Ore Genesis at the Jinchang Gold–Copper Deposit in Heilongjiang Province, Northeastern China: Evidence from Geology, Fluid Inclusions, and H–O–S Isotopes
Round 1
Reviewer 1 Report
Although this paper is the result of a competent and thorough study, I do find a serious problem with the material in section 5.1, lines 382-391. It is concluded that solid inclusions of pyrite and chalcopyrite are typical of melt inclusions and formed at the magmatic stage. In fact, such inclusion in FIs are common in porphyry deposits; one has only to refer to Roedder (1984, chapter 15). There is ample data to show that copper and iron contents in porphyry FIs are adequate to produce true daughter products, i.e. minerals formed by precipitation from the solution in the FIs. As well, as illustrated by Bodnar (2003) solid inclusions, which he called “accidental inclusions”, may form by enclosure of a solid during formation of an FI. In any event, the temperatures determined in this study are well below the magmatic stage. As well and most importantly, the inclusions are in hydrothermal quartz derived from solutions that were originally of magmatic origin, but resulted in post-magmatic crystallization of quartz. Figure 8 is related to the idea present, but most of the figure does not relate to this study and should be deleted.
There are problems with some of the figures, in particular Figures 4 and 5. The many photographs in Figure 4 are poorly executed and most do not show anything of great significance. As well, they are not discussed in the text. In Figure 5, there is nothing significant about the common mineral illustrated, and there is no discussion of them in the text. I do find that in 5a and b that it is stated that sphalerite is replacing pyrite and pyrite is replacing sphalerite, respectively. I see no evidence for replacement, and all that one can say is that in A there are inclusions of sphalerite in pyrite and in B that there are inclusions of pyrite in sphalerite. Neither occurrence is of any great significance. (Sorry, but these sorts of statements have always bothered me.) Finally, Figure 10A is more than 50 years old and is unnecessary in view of the discussion in the text.
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Below I have made comments about specific relatively lesser point in the text, most of which can be readily addressed. Finally, I have made some suggestions that the authors may wish to consider. I believe that they would add to the paper.
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Abstract - Quite adequate, except for two points. Although this is a gold deposit, gold is nowhere mentioned in the abstract. It should be noted that gold occurs in all three stages and which stage is the major gold-producing stage. Surprisingly, although the study is directed at determining the type of deposit concerned, the conclusion that it is a porphyry type deposit is not mentioned. (More could be added if my suggestions are heeded.
lines 30-32: I would suggest that Heilongjiang Province is not of importance as a keyword, but that porphyry deposit is.
line 54: Reference [12] seems to be incorrect as it refers to porphyry deposits, not orogenic and it should say orogenic gold.
line 68: Replace “belongs to” with “is within” [English].
line 72 (Figure 1 legend: In the legend, the faults F1: Mudanjiang Fault etc. are not labeled on the map.
lines 75-76: The Laoheishan depression and Taipingling uplift are not indicated on Figure 1 although other structural features are.
line 95: The caption should add “ Ages of igneous bodies are indicated.”
line 112: Replace “ore rock” with “host rock of the ore”. [English]
line 143: It is not clear to what “No. 18” refers. Needs to be consistent with designations previously used.
line 188: Add (Fig. 3) to end of caption.
line 203: After “. . . ice,” add “using the equation of Bodnar [27].” Otherwise, the statement is really rather elementary.
line 219: Insert comma after “(VCDT)”.
line 270 (Table 1): In the heading of the table, abbreviate “Number” with “No.”; then close up space on the left so that host mineral labels are properly divided. Abbreviate “gas-liquid” with “V-L”.
line 360: The meaning of “lithologic boundaries” is unclear.
line 407: A suggestion. Could add that parallelism with basinal water lines is further evidence of mixing.
lines 444 and 446: “thorogenic” and “uranogenic” are not words so far as I know. Some other expression is needed. As well, “unradiogenic” should be replaced by “non-radiogenic”. [English]
line 459: Delete entire line. It is obvious from the heading of the section.
line 473 (Figure 12b): The meaning term “Hydrotherm” is unknown to me.
