Shallow and Deep Electric Structures in the Tolhuaca Geothermal System (S. Chile) Investigated by Magnetotellurics

Round 1

Reviewer 1 Report

This paper is aimed to infer the resistivity structure of Tolhuaca volcano by three-dimensional (3D) inversion of magnetotelluric (MT) data. The topic of the paper is of wide interest for volcanology community and deserves publication after minor revisions. Data is well presented as well as the methods. I’m not an expert of MT data inversion and thus, I hope that others reviewers can provide a critical revision of the methods section. My expertise is about the interpretation of MT and in general of resistivity data, and this is the reason why I focused my comments and suggestions on the interpretation of resistivity anomalies. As regards, since the investigated zone is affected by very high geothermal gradients, I suggest to the Authors to assess how this thermal anomaly can affect the distribution of different resistivity. In general, I agree with the interpretation of the Authors about the presence of a shallow cap-rock and the zone where magma resides, although the Authors can implement their results. I attached very few comments about this. 

Best regards

 

Comments for author File: Comments.pdf

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

1. Through 3D MT imaging, the manuscript has established the dynamic model of the volcanic geothermal system in the study area, and given the deep high conductivity areas C1, C2 and C3. Among them, C1 high conductivity anomaly features prominently, and C2 and C3 also have clearly identified high conductivity anomaly.

2. Combined with borehole temperature measurement data and MT inversion of electrical structure distribution, the manuscript gives the migration path of shallow geothermal flow in the study area.

3. Due to the limitation of actual conditions, MT measuring points in the study area are unevenly distributed, especially the right side of C1 high conductivity area is far from MT measuring point. It is hoped that the blank area of MT measurement can be appropriately supplemented in the next step to establish a more precise and reliable three-dimensional geoelectric model.

Author Response

We appreciate your comments. As we have not received any suggestions from you, the manuscript has been improved according to the suggestions of reviewer 1.