Geothermics最新文献_第9页

The source and differential enrichment mechanisms of lithium in Gudui geothermal field: Constraints from enrichment and dilution processes of geothermal-type lithium 古堆地热田锂的来源和差异富集机制：地热型锂的富集和稀释过程的制约因素

IF 3.5 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2024-11-08 DOI: 10.1016/j.geothermics.2024.103190

Rui Cao , Yiming Yan , Ji Dor , Qijun Liu , Yongqiang Cai , Shuangshuang Wan , Defan Chen

As a typical high-temperature geothermal system in the Qinghai-Xizang Plateau, the Gudui geothermal field (GDGF) shows notably high lithium content. Compared with other Li-rich geothermal fields, GDGF exhibits differential enrichment of lithium. Furthermore, few studies have focussed on investigation of the depletion of lithium during the ascent of geothermal fluids. Therefore, this study investigated the source, mechanism of differential enrichment of lithium and depletion mechanism of lithium. The δ_D and δ18O plot and the two-endmember modeling of Sr isotope indicate that geothermal fluids in GDGF were affected by magmatic water and mixing ratios are range from 0.8 to 12 %. Furthermore, the Li isotope mass balance model shows that the leucogranite distributed near GDGF is the primary source of lithium in geothermal fluids. The correlations between Na, K, Li and Cl concentrations indicate that the geothermal waters in eastern and western region originate from different parent geothermal fluids. The δ_D-Cl plot and enthalpy-chloride diagram reveals that the geothermal water in WGDGF was mainly formed by mixing with shallow surface water, and multiple boiling processes took place in EGDGF. In addition, Lithium in the geothermal fluids might be absorbed by the clay minerals widely distributed in the EGDGF, which causes the depletion in the rise process. In conclusion, the differential enrichment model of lithium in GDGF was constructed.

作为青藏高原典型的高温地热系统，古堆地热田（GDGF）的锂含量明显较高。与其他富锂地热田相比，古堆地热田表现出不同程度的锂富集。此外，很少有研究关注地热流体上升过程中的锂损耗。因此，本研究调查了锂的来源、差异富集机制和耗竭机制。δD和δ18O图以及锶同位素的二元模型表明，广东地热区的地热流体受到岩浆水的影响，混合比在0.8%至12%之间。此外，锂同位素质量平衡模型表明，分布在广东地热区附近的白云岩是地热流体中锂的主要来源。Na、K、Li和Cl浓度之间的相关性表明，东部和西部地区的地热水来源于不同的母地热流体。δD-Cl图和焓氯图显示，WGDGF中的地热水主要是与浅层地表水混合形成的，而在EGDGF中发生了多次沸腾过程。此外，地热流体中的锂可能被广泛分布于 EGDGF 中的粘土矿物吸收，从而导致上升过程中的耗竭。综上所述，构建了地热锂富集模型。

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引用次数: 0

Experimental assessment of inter-well reinjection in standing column wells by analysis of transfer functions obtained from non-stationary deconvolution 通过分析非稳态解卷积获得的传递函数，对立柱井的井间回注进行实验评估

IF 3.5 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2024-11-06 DOI: 10.1016/j.geothermics.2024.103184

Louis Jacques, Philippe Pasquier, Gabriel Dion, Gabrielle Beaudry

Standing column wells are semi-open-loop ground heat exchangers that can achieve highly efficient thermal exchange rates through the strategic control of the pumping and bleed flow rates. The management of groundwater discharges associated with bleed use remains a challenge. A solution is inter-well reinjection, which proposes to imbalance the return flow rates between the standing column wells. This approach has been shown to be more efficient than fully balanced recirculation, although a direct comparison with a conventional bleed operation has not yet been conducted. To provide a robust evaluation of inter-well reinjection performance, a 35-day-long experiment is conducted on five standing column wells connected to a real building. The experimental transfer functions representing the operating modes tested (full recirculation, bleed, and inter-well reinjection) are evaluated using a non-stationary deconvolution algorithm and their adequacy with the conceptual site model is verified by comparison with numerical transfer functions obtained in a Monte-Carlo experiment. The results indicate that inter-well reinjection leads to a 10% higher thermal efficiency in the scenarios tested compared to full recirculation, albeit with a slightly reduced performance compared to typical bleed use. This confirms the potential of inter-well reinjection for boosting the efficiency of thermal exchange in SCWs while facilitating groundwater management and avoiding the installation of costly injection facilities. The methodology used to evaluate the experimental transfer functions is also found to be robust, as it allowed the reproduction of the measured temperatures with a root mean square error of 0.04