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I have a suggestion that you may wish to consider. I believe that it would serve to make your paper more interesting. You have fairly convincingly established that the deposit is a porphyry-type deposit; however, what type of porphyry deposit is it? One cannot determine from what is given whether it is a gold porphyry or a copper-gold porphyry. What is needed is the tenor of copper and/or the Cu/Au ratio that has been employed by some workers. Of course, other factors such as the nature of the alteration, the type of igneous host, and other factors need to be considered as well. I note that reference [12] states that it is a gold porphyry. This could be stated with a little elaboration.
Comments for author File: 
Comments.pdf
Author Response
Respected reviewer:
I appreciate your time in reviewing my manuscript so soon. Your opinion is very important and precious to me. The paper has been carefully thinking and modified. There are some detailed changes as follows:
1. Line 418-442 – 5.2. Source and evolution of the hydrothermal fluid.
Thanks for your advice. The sentences were re-described. And add more information to the fluid evolution and melt-fluid inclusion. We agree that FIs with solid inclusions of pyrite and chalcopyrite are common in porphyry deposits. But fluid–melt inclusions the transition state between fluid inclusion and melt inclusion. Both melt (silicate) and fluid phases occur in the fluid–melt inclusion.
2. Figure 9
Deleted the meaningless part of the figure.
3. Figures 4 and 5
Deleted meaningless images. The caption has been modified.
4. Figure 11A
The figure has been deleted.
5. Abstract
Line 16-18: Add“Gold was deposited during all three stages and stage 1 was the major gold-producing stage. Copper is associated with the mineralization but has low economic value”.
Line 34-35: Add “The Jinchang deposit is a typical gold-rich gold–copper porphyry deposit.”
6. Line 36-37: Change the “Heilongjiang Province” to “porphyry deposit” in the Keywords.
7. Line 62: Change the Reference [12].
8. Line 75: Replace “belongs to” with “is within”.
9. Figure 1
The faults (F1-F6) are labeled on the Figure 1. The Laoheishan graben and Taipingling horst are indicated on Figure 1.
10 Line 102-103: Add “(ages of igneous rocks are annotated on the map).” to the caption.
11.Line 127: Replace “ore rock” with “ore host rock”.
12. Line 117: Unified the “No. J-18” to “No. 18”.
13. Line 221: Add (Fig. 3) to the end of caption.
14. Line 233: Add “using the equation of Bodnar [27].”
15. Line 254: Insert comma after “(VCDT)”.
16. Table 1
Abbreviate “Number” with “No.”; Abbreviate “gas-liquid” with “V-L”.
17. Line 399: Modify “lithologic boundaries” to “lithofacies boundaries”.
18. Line 464-465: Add“The trend of the data parallel to the basinal water lines provides further evidence of mixing”.
19.Lines 506 and 507: “thorogenic” and “uranogenic” .
Here are the reference about “thorogenic” and “uranogenic”.
Amov, B. G. . (1983). Evolution of uranogenic and thorogenic lead, 1. a dynamic model of continuous isotopic evolution. Earth & Planetary Science Letters, 65(1), 61-74.
20. Line 521: Delete “Below, we propose a genetic model to explain the formation of the Jinchang Deposit”.
21.Figure 13B
Modify “Hydrotherm” to “Pipe”.
22. Established that the deposit is a gold-rich Au-Cu porphyry deposit. The content of gold and copper is described in Introduction. The type of igneous host is described in 2.4. Timing of metallogenesis.
23. Updated references.
24.The manuscript has undergone extensive English editing and check by native English speakers. The certification of English editing is in in the attachment.
Thanks again for your guidance and valuable suggestions. If you have any queries, please don’t hesitate to contact me through Manuscript Tracking System.
Best regards.
