The role of geophysics in enhancing mine planning decision-making in small-scale mining

Small-scale mining usually operates under high geological uncertainty conditions. This turns mine planning into a complex and sometimes inaccurate task, resulting in low productivity and substantial variability in the quantity and quality of the mineral products. This research demonstrates how the application of a novel methodology that relies on traditional and low-cost geophysical methods can contribute to mine planning in small-scale mining. A combination of resistivity and induced polarization methods is applied to enhance mine planning decision-making in three small-scale mining operations. This approach allows for the acquisition of new data regarding local geological settings, supporting geological modelling and enhancing decision-making processes for mine planning in a timely and low-cost fashion. The results indicate time savings of up to 77% and cost reductions of up to 94% as compared with conventional methods, contributing to more effective mine planning and, ultimately, improving sustainability in small-scale mining.

If the approach presented in Martins et al (2016) and Martins (2017, Thesis) is new the authors have to present it within the text. This is missing . Over all the work has no new methodology in its presnt form. The authors have to re-write the text making clear what is new and what is the real innovation claimed. In addition I strongly suggest to inlude in the revised text a clear condtribution of how the geophysical uncertainty involved in the reduction of geological one. Furthermore, the references have to include some more recent ones and the existing part has to updated with some references in the geophysical field from International mainstream journals. Till then the work is not suitable for publication.
Decision letter (RSOS-200384.R0) We hope you are keeping well at this difficult and unusual time. We continue to value your support of the journal in these challenging circumstances. If Royal Society Open Science can assist you at all, please don't hesitate to let us know at the email address below.
Dear Mr Tichauer, The editors assigned to your paper ("THE ROLE OF GEOPHYSICS IN ENHANCING MINE PLANNING DECISION-MAKING IN SMALL-SCALE MINING") have now received comments from reviewers. We would like you to revise your paper in accordance with the referee and Associate Editor suggestions which can be found below (not including confidential reports to the Editor). Please note this decision does not guarantee eventual acceptance.
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Once again, thank you for submitting your manuscript to Royal Society Open Science and I look forward to receiving your revision. If you have any questions at all, please do not hesitate to get in touch. Comments to the Author(s) This manuscript presents a novel application of a geophysical methodology on three case studies and demonstrates that this approach can reduce exploration cost in small scale mines. The original geophysical data from two sites (limestone and manganese mines) which were acquired using electrical resistivity methods (Vertical Electrical Sounding (VES) and the Electrical Resistivity Tomography (ERT) techniques), have been presented in another publication (Martins A.C., Terenci E.R., Tomi G.D., Tichauer R.M. 2016. Impact of Geophysics in Small-Scale Mining. J Remote Sensing & GIS, 5, 172). For these two case studies there is a significant overlap between the manuscript and the above mentioned paper regarding the text. The manuscript needs major revision to reduce this overlap. The authors claim that they used the Induced Polarization (IP) method. There is no description of this method in "2.2 Geophysical methods". It is suggested to describe shortly the principle of IP method mentioning its usefulness in mining exploration or in delineating these particular deposits. Additionally, describe an IP survey from a single site (eg the limestone mine) including the experiment parameters, the employed instrument, the data processing techniques, the employed software and figures with selected resistivity and chargeability sections. It is suggested to include figures with selected ERT section(s) and/or VES geoelectrical curves for the gold mine case study. Some references are not properly written and/or are incomplete. English needs improvement. More specific comments are attached in a file (Specific comments.pdf) The manuscript needs major revision not only to reduce the overlap but also regarding the above mentioned comments.

Reviewer: 2
Comments to the Author(s) The work in its present form is not suitable for pubication and a major revision and not rejection is suggested in order to give an opportunity to authors to modify (if possible) their work. The style of the work is suitable to a technical report or a Thesis and not to a scientific paper. The geophysical methods used/proposed are very old tratidional geophysical methods and does not present any new methodological information nor an applied innovation. In the abstract a "novel application" claimed. I can not see such in all over the text, even if the authors claim such in many parts of the text (see page 4, line 10-11). If the approach presented in Martins et al (2016) and Martins (2017, Thesis) is new the authors have to present it within the text. This is missing . Over all the work has no new methodology in its presnt form. The authors have to re-write the text making clear what is new and what is the real innovation claimed. In addition I strongly suggest to inlude in the revised text a clear condtribution of how the geophysical uncertainty involved in the reduction of geological one. Furthermore, the references have to include some more recent ones and the existing part has to updated with some references in the geophysical field from International mainstream journals. Till then the work is not suitable for publication.

Decision letter (RSOS-200384.R1)
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Dear Mr Tichauer, It is a pleasure to accept your manuscript entitled "THE ROLE OF GEOPHYSICS IN ENHANCING MINE PLANNING DECISION-MAKING IN SMALL-SCALE MINING" in its current form for publication in Royal Society Open Science.
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Thank you for your fine contribution. On behalf of the Editors of Royal Society Open Science, we look forward to your continued contributions to the Journal. Most VES surveys showed four layers, as observed in Table 4. The first layer was interpreted as superficial soil (low to medium resistivity), the second, unsaturated altered rock (high resistivity and medium chargeability), the third, saturated altered rock (low and medium resistivity and low chargeability), and the fourth, gneiss (high resistivity).
Follow the same for the other two case studies. / Most VES surveys showed four layers, as observed on Table 4. The first layer was interpreted as superficial soil (low to medium resistivity), the second, unsaturated altered rock (high resistivity and medium chargeability), the third, saturated altered rock (low and medium resistivity and low chargeability), and the fourth, gneiss (high resistivity). 28 The utilisation of VES and EP in the gold project, with the support of auger assays, allowed for the elaboration of a geological model for the mineralised soil layer ...
Can you include a figure with a resistivity and/or chargeability section in order to support this statement?

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The time reduction was calculated as 77% compared with a drilling campaign.