Ceboruco Volcano is a Quaternary stratovolcano located in Nayarit near the Trans-Mexican Volcanic Belt western limit. It is one of the most active in the region and the only volcano in Nayarit with historically documented eruptions, the last one between 1870 and 1875. Currently, seismicity and fumarolic activity suggest hydrothermal activity. To study the geoelectrical setting at Ceboruco Volcano and its hydrothermal system, a magnetotelluric exploration campaign was carried out in November 2016, establishing 24 measuring stations at the caldera, and foothills of the volcanic edifice. Three broadband instruments were used in the sampling frequency range of 32,768–128 Hz. Recorded time series were processed to determine the MT transfer functions using a robust algorithm and consider the remote-reference station technique. Dimensionality analysis based on the phase tensor determined a shallow 1D geoelectrical structure at periods shorter than 1 s, while a 3D formation was defined at longer periods. To approximate the Ceboruco Volcano substructure, the 3D inversion of magnetotelluric data was carried out. 3D modeling revealed surficial resistivity regions that were related to young volcanic deposits. A relative conductor (10–30 Ωm) was also associated with the shallow regional aquifer. The two most intriguing results of 3D inversion were one uppermost conductive region (~1 Ωm) that established characteristics, resistivity, position, and thickness related to a clay alteration minerals zone. The other one (2–5 Ωm) corresponds to a conductive area broadening and fading with depth, centered slightly to the west of the summit at Ceboruco Volcano. The preferred interpretation of this geoelectrical feature was an envelope of high-temperature fluids, convection of steam, and brines, and they are interacting with the host-rock and surficial groundwater. This geoelectrical feature extends in depth, suggesting a permeable region at the Trans-Mexican Volcanic Belt basement that may be targeted for in-depth geothermal exploration. The geoelectrical setting identified in this study provides information that contributes to reducing uncertainty about the geological, geophysical, and hydrogeological conceptual models at Ceboruco Volcano geothermal system.

塞波鲁科火山是第四纪层状火山，位于纳亚里特，靠近跨墨西哥火山带西部边界。它是该地区最活跃的火山之一，也是纳亚里特唯一有历史记载喷发的火山，最后一次喷发发生在 1870 年至 1875 年之间。目前，地震活动和喷气火山活动表明存在热液活动。为了研究塞波鲁科火山及其热液系统的地电环境，2016 年 11 月开展了大地电磁勘探活动，在火山口和火山大厦的山麓建立了 24 个测量站。在 32,768–128 Hz 的采样频率范围内使用了三种宽带仪器。处理记录的时间序列以确定使用稳健算法的 MT 传递函数并考虑远程参考站技术。基于相位张量的维数分析在短于 1 s 的周期内确定了浅层 1D 地电结构，而在更长的周期内定义了 3D 地层。为了近似 Ceboruco 火山子结构，进行了大地电磁数据的 3D 反演。3D 建模揭示了与年轻火山沉积物相关的地表电阻率区域。一个相对导体 (10-30 Ωm) 也与浅层区域含水层有关。3D 反演的两个最有趣的结果是一个最上面的导电区域 (~1 Ωm)，它确定了与粘土蚀变矿物带相关的特征、电阻率、位置和厚度。另一个 (2–5 Ωm) 对应于随深度扩大和衰减的导电区域，其中心略微位于 Ceboruco 火山的山顶以西。对该地电特征的首选解释是高温流体、蒸汽对流和盐水的包层，它们与主岩和地表地下水相互作用。这种地电特征在深度上延伸，表明跨墨西哥火山带基底的可渗透区域可能是深入地热勘探的目标。本研究中确定的地电环境提供的信息有助于减少 Ceboruco 火山地热系统的地质、地球物理和水文地质概念模型的不确定性。表明跨墨西哥火山带基底的可渗透区域可能是深入地热勘探的目标。本研究中确定的地电环境提供的信息有助于减少 Ceboruco 火山地热系统的地质、地球物理和水文地质概念模型的不确定性。表明跨墨西哥火山带基底的可渗透区域可能是深入地热勘探的目标。本研究中确定的地电环境提供的信息有助于减少 Ceboruco 火山地热系统的地质、地球物理和水文地质概念模型的不确定性。