° C

. Lastly, comparison of the experimental transfer functions with the Monte-Carlo experiment suggests that the accuracy of the conceptual model could be improved.

立柱井是一种半开环地热交换器，可通过对抽水和放水流量的战略控制实现高效的热交换率。与放水量相关的地下水排放管理仍然是一项挑战。一种解决方案是井间回注，它建议平衡立柱井之间的回流量。尽管尚未与传统的放流操作进行直接比较，但这种方法已被证明比完全平衡的再循环更有效。为了对井间回注性能进行可靠评估，我们对连接到真实建筑物的五口立柱井进行了长达 35 天的实验。使用非稳态解卷积算法评估了代表测试操作模式（完全再循环、放空和井间回注）的实验传递函数，并通过与 Monte-Carlo 实验中获得的数值传递函数进行比较，验证了它们与概念站点模型的匹配性。结果表明，在所测试的情况下，井间回注的热效率比完全再循环高 10%，尽管与典型的放空相比性能略有下降。这证实了井间回注在提高超临界水厂热交换效率方面的潜力，同时促进了地下水管理，避免了安装昂贵的注入设施。用于评估实验传递函数的方法也被认为是稳健的，因为它可以再现测量温度，均方根误差仅为 0.04 °C。最后，实验传递函数与蒙特卡洛实验的比较表明，概念模型的准确性还有待提高。

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引用次数: 0

The certainty matrix for fault data and interpretations 断层数据和解释的确定性矩阵

IF 3.5 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2024-11-06 DOI: 10.1016/j.geothermics.2024.103197

D.C.P. Peacock

This paper introduces an approach for expressing certainty in the analysis and interpretation of faults, using a modification of the risk matrix commonly used in risk assessment. The certainty matrix uses qualitative or semi-quantitative analyses of both the data used and an interpreted characteristic of individual faults or fault systems. These characteristics may include the existence of faults, the certainty of trace lengths, the age of faults, or the influence of faults on sub-surface fluid flow. This approach improves the ability to make justifiable interpretations and decisions about faults and fault-affected areas, including about issues relevant to geothermal energy exploration or the underground storage of radioactive waste. The use of this approach is illustrated using three faults from Somerset, UK.

本文介绍了一种在分析和解释断层时表达确定性的方法，使用的是对风险评估中常用的风险矩阵的一种修改。确定性矩阵使用定性或半定量分析所使用的数据以及所解释的单个断层或断层系统的特征。这些特征可能包括断层的存在、迹线长度的确定性、断层的年龄或断层对地下流体流动的影响。这种方法提高了对断层和受断层影响区域做出合理解释和决策的能力，包括对地热能源勘探或放射性废物地下储存相关问题的解释和决策。英国萨默塞特郡的三个断层说明了这种方法的使用。

引用次数: 0

Investigation of radiogenic heat production in granites of the Goiás Tin Province, Central Brazil 巴西中部戈亚斯锡矿省花岗岩放射性产热调查

IF 3.5 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2024-11-01 DOI: 10.1016/j.geothermics.2024.103183

A.L. Carvalhêdo , A.C. Carmelo , J.P.D. Lima , N.F. Botelho , A. Chornobay

This study defines the radiogenic heat production of A-type granites in the Goiás Tin Province (GTP), Central Brazil, using airborne gamma-ray spectrometry. Pedra Branca Massif and Serra Dourada Granite are rich in tin, rare earth elements, and they exhibit anomalous radiogenic heat (5.5–15 µW/m³). They are therefore classified as high heat production granites (HHPG). By integrating radiogenic heat data, RGB imaging, magnetometry, density model and geological information, we associated anomalous radiogenic heat with mineralized regions present in the granites found in the GTP. Our methodology was validated using geological information, density model and other granites worldwide. It proved to be effective for targeting HHP granites.