Shunda Li
Author Response File: Author Response.pdf
Reviewer 2 Report
This manuscript requires a lot of formal editing to bring it to the level for publication in Minerals. The authors should work with someone closely to help enhance the scientific communication of this important contribution. Very general statements (hydrothermal deposits are the ...) through to "graphitic" granite (wrong statements) tell reviewers these authors need to read a lot more critically others research papers, then use that to build their manuscript for publication. There is a lot of good data here to do that. The Discussion of the implications of this FLINCS & isotope study should be more rigorous and the Conclusions should be much more detailed with important conclusions included within the Conclusions section. It would be good to see this important work published in modified form.
Author Response
Respected reviewer:
I appreciate your time in reviewing my manuscript so soon. Your opinion is very important and precious to me. The paper has been carefully thinking and modified. There are some detailed changes as follows:
1.The manuscript has undergone extensive English editing and check by native English speakers. The certification of English editing is in the attachment.
2. Discussion
Thanks for your advice. This section was re-described. And add more information to the FIs and isotope analysis.
3. Conclusions
The conclusions were re-described and more detailed.
The revisions are detailed in the manuscript.
Thanks again for your guidance and valuable suggestions. If you have any queries, please don’t hesitate to contact me through Manuscript Tracking System.
Best regards.
Shunda Li
Author Response File: Author Response.pdf
Reviewer 3 Report
This is an interesting study in which the authors examined fluid inclusions from a suspected intrusion-related gold deposit, but also asses the fluid model using stable isotopes.
I would suggest a few lines from Heinrich and Candella (2014), and Bruce Yardley's (2005) reviews to bolster both the introduction and fluid model section.
The porphyry model is herein chosen but explanation with respect to the Au type or Cu-Au is missing. Note that gold porphyry is commonly interpreted as related to alkaline magmatic trend. Please explain …
Also, in porphyry systems hydrolysis reactions produce alterations in & around the ore body, but this is not well described, so a note and(or) a sketch on that would help.
The mineralization is related to exsolved magmatic fluids from the associated granodiorite intrusion. In fig. 8, such exsolution occurs at 1.5 kbars whereas the three main metallogenetic stages are emplaced in the epithermal system at 0.2 kbars. So, how do you explain that the granodiorite at the origin of the mineralization occurs 300-400 m below the orebody in fig. 3?
In addition, the fluids transporting silica, sulphur, gold, and base-metals would be exsolving at high T and evolving down a thermal gradient to low T. Given that, Cl-OH complexing typically dominates those metals. The recent reviews from Fontboté et al. (2017), and Kouzmanov and Pokrovski (2012) would help to understand the magmatic-hydrothermal processes. It would be best as well, to bolster the quartz solubility a bit more with further references (Fournier, 1999; Kouzmanov and Pokrovski, 2012). The paper of Tuduri et al., (2018) would help for this.
Fluid boiling appears as an important processes at the origin of the deposit. Does mineral features have been observed to support such an assumption? Literature is abundant on it, e.g. Chauvet et al., 2006.
The breccia word is frequently used instead of stockwerk that are common in porphyry systems. I agree. However, some structures are interpreted as pipe but description are poor about that. Please explain. Note that this pipe are absents in fig 3.
Why the breccia-pipe model is not proposed in the paper? The figure 12B suggests it.
The most important points concern the results of the stable isotope study. The trend from stages 1 to 3 is clear but does not represent a clear trend towards the meteoric water lines. Authors need to bolster that section. One may wonder whether the analytical condition of H by decrepitation generates fractionation of H isotopes and if secondary inclusions are involved during decrepitation processes? Does heating process help to vaporize the lightest element and thus decreases the dD?
I leave that up to the authors to decide how to proceed.
Chauvet, A.; Bailly, L.; André, A.-S.; Monié, P.; Cassard, D.; Tajada, F.; Vargas, J.; Tuduri, J. Internal vein texture and vein evolution of the epithermal Shila-Paula district, southern Peru. Miner. Deposita 2006, 41, 387-410.
Fontboté, L.; Kouzmanov, K.; Chiaradia, M.; Pokrovski, G.S. Sulfide minerals in hydrothermal deposits. Elements 2017, 13, 97-103.
