and Sulili hot springs to evaluate their geothermal potential. Field measurements show surface temperatures between 41 and 46 °C. Geochemical classification using Cl–SO₄–HCO₃ diagrams and silica/Na–K geothermometry indicates that Lemosusu hosts a shallow, bicarbonate-dominated low-enthalpy system (44–77 °C), whereas Sulili contains chloride-rich fluids with reservoir temperatures up to 178 °C, reflecting a more evolved hydrothermal regime. Two-dimensional resistivity imaging reveals distinct subsurface signatures: Lemosusu is characterized by a shallow conductive layer (<5 Ωm) overlying volcaniclastics of the Loka Formation at depths of 10–15 meters, suggesting fluid circulation within porous horizons. In contrast, Sulili displays a vertically continuous conductive zone (<5 Ωm) extending to depths 13 m, coinciding with a mapped fault zone interpreted as a potential main upflow pathway. These findings demonstrate that Lemosusu appears suitable for small-scale direct-use applications such as balneotherapy and greenhouse heating, while Sulili holds potential for binary-cycle power generation. Overall, the integration of geochemical and geoelectrical data provides new insight into how lithologic porosity and fault structures jointly control geothermal fluid flow in mixed volcanic–sedimentary terrains, offering a replicable framework for exploration in under-explored geothermal provinces worldwide.

地热能为满足不断增长的全球能源需求提供了可持续和低碳的途径，特别是在印度尼西亚南苏拉威西岛平朗摄政等构造活跃地区。本文首次对Lemosusu和Sulili温泉进行了地球化学和地电综合表征，以评价其地热潜力。现场测量显示表面温度在41至46°C之间。利用Cl-SO₄-HCO₃图解和silica/ Na-K地热方法进行地球化学分类表明，Lemosusu为浅层碳酸盐岩为主的低焓体系（44 ~ 77℃），而Sulili为富氯化物流体，储层温度高达178℃，反映了更为演化的热液体系。二维电阻率成像显示了明显的地下特征：Lemosusu的特征是在10-15米深的Loka组火山碎屑上覆盖了一层浅层导电层（<5 Ωm），表明孔隙层内存在流体循环。相比之下，Sulili显示出一个垂直连续的导电带（<5 Ωm），延伸至深度13 m，与被解释为潜在主要上行通道的地图断裂带相吻合。这些发现表明，Lemosusu似乎适合小规模的直接使用应用，如水疗和温室加热，而Sulili具有双循环发电的潜力。总体而言，地球化学和地电数据的整合为火山-沉积混合地形中岩性孔隙度和断裂构造如何共同控制地热流体流动提供了新的视角，为全球地热勘探不足地区的勘探提供了可复制的框架。

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引用次数: 0

Performance analysis and geometric evaluation of galvanized T- and Y-Shapes for earth-air heat exchangers using constructal design 基于结构设计的地-空气热交换器镀锌T型和y型的性能分析和几何评价

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-03-01 Epub Date: 2026-01-03 DOI: 10.1016/j.geothermics.2025.103595

Ana M.B. Domingues , Andre L. Razera , Jairo V.A. Ramalho , Michel K. Rodrigues , Honório J. Fernando , Liércio A. Isoldi , Elizaldo D. dos Santos

This study presents a numerical investigation of the performance of Earth-Air Heat Exchanger (EAHE) systems equipped with galvanized structures surrounding the duct. Two geometric configurations (T- and Y-shaped) are evaluated using the Constructal Design method combined with the Exhaustive Search technique. The analysis considers the EAHE thermal potential (TP_EAHE) and the maximum annual efficiency (θ_max), along with a multi-objective assessment based on the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), in which TP_EAHE is treated as a benefit criterion and installation depth as a cost criterion. The results indicate that intermediate installation depths (between 3.7 m and 5.0 m) provide better thermal performance, while deeper configurations do not necessarily result in higher TP_EAHE values. The T-shaped geometry with a balanced proportion between the vertical and horizontal branches, and the Y-shaped geometry with a branching angle of 140 degrees, exhibited superior performance, with improvements above 10% and 5%, respectively, compared to the least favorable geometries. The optimized Y-shaped configuration reached θ_max = 72.0%, achieving a 66.3% gain compared to a conventional case (without galvanized material). The multi-objective analysis demonstrated that there is no universally optimal geometry, but rather a set of effective solutions that emerge depending on the priorities assigned to the system's objectives.