这项研究利用机载伽马射线光谱仪确定了巴西中部戈亚斯锡矿省（GTP）A 型花岗岩的辐射热产生情况。Pedra Branca块岩和Serra Dourada花岗岩富含锡和稀土元素，它们表现出异常的辐射热（5.5-15 µW/m³）。因此，它们被归类为高产热花岗岩（HHPG）。通过整合放射热数据、RGB 成像、磁力测量、密度模型和地质信息，我们将异常放射热与 GTP 发现的花岗岩中存在的矿化区域联系起来。我们使用地质信息、密度模型和全球其他花岗岩验证了我们的方法。事实证明，该方法可有效锁定高热值花岗岩。

引用次数: 0

Influence of ground source heat exchanger operation modes on multi-borehole mid-deep ground source heat pump system performance 地源热泵换热器运行模式对多钻孔中深层地源热泵系统性能的影响

IF 3.5 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2024-10-30 DOI: 10.1016/j.geothermics.2024.103186

Zuohai Wang , Jian Ding , Mingzhi Yu , Yudong Mao , Ke Zhu , Wenke Zhang , Ping Cui , Zhaoyi Zhuang , Shiyu Zhou

The operation economy of mid-deep ground source heat pump (MGSHP) system is significantly influenced by the operation mode of multi-borehole mid-deep borehole heat exchangers (MMBHE). However, as to now, the understanding about it is very limited and far from enough. This study explores the effects of the MMBHE different operating modes on the performance of MGSHP system, and the factors such as full boreholes operation arrangement, circulating water flow rate variation of individual boreholes, and building heating load variations during the heating season. The study analyzed the circulating water temperature variation, underground temperature field distribution and evolution, heat pump unit COP, coefficient of system performance (CSP), heat extraction of MMBHE, reverse heat transfer depth of MBHE, and power consumption. The results indicate that the operation mode of letting all boreholes operate throughout the whole heating season and reducing circulating water flow rate when the heating load is small and increasing it while the load is large is much better than other operation modes. With this kind of operation mode, the MGSHP system has the lowest power consumption. Even though the overall borehole extracts heat from the ground, the upper section of the borehole sometimes injects heat. The length of the heat release section can be effectively shortened by reducing the circulating water flow rate and decreases as the operation time extends. The reduction is most significant when all boreholes are put into operation. Reducing the circulating water flow rate when the load is small and increasing it when the load turns large can result in a reduction of >50 % in the fifth year compared to that in the first year.

中深层地源热泵（MGSHP）系统的运行经济性在很大程度上受到多孔中深层井热交换器（MMBHE）运行模式的影响。然而，到目前为止，人们对它的了解还非常有限，远远不够。本研究探讨了多孔中深孔热交换器（MMBHE）不同运行模式对 MGSHP 系统性能的影响，以及全孔运行布置、单孔循环水流量变化和采暖季建筑供热负荷变化等因素。研究分析了循环水温度变化、地下温度场分布和演变、热泵机组 COP、系统性能系数（CSP）、MMBHE 热量提取、MBHE 反向传热深度和耗电量。结果表明，让所有井眼在整个采暖季运行，并在采暖负荷较小时降低循环水流量，在负荷较大时提高循环水流量的运行模式比其他运行模式要好得多。在这种运行模式下，MGSHP 系统的耗电量最低。尽管整个钻孔从地下抽取热量，但钻孔上部有时也会注入热量。通过降低循环水流量可以有效缩短放热段的长度，并随着运行时间的延长而缩短。当所有钻孔都投入运行时，这种缩短效果最为明显。在负荷较小时降低循环水流量，在负荷变大时增加循环水流量，可使第五年的耗水量比第一年减少 50%。