Fournier, R.O. Hydrothermal processes related to movement of fluid from plastic into brittle rock in the magmatic-epithermal environment. Econ. Geol. 1999, 94, 1193-1211.
Heinrich, C.A.; Candela, P.A. 13.1 - Fluids and Ore Formation in the Earth's Crust A2 - Holland, Heinrich D. In Treatise on Geochemistry (Second Edition), Turekian, K.K., Ed. Elsevier: Oxford, 2014; http://dx.doi.org/10.1016/B978-0-08-095975-7.01101-3pp. 1-28.
Kouzmanov, K.; Pokrovski, G.S. Hydrothermal controls on metal distribution in porphyry Cu (-Mo-Au) systems. In Geology and genesis of major copper deposits and districts of the world: a tribute to Richard H. Sillitoe, Hedenquist, J.W., Harris, M., Camus, F., Eds. Special Publications of the Society of Economic Geologists: 2012; Vol. 16, pp. 573-618.
Tuduri, J.; Chauvet, A.; Barbanson, L.; Labriki, M.; Dubois, M.; Trapy, P.-H.; Lahfid, A.; Poujol, M.; Melleton, J.; Badra, L., et al. Structural control, magmatic-hydrothermal evolution and formation of hornfels-hosted, intrusion-related gold deposits: Insight from the Thaghassa deposit in Eastern Anti-Atlas, Morocco. Ore Geol. Rev. 2018, 97, 171-198, doi:https://doi.org/10.1016/j.oregeorev.2018.04.023.
Yardley, B.W. 100th Anniversary Special Paper: metal concentrations in crustal fluids and their relationship to ore formation. Econ. Geol. 2005, 100, 613-632.
There are numerous issues with English. This includes in the figures as well. Phraseology is problematic in places, then the manuscript needs to be re-read by a native English speaker.
Some comments:
Line 38 – add a reference related to fluids in orogenic systems.
Line 40 - add a reference related to fluids in porphyry and epithermal systems. Note that epithermal systems may be of HS, IS or LS states implying drastic change in fluid compositions.
Line 41 - add a reference related to fluids in MVTsystems.
Line 50 – We need to have details on these pioneer FI works. Do you have Raman data?
Lines 69-71 – the sentence is unclear and needs reference(s).
Figure 1:
Legend – granitoids and not granitiods
Fig1A – Map of China with location of fig14B is more suitable
Where is the fig2 close-up view in fig1A?
Line 76 – uplift : do you mean horst ? change in figure 1B. Where is the Laoheishan depression (graben) in figure 1B?
Lines 79-81 – Is there difference between age of emplacement and geochemical features?
Lines 81-84 – unclear : does the Mesozoic volcanic rocks are undeformed?
Lines 86-88 – these lithologies are not on fig2.
Lines 89 – E-W and N-S faults do not appear as dominant direction on figure 2. Please provide stereonets.
Line 92 – there is no granodiorite on map (fig 2).
Figure 2:
No reference in the title of the map.
Line 96 - tectono-magmatic.
Line 99 - Graphic granite and not graphitic.
Line 100 – In what consists the Jurassic stock on fig 3?
Figure 1:
Legend – maybe add the age of each intrusives?
No reference in the title of the map.
Where are the ring structure and faults on these cross-section?
Line 112 – Why cement and not matrix ?
Line 114 – give the proportions of sulfide and alteration minerals in the matrix.
Line 115 – 3.86 m wide is very precise.
Line 126 – Azurite is typically a supergene phase. Please provide references or evidences to explain it may become a hypogene crystal. Add a paragenetic diagram to the text.
Line 148 – Paragenetic sequences …. Where is the diagram?
Line 156 – Use abbreviations of Whitney and Evans for minerals.
Whitney, D.L.; Evans, B.W. Abbreviations for names of rock-forming minerals. Am. Mineral. 2010, 95, 185-187, doi:10.2138/am.2010.3371.
Lines 200-205 – Do you use the FIA methodology of Goldstein and Reynolds ?