本文研究了在风管周围配置镀锌结构的地-空气热交换器（EAHE）系统的性能。采用结构设计方法结合穷举搜索技术对两种几何构型（T形和y形）进行了评价。该分析考虑了EAHE热势（TPEAHE）和最大年效率（θmax），以及基于理想解决方案相似性偏好排序技术（TOPSIS）的多目标评估，其中TPEAHE被视为效益标准，安装深度被视为成本标准。结果表明，中间安装深度（3.7 m至5.0 m）可以提供更好的热性能，而更深的配置并不一定会导致更高的TPEAHE值。垂直和水平分支比例平衡的t形几何结构和分支角度为140度的y形几何结构表现出优异的性能，分别比最差的几何结构提高了10%和5%以上。优化的y形结构达到θmax = 72.0%，与传统情况（没有镀锌材料）相比，获得66.3%的增益。多目标分析表明，没有普遍最优的几何形状，而是根据分配给系统目标的优先级出现的一组有效解决方案。

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引用次数: 0

From Outcrop to Groundwater Flow: The Impact of Overlooked Heterogeneity on Advective Transport in Lower Triassic Sandstones, Eastern France 从露头到地下水流动：被忽视的非均质性对法国东部下三叠统砂岩平流输运的影响

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-03-01 Epub Date: 2025-12-29 DOI: 10.1016/j.geothermics.2025.103581

Lucas Bofill , Gerhard Schäfer , Guilherme Bozetti , Jean-François Ghienne , Mathieu Schuster

Sandstone aquifers lacking mudstone interbeds are often considered homogeneous. However, depositional processes and diagenesis can generate significant permeability contrasts without notable variations in granulometry. Capturing this heterogeneity in flow models is essential but challenging. Outcrop studies provide valuable analogues for subsurface conditions, revealing sedimentary architectures and facies distributions not observable from borehole data alone. This study focuses on the Lower Grès Vosgien formation in eastern France, an important aquifer hosting lithium-rich geothermal brines in the Upper Rhine Graben, deposited by braided fluvial and aeolian systems during the Lower Triassic. This work aims to evaluate the influence of decimetre- to metre-scale sandstone features on advective transport modelling, through a two-dimensional conceptual model developed using a digital outcrop model and sedimentary facies analysis. Six progressively simplified hydrostratigraphic models are tested to assess how heterogeneity and its representation affect particle residence times, breakthrough curves, longitudinal macrodispersivity, and upscaled anisotropy. Results indicate that distinguishing fluvial- and aeolian-related sandstones significantly influences both horizontal and vertical advective flow. Failure to discretise individual fluvial facies and reliance on deterministic hydraulic conductivity values led to the underestimation of preferential flow pathways, delaying the prediction of first particle arrivals. Moreover, the discretisation between fluvial and aeolian-related deposits significantly affects macrodispersion results and yields considerable anisotropy when the conceptual model is upscaled. The strong coupling between advective flow with heat transfer and solute transport underscores the critical role of the observed sedimentary heterogeneity on the accurate understanding of lithium-rich geothermal brines circulation in the matrix porosity of the Lower Triassic sedimentary successions in the Upper Rhine Graben reservoirs.

缺乏泥岩互层的砂岩含水层通常被认为是均匀的。然而，沉积过程和成岩作用可以产生显著的渗透率对比，而粒度变化不显著。在流模型中捕获这种异质性是必要的，但也是具有挑战性的。露头研究为地下条件提供了有价值的类似物，揭示了仅凭钻孔数据无法观察到的沉积结构和相分布。本研究以法国东部的下gr Vosgien组为研究对象，该组是上莱茵地堑中富含锂地热盐水的重要含水层，由辫状河和风成体系在下三叠世沉积而成。这项工作旨在通过使用数字露头模型和沉积相分析开发的二维概念模型，评估分米至米尺度砂岩特征对平流输运建模的影响。测试了六种逐步简化的水文地层模型，以评估非均质性及其表征如何影响颗粒停留时间、突破曲线、纵向宏观分散性和大尺度各向异性。结果表明，河流和风成相关砂岩的区分对水平和垂直平流都有显著影响。未能离散单个河流相和依赖确定性的水力导率值导致低估了优先流动路径，延迟了第一次颗粒到达的预测。此外，当概念模型扩大时，河流沉积和风成沉积之间的离散化显著影响宏观离散结果，并产生相当大的各向异性。平流换热与溶质输运之间的强耦合凸显了沉积非均质性对准确理解上莱茵地陷下三叠统储层基质孔隙中富锂地热盐水循环的重要作用。