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引用次数: 0

Deep thermal state on the southern margin of the Zhangzhou Basin based on the electrical conductivity model 基于电导率模型的漳州盆地南缘深部热力状态

IF 3.5 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2024-10-30 DOI: 10.1016/j.geothermics.2024.103188

Chaofeng Wu , Dong Xu , Shuojian Yang , Yixin Ye

Exploring the internal spatial and thermal structure of the Zhangzhou Basin is of great scientific significance in understanding the properties of the deep heat sources and the heating mechanism of hot springs in this region. This study estimates the temperature distribution within the upper mantle of the Basin's southern margin using the Arrhenius equation and Hashin-Shtrikman bounds based on a two-dimensional crust-mantle electrical resistivity model. We also employ a layered simulation technique to calculate the crustal temperature distribution using a one-dimensional steady-state heat conduction equation, constrained by the upper mantle's top and ground surface temperatures. This approach displays the characteristics of the longitudinal variations and horizontal inhomogeneities in crust-mantle temperature. Additionally, we estimate the heat flow values within the study area. Our findings reveal that: (i) the upper mantle (at depths of 30 - 50 km) exhibits a temperature range of 700 - 1100 °C, with the presence of local Moho and upper mantle uplifts; (ii) the crustal temperature spans from 21 - 900 °C, with a diminishing influence of the upper mantle uplift area on crustal temperature at shallower depths; (iii) the surface heat flow values derived from our simulations range between 87 and 100 mW/m², averaging at 93.23 mW/m²; (iv) the exploration of dry heat rock in this region is likely to reach a depth of at least 6 km. These results suggest that the genesis of hot springs in the study area is not solely influenced by the heat energy extracted from large-area granitic surrounding rocks during a long transport process, but is also considerably affected by local deep thermal anomalous bodies and deep-large faults.

探索漳州盆地内部空间和热力结构，对了解该地区深部热源性质和温泉加热机制具有重要的科学意义。本研究基于二维地壳-地幔电阻率模型，利用阿伦尼乌斯方程和Hashin-Shtrikman约束估算了盆地南缘上地幔内部的温度分布。我们还采用分层模拟技术，在上地幔顶部和地表温度的约束下，利用一维稳态热传导方程计算地壳温度分布。这种方法显示了地壳-地幔温度纵向变化和横向不均匀的特点。此外，我们还估算了研究区域内的热流值。我们的研究结果表明(i) 上地幔（深度为 30 - 50 千米）的温度范围为 700 - 1100 °C，存在局部莫霍面和上地幔隆起；(ii) 地壳温度范围为 21 - 900 °C，上地幔隆起区对较浅深度地壳温度的影响逐渐减小；(iii) 模拟得出的地表热流值介于 87 - 100 mW/m2 之间，平均值为 93.23 mW/m2；(iv) 该区域干热岩的勘探深度可能至少达到 6 千米。这些结果表明，研究区域的温泉成因并不仅仅受大面积花岗岩围岩在长运移过程中提取的热能的影响，还在很大程度上受到当地深部热异常体和深大断层的影响。

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引用次数: 0

Natural recovery from Fe-oxyhydroxide clogging of a geothermal well in Osaka, Japan 日本大阪地热井氧化铁堵塞的自然恢复

IF 3.5 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2024-10-28 DOI: 10.1016/j.geothermics.2024.103187

Harue Masuda , Yasuhisa Nakaso , Masaki Nakao , Linri Cui

Causes of clogging and the following unique recovering process of an ATES (Aquifer Thermal Energy Storage) system in Maishima (Osaka, Japan) are documented based on the geochemical analyses of groundwater and stagnant water in the system. Fe-oxyhydroxides precipitation clogged screens in an ATES geothermal well during cooling operation. Chemical analyses of waters in the aquifers and plumbing pipes found out that oxidation of dissolved Fe occurred in association with intrusion of ambient air, which was leaked through inadvertently opened air bent valve, into the well. Dual heat-extraction system was installed in the two aquifers of the same wells separated by packers, and the closing occurred in the plumbing pipe installed in the shallow aquifer of one of the thermal wells. This aquifer could not be used as the ATES until when the Fe-oxyhydroxides were naturally dissolved in about a half year after the clogging. Then, the ATES system recovered to be useful. Increasing dissolved Fe with increasing NH₄⁺ and decreasing oxidation–reduction potential indicated that the Fe-oxyhydroxides were dissolved by microbially induced reduction reactions. This case suggests that some clogs can be mitigated without chemical and/or physical treatment, and that monitoring of groundwater chemistry is essential for diagnosing and treating clogs.