Goldstein, R.H.; Reynolds, T.J. Systematics of fluid inclusions in diagenetic minerals; Society for Sedimentary Geology: 1994; Vol. 31, pp. 199.
Lines 233-234 – I suggest the authors use VL or V for vapor-rich inclusions and LV to Lv for liquid-rich inclusions.
Figure 8:
No reference in the title of the diagram.
Lines 382-383 – typical of melt inclusion .. Melt is glass … in what the occurrence of daughter minerals is typical of fluid-melt inclusion? Give references.
Figure 12:
No fault and no ring structure in the model. What is hydrotherm?
How do you explain flat vein at depth and more steep close to the surface?
Line 535 – porphyry and nor prophyry.
Author Response
Respected reviewer:
I appreciate your time in reviewing my manuscript so soon. Your opinion is very important and precious to me. The paper has been carefully thinking and modified. There are some detailed changes as follows:
1.The manuscript has undergone extensive English editing and check by native English speakers. The certification of English editing is in in the attachment.
2. Introduction and Discussion
Thanks for your advice. The sentences were re-described. And add more information to the introduction and fluid model section.
3. Established that the deposit is a gold-rich Au-Cu porphyry deposit. The type of igneous host is described in 2.4. Timing of metallogenesis.
4. The alterations around the ore body were re-described. And add new sketches (Fig.3B-D).
5. Deleted the wrong parts in the Figure 9.
6. Line 418-445: Add more information from recent research to the magmatic-hydrothermal processes.
7. Fluid boiling
We are sorry about that there are no obvious boiling mineral features, such as coexistence of adularia and platy calcite observed in the samples. But the FIs features indicate fluid boiling.
8. Line 123-128: Breccia pipes are described in more detail. The pipe (J-1) is labeled on the Figure 3.
9. Oxygen and hydrogen isotope analysis
The analysis of isotopes was carried out in a closed environment. External heating and the decrepitation of inclusions did not affect the isotope measurements. The analyzed samples were carefully selected, and the primary inclusions were dominant in the quartz grains, whereas secondary inclusions were minor
10. Add new references where are needed.
11. Line 57: I am so sorry about that we do not have Raman data.
12. Figure 1: Modify “granitiods” to “granitoids”; Add the location of Fig1B in Fig 1A; Add the close-up view of Fig.2 in Fig.1A; Modify “uplift” to “horst”; Modify “depression” to “graben”; The Laoheishan graben is labeled on the Figure 1; Add the age of each intrusive in Figure 1.
13. Lines 91: Deleted the word “undeformed” which may misleading.
14. Line 93-94: Modify the legend “Pyroclasic” to “Tuntianying Group” on Fig 2.
The lithology of Tuntianying Group include andesite, basaltic andesite, andesitic porphyry, and tuff.
15. Line 96-97: Modify the sentence to “The dominant structures are NW–SE- and NE–SW-trending faults, along with secondary E–W- and N–S-trending faults.”
16. Line 102: There is no granodiorite on map due to the granodiorite is concealed underground.
17. Line 104: Modify “tectonic-magmatic” to “Tectonomagmatism”.
18. Line 107: Modify “graphitic granite” to “graphic granite”.
19. Line 108-109 – In what consists the Jurassic stock on fig 3?
Early Jurassic granite stock in the southern part of the deposit.
20. Fig.3
Add the ring structure and faults on the cross-section.
21. Line 128: Modify “cement” to “matrix”.
22. Line 130-131: Add the proportions of sulfide and alteration minerals in the matrix.
23. The thickness of the ore body is accurate to one decimal place.
24. Add a new paragenetic diagram (Fig. 6). Azurite, covellite and malachite all belong to supergene phase.
25. Fig. 5
Modify “Mot” to “Mol” and “Gl” to “Au”, using abbreviations of Whitney and Evans for minerals.