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引用次数: 0

Improving borehole fracture characterization using oriented sidewall cores for geothermal assessment – an example in central New York State USA 利用定向侧壁岩心改进井眼裂缝特征，用于地热评价——以美国纽约州中部为例

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2026-03-01 Epub Date: 2026-01-20 DOI: 10.1016/j.geothermics.2025.103589

Sean A. Fulcher , Teresa E. Jordan , Stephen E. Laubach , Sara J. Elliott , Valeria Nogales Herrera

In New York State and Pennsylvania, USA, Precambrian metamorphic and intrusive rocks and Cambrian to Lower Ordovician sedimentary rocks are reservoir targets for deep direct-use geothermal development. Evaluation of natural fractures and structures in the potential reservoir units at the Cornell University Borehole Observatory site was conducted through cross-scale evaluation of oriented sidewall cores, borehole image (BHI), and far-field acoustic survey data. Oriented sidewall cores in the basement complex (Cayuta Formation) reveal metasediments containing foliations, lineations, mineral-filled fractures, and breccia intervals. Basement sidewall core fracture data aid identification of fractures in BHI surveys riddled with borehole breakouts. In contrast, sidewall and image log data for the Cambrian-Ordovician sedimentary section show that open fractures are present and allow orientation and abundance to be estimated. At various depths sandstone and dolostone sidewall cores contain quartz-filled or carbonate-filled bed-normal and -parallel microfractures. Four subvertical microfracture sets, formed sequentially, strike NW-SE (F1), NE-SW (F2), N-S (F3), and WSW-ENE (F4). Microfracture set orientations F1, F2, and F4 match interpretations of acoustic fracture anomalies (open fractures) located tens of meters from the wellbore. In the uppermost Galway Formation sandstone, common microfracture apertures are 0.001 to 0.01 mm. The widest microfractures transition to quartz-lined and bridged open macrofractures. An open vertical macrofracture in Galway sandstone is observed in BHI surveys and a sidewall core, effectively ground-truthing the F4 fracture set. Based on comparison of core fractures with borehole image survey features, differentiation of natural from drilling-induced fractures reveals three sedimentary rock zones of elevated natural fracture frequency.

在美国纽约州和宾夕法尼亚州，前寒武纪变质岩和侵入岩以及寒武系至下奥陶统沉积岩是深层直接利用地热开发的储层目标。通过对定向侧壁岩心、钻孔图像（BHI）和远场声学测量数据进行跨尺度评价，对康奈尔大学钻孔观测站潜在储层单元中的天然裂缝和结构进行了评价。基底杂岩（Cayuta组）的定向侧壁岩心显示出含有片理、线理、含矿物裂缝和角砾岩层的变质沉积物。基底侧壁岩心裂缝数据有助于识别井眼突出的BHI调查中的裂缝。相比之下，寒武-奥陶系沉积剖面的侧壁和成像测井资料显示，裂缝存在，可以估计裂缝的方向和丰度。在不同深度的砂岩和白云岩侧壁岩心中含有石英充填或碳酸盐岩充填的层向和平行微裂缝。四个亚垂直微裂缝组依次形成，走向NW-SE （F1）、NE-SW （F2）、N-S （F3）和WSW-ENE （F4）。微裂缝集方向F1、F2和F4与距离井筒数十米的声波裂缝异常（张开裂缝）的解释相匹配。在最上层的Galway组砂岩中，常见的微裂缝孔径为0.001 ~ 0.01 mm。最宽的微裂缝转变为石英衬砌和桥接的开放大裂缝。在BHI调查和侧壁岩心中观察到Galway砂岩中有一条开放的垂直大裂缝，有效地对F4裂缝集进行了地面验证。通过岩心裂缝与钻孔图像测量特征的对比，对天然裂缝与钻井裂缝进行了区分，揭示了天然裂缝频率升高的3个沉积岩带。

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