根据对该系统中地下水和积水的地球化学分析，记录了位于日本大阪舞岛的 ATES（含水层热能储存）系统的堵塞原因和随后的独特恢复过程。在 ATES 地热井的冷却运行过程中，铁氧氢氧化物沉淀堵塞了滤网。对含水层和管道中的水进行化学分析后发现，溶解铁的氧化与环境空气的侵入有关，而环境空气是通过不慎打开的空气弯管阀泄漏到井中的。同一口井的两个含水层被封隔器隔开，安装了双汲取热量系统，其中一口热力井的浅层含水层的管道发生关闭。该含水层无法用作 ATES，直到堵塞发生约半年后，铁氧氢氧化物自然溶解。之后，ATES 系统才恢复正常。随着 NH4+ 的增加和氧化还原电位的降低，铁的溶解度也在增加，这表明铁氧氢氧化物是通过微生物诱导的还原反应溶解的。这一案例表明，有些堵塞可以在不进行化学和/或物理处理的情况下得到缓解，而监测地下水化学性质对于诊断和处理堵塞至关重要。

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引用次数: 0

Numerical modeling of the Nevados de Chillán fractured geothermal reservoir 奇廉内瓦多斯断裂地热储层的数值建模

IF 3.5 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2024-10-22 DOI: 10.1016/j.geothermics.2024.103181

Isa Oyarzo-Céspedes , Gloria Arancibia , John Browning , Jorge G.F. Crempien , Diego Morata , Valentina Mura , Camila López-Contreras , Santiago Maza

Numerical models can be utilized to understand and anticipate the future behavior of a geothermal reservoir, and hence aid in the development of efficient reservoir engineering strategies. However, as each system has a unique geological context, individual characterization is required. In this research, the Nevados de Chillán Geothermal System (NChGS) in the Southern Volcanic Zone of the Andes is considered. The NChGS is controlled by the geology of the active Nevados de Chillán Volcanic Complex (NChVC) including their basement units (Miocene lavas and volcaniclastic layers from Cura-Mallín Formation and the Miocene, Santa Gertrudis granitoids) as well as the key structural control from crustal scale faults, all of which combine to influence the reservoir characteristics. The presence of faults acts to generate a high secondary permeability which favors the circulation of hydrothermal fluids. Based on previous studies in the NChGS, we designed a thermo-hydraulic model in COMSOL Multiphysics® combining equations of heat transfer and Darcy's law in order to determine the distribution of isotherms and surface heat flux. The boundary conditions of the model were informed by a conceptual model of depth 3 km and width of 6.6 km which considers a highly fractured granitic reservoir, a clay cap behavior of Miocene lavas and volcaniclastic units, and transitional zones between a regional zone and the reservoir. A low-angle reverse fault affecting the clay cap unit was also incorporated into the models. Results indicate convective behavior in the reservoir zone and a surface heat flux of 0.102 W/m² with a local peak up to 0.740 W/m² in the area affected by the low-angle reverse fault zone. The models suggest hydrothermal fluid residence times of around 9–15 thousand years are required to reach a steady-state thermal configuration, which is consistent with the deglaciation age proposed for the NChVC latitude of the complex (c. 10–15 ka). Permeability in the fractured reservoir is one of the most complex parameters to estimate and the most sensitive and hence requires further constraint. Finally, using the volumetric method and the results obtained in this research, we estimate a geothermal potential of 39 ± 1 MWe for the NChGS.