26. Line 233: Add the FIA methodology of Goldstein and Reynolds
27. Use V for vapor-rich inclusions and LV for liquid-rich inclusions.
28. Figure 13.
Add faults in the model; Modify “hydrotherm” to “pipe”; Modify the shape of the disseminated ore body; The shallow ore bodies are also part of the faults and occur in these favorable spaces. The shallow vein orebody is controlled by faults and the orebody is steep. The deep disseminated ore bodies are formed in the contact zone between the granodiorite and the strata. The shape of the ore body is like a layered.
Thanks again for your guidance and valuable suggestions. If you have any queries, please don’t hesitate to contact me through Manuscript Tracking System.
Best regards.
Shunda Li
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
I see that nearly all of the minor corrections I had pointed out in my previous review have been incorporated in the current version of the paper. However, with more time for examination of the paper, I find a few additional minor problems, a few a bit more significant and one remaining major one.
References – I find some inconsistencies in this section: 1) failure to abbreviate some of the titles of journals, according to instructions to the authors; 2) inclusion of issue numbers of journal in some cases but not in others; and 3) enclosing dates of references in parentheses in some cases, but not in others.
Table 1 – I had suggested using the heading “No.” for “Number” and “V-L” for “gas-liquid” so that the whole columns could be shifted so as to make space such that the awkward word divides in the “Host mineral” could be repaired. For example, “arsenopy – rite” and “chalcopyr – ite”. I hope that my intention is clear now.
Figure 7 (current version) – Photos are well done, but really too small, especially in the cases where one would like to see the solid phases. Can they be enlarged and rearranged, say in two rows of photos? Also, the indication “primary” and the lines hardly show in part C.
Figure 9 (current version) – Your Figure 9 seems to be a copy of Figure 5 from Redmond et al. (2004); however, except for the upper one-third of the figure, it does not apply to your study and its results. I suggest that you use this portion of the figure, eliminating the lines of high NaCl concentration from the diagram.
Line 399 (original line 360) – I think that either “lithologic” or even worse, “lithfacies’ are confusing and unnecessary . Just say “distinct boundaries”. That is perfectly clear in this context.
Lines 506-507 (original version) - These are new terms to me, but I suppose there is enough precedence for their use.
Line 506 (current version) – Replace “unradiogenic” with “non-radiogenic”
Line 592 (current version) – Cl and Br are not capitalized.
Lines 442-447 (current version) – This section is problematical and should be greatly shortened to a mention of the previous work in the Chinese literature that has been cited. Although the process described is a possibility, there is nothing presented here to provide any evidence that it has occurred. No data have been present in this paper to support the interpretation of melt inclusions. The rather didactic discussion presented is not relevant to the thrust of the paper and does not add to it.
Comments for author File: Comments.pdf
Author Response
Dear reviewer,
Thank you very much for your comments on our manuscript. All comments are valuable and helpful for improving the quality of the paper. We have fully considered the comments and thoroughly revised the paper. There are some detailed changes as follows:
1. References have been modified to a consistent format.
2. The format of Table 1 has been modified.
3. Figure 7 has been enlarged and rearranged.
4. Figure 9 has been modified.
5. Line 377: “lithfacies” has been deleted.
6. Line 472: Replaced “unradiogenic” with “uranogenic”. Sorry, it’s my spelling mistake.
7. Line 573: Replaced “Na-cl-br” with “Na-Cl-Br”.
8. Line 398-419: This section has been greatly shortened.
Thanks again for your guidance and valuable suggestions. If you have any queries, please don’t hesitate to contact me through Manuscript Tracking System.
Best regards.
Shunda Li
Author Response File: Author Response.pdf
Reviewer 2 Report
Separate supergene from hypogene (stages 1-3) in the presentation of the ore minerals as you do in the table.
Fix the name to Supergene in the table.
Add Drummond and Ohmoto (1985) reference to explain the metal saturation implications of boiling.
Add Burnham (1985) on implications of boiling to explosive brecciation.
Both those papers are in Economic Geology.
Other aspects are noted in the highlights on the pdf.
Author Response
Dear reviewer,
Thank you very much for your comments on our manuscript. All comments are valuable and helpful for improving the quality of the paper. We have fully considered the comments and thoroughly revised the paper. There are some detailed changes as follows:
1. Line 133-135: Separate supergene from hypogene (stages 1-3) in the presentation of the ore minerals.
2. Fix the name to Supergene in the table.
3. Line 515-523: Add Drummond and Ohmoto (1985) reference to explain the metal saturation implications of boiling.
4. Line 529-534: Add Burnham (1985) on implications of boiling to explosive brecciation.
Thanks again for your guidance and valuable suggestions. If you have any queries, please don’t hesitate to contact me through Manuscript Tracking System.
Best regards.
Shunda Li
Author Response File: Author Response.pdf
Reviewer 3 Report
Thank you for taking into account most of my comments and suggestions.
However, two main geological features do not support your interpretation and description.
I need to get clear data to validate the authors’s assumptions.
In figure 1b, the reference to fig.2, shows that most of the deposit area is hosted by Palaeozoic sequences. This contradicts the geological map the authors propose in Fig.2.
Then concerning the Figure 13. I previously suggested the authors explained why veins are flat at depth and steeper close to the surface.
The authors’s answer was in the cover letter but not in the manuscript. It may be problematic although I could accept the authors argue for not mentioning it as it is not the topic of your manuscript.
However, authors explain that steep faults (they have add the faults on the new fig. 13) control the orebody shape in the shallow part of the deposit and that in deeper, the mineralisation emplaced in a contact zone between the granodiorite and the strata. What kind of strata? There is no strata in a granite. I can admit some UST or the existence of a foliation but no strata.
Thus, I’d like the authors add some assumptions on why vein are flat?
If strata exist maybe it means that Paleozoic rocks occur at depth.
I suggest the authors read the following papers as they deal with steep veins and flat veins emplaced in shear zones both emplaced in granitic setting. They may cite both papers if the proposed models, which belong to the intrusion related gold deposit (IRGD) type model, convince them.
Dressel, B.C., Chauvet, A., Trzaskos, B., Carlos Biondi, J., Bruguier, O., Monié, P., Villanova, S.N. and Newton, J.B., 2018. The passa três lode gold deposit (paraná state, brazil): an example of structurally-controlled mineralisation formed during magmatic-hydrothermal transition and hosted within granite. Ore Geology Reviews.
Tuduri, J., Chauvet, A., Barbanson, L., Labriki, M., Dubois, M., Trapy, P.-H., Lahfid, A., Poujol, M., Melleton, J., Badra, L., Ennaciri, A. and Maacha, L., 2018. Structural control, magmatic-hydrothermal evolution and formation of hornfels-hosted, intrusion-related gold deposits: Insight from the Thaghassa deposit in Eastern Anti-Atlas, Morocco. Ore Geology Reviews, 97: 171-198.
Because stockwerk is missing, I suggest the authors discute why they support the porphyry model instead of IRGD one.
Author Response
Dear reviewer,
Thank you very much for your comments on our manuscript. All comments are valuable and helpful for improving the quality of the paper. We have fully considered the comments and thoroughly revised the paper. There are some detailed changes as follows:
1. In figure 1b, the reference to fig.2 has been remarked.
Sorry, it’s my mistake. Most of the deposit area is hosted by Jurassic granitoids.
2. Line 529-537: We explain the forming conditions of three types of mineralization (breccia-hosted ore, ring/radial-fault-controlled veins and disseminated ore).
There is no strata in a granite. The flat orebodies (No. 18) mainly occurred within phyllic alteration zone adjacent to the granodiorite. These orebodies, delineated according to the gold grade (>3.0 g/t), are lenticular or layered and characterized by veinlets and stockworks. (Line 126-127).
The above characteristics all support the porphyry model. The flat orebodies (No. 18) are not within the UST or foliation of wall rock like IRGD.
Thanks again for your guidance and valuable suggestions. If you have any queries, please don’t hesitate to contact me through Manuscript Tracking System.
Best regards.
Shunda Li
Author Response File: Author Response.pdf