数字模型可用于了解和预测地热储层的未来行为，从而帮助制定高效的储层工程战略。然而，由于每个系统都有其独特的地质背景，因此需要进行单独的特征描述。本研究考虑的是安第斯山脉南部火山区的内瓦多斯德希廉地热系统（NChGS）。内瓦多斯-德-奇廉活跃火山群（Nevados de Chillán Volcanic Complex，NChVC）的地质情况控制着内瓦多斯-德-奇廉地热系统，包括其基底单元（中新世的库拉-马林地层的熔岩和火山碎屑层以及中新世的圣格特鲁迪斯花岗岩），以及来自地壳规模断层的关键结构控制，所有这些因素共同影响着储层的特征。断层的存在产生了高二次渗透率，有利于热液的循环。根据之前对 NChGS 的研究，我们在 COMSOL Multiphysics® 中结合传热方程和达西定律设计了一个热液模型，以确定等温线和表面热通量的分布。该模型的边界条件参考了一个深度为 3 千米、宽度为 6.6 千米的概念模型，该模型考虑了高度断裂的花岗岩储层、由中新世熔岩和火山碎屑岩单元组成的粘土盖层以及区域带与储层之间的过渡带。影响粘土帽单元的低角度逆断层也被纳入模型。结果表明，储层区存在对流行为，地表热通量为 0.102 W/m2，受低角逆断层区影响的局部峰值高达 0.740 W/m2。模型表明，热液停留时间约为 9-15 千年，才能达到稳态热配置，这与为该复合体北西向断裂带纬度提出的脱冰期（约 10-15 ka）相一致。裂缝储层的渗透性是最复杂的估算参数之一，也是最敏感的参数，因此需要进一步的约束。最后，利用容积法和本次研究获得的结果，我们估算出 NChGS 的地热潜力为 39 ± 1 MWe。

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引用次数: 0

Modeling proppant transport and settlement in 3D fracture networks in geothermal reservoirs 地热储层三维裂缝网络中支撑剂迁移和沉降建模

IF 3.5 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2024-10-19 DOI: 10.1016/j.geothermics.2024.103176

Baohua Liu, Dharmendra Kumar, Ahmad Ghassemi

In this paper, we develop an efficient proppant transport model using the Eulerian-Eulerian approach for simulating proppant transport in fractures and 3D fracture networks in geothermal reservoirs. The proposed model accounts for proppant settling, pack/bed formation, bridging/screenout, proppant concentration effect, fracture wall effect, and the transition from Poiseuille flow (fracture channel) to Darcy flow (proppant pack). Notably, the heat transfer process and its impact on proppant transport are also considered—a facet often overlooked in previous proppant transport models. A three-dimensional displacement discontinuity method (3D DDM) that incorporates the stress shadow effect is employed to generate the fracture geometry. The governing equations for slurry flow, proppant transport, and heat transfer are discretized and solved using the finite volume method (FVM). The model is verified against analytical solutions and published experimental data, demonstrating good agreement with these references. To demonstrate the proposed model, we applied it to both low-temperature (depleted hydrocarbon wells) and high-temperature (dry hot rocks) enhanced geothermal systems (EGS). The simulation results highlight the significant influence of reservoir temperature on proppant transport and settlement in a reservoir environment. Heating of the slurry by higher temperature reservoir rocks reduces fluid viscosity and accelerates proppant settling, thereby shortening the transport distance and reducing the coverage area of the proppant. Both ultra-light and micro-proppant are effective in mitigating proppant settlement in enhanced geothermal systems. However, proppant is susceptible to bridging at fracture intersections, where the fracture widths are narrower due to more pronounced stress shadow effects in these areas. Consequently, the use of micro-proppant could offer substantial benefits over ultra-light proppant in enhancing proppant coverage area in enhanced geothermal systems.

本文采用欧拉-欧拉方法开发了一种高效的支撑剂输送模型，用于模拟地热储层裂缝和三维裂缝网络中的支撑剂输送。所提出的模型考虑了支撑剂沉降、包/床形成、架桥/筛出、支撑剂浓度效应、裂缝壁效应以及从波赛流（裂缝通道）到达西流（支撑剂包）的过渡。值得注意的是，该模型还考虑了热传导过程及其对支撑剂输送的影响--这是以前的支撑剂输送模型经常忽略的一个方面。三维位移不连续法（3D DDM）结合了应力阴影效应，用于生成断裂几何形状。泥浆流动、支撑剂输送和传热的控制方程采用有限体积法（FVM）进行离散化和求解。我们根据分析解法和已公布的实验数据对模型进行了验证，结果表明模型与这些参考文献非常吻合。为了证明所提出的模型，我们将其应用于低温（枯竭碳氢化合物井）和高温（干热岩）强化地热系统（EGS）。模拟结果凸显了储层温度对支撑剂在储层环境中的运移和沉降的重要影响。温度较高的储层岩石对泥浆的加热降低了流体粘度，加速了支撑剂的沉降，从而缩短了输送距离，减少了支撑剂的覆盖面积。超轻支撑剂和微支撑剂都能有效缓解强化地热系统中的支撑剂沉降。然而，支撑剂容易在裂缝交汇处架桥，因为这些区域的应力阴影效应更明显，裂缝宽度更窄。因此，与超轻型支撑剂相比，使用微型支撑剂在增强地热系统中提高支撑剂覆盖面积方面具有很大优势。

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引用次数: 0

Three-dimensional electrical imaging of the Aravali-Tural-Rajwadi geothermal system, West Coast of India 印度西海岸阿拉瓦利-图拉尔-拉杰瓦迪地热系统的三维电气成像

IF 3.5 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2024-10-18 DOI: 10.1016/j.geothermics.2024.103185

Khasi Raju , Vasu Deshmukh , P.V. Vijaya Kumar , P.B.V. Subba Rao , A.K. Singh

The West Coast geothermal system is a prominent geothermal region in the Indian subcontinent, and understanding its geothermal reservoirs is crucial for societal benefits. In the present study, we employed 3D modeling of Audio and broad-band Magnetotelluric (AMT & MT) data for the first time in the West Coast geothermal region, covering the Aravali, Tural, and Rajwadi geothermal zones, to gain insights into the evolution of geothermal zone and geothermal reservoir characteristics. The 3D inversion results revealed the presence of a thin layer of granitic crustal layer, which decreases in thickness towards the west. The rifting process along the western continental margin of India has introduced magmatism (underplated) to the crustal level, which manifests as a moderate conductivity (100–500 Ωm) layer in shallow depths (∼10 km). The cooling and solidification of underplating materials contribute to the heat flux along the West Coast geothermal zone (WCGZ). The circulation of meteoric water within the deep layers gets heated up by these mantle materials and is ejected along the fracture and fault zones that appear as hot springs. Considering a thin crustal layer, a shallow Moho, and an upwelling asthenosphere along the west coast, the WCGZ is considered a convective geothermal play type. This study enhances an understanding of the WCGZ geothermal potential and geological processes, which can have significant implications for harnessing this valuable energy resource.

西海岸地热系统是印度次大陆的一个重要地热区，了解其地热储层对社会效益至关重要。在本研究中，我们首次在西海岸地热区（涵盖阿拉瓦里、图拉勒和拉杰瓦迪地热区）采用了音频和宽带磁触伦（AMT & MT）数据的三维建模，以深入了解地热区的演变和地热储层的特征。三维反演结果显示存在一层薄的花岗岩地壳层，厚度向西递减。印度西部大陆边缘的断裂过程在地壳层中引入了岩浆活动（下伏），在浅层（10 千米以下）表现为中等导电率（100-500 Ωm）层。底板材料的冷却和凝固促进了西海岸地热区（WCGZ）的热通量。深层中的流星水循环被这些地幔物质加热，沿断裂带和断层带喷出，形成温泉。考虑到地壳层较薄、莫霍河较浅以及西海岸沿岸的上涌岩浆层，WCGZ 被认为是一种对流地热作用类型。这项研究加深了人们对 WCGZ 地热潜力和地质过程的了解，对利用这一宝贵的能源资源具有重大意义。

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引用次数: 0