PS: This post, as is common for me, became a tome. Main segments:
- Reply to Arsenic
- Broad comparisons of late 2018 paper on Succouth and current announcement
- Trips down memory lane Sudbury Cu rich veins and Creighton;
- Thompson, Manitoba stratigraphy and possible research implications for the WMP.
Hi Arsenic,
You are right this announcement has triggered thoughts and memories. I did miss your post about vms/magmatic and repeated that comment.
Regarding your questions
1) are the structures much more complex than you perceived previously.I hadn't really thought too much about the structure before this question.
This plan view of the resource is based on wide spaced drilling and to realise the full 156Mt at the 0.3% cutoff level (
2015 maiden resource Succouth Ann,) meant that the many scattered blocks needed to be mineable.
For all these blocks to be mineable there needs to be some continuity but the distributions/patterns don't lend themselves to easy analysis.
Thinking about it as this post happens some (probably not all) of these more isolated ?shallow blocks could come within an open pit shell required for economic and geo tech. stability etc. Also infill drilling may have shown continuity especially in the core area.
From the original 2015 Ann. this was one of the sections given.
As an exercise at University we were given "simplified" sections with only the intersections shown and asked to join the "dots". There was not necessarily a correct answer to the structures present for such theoretical problems. Multiple combinations of faults, folds, thrusts etc mean that such intersections can be connected in many permutations. However, add in more data and some of these possibilities become unviable.
At Succouth the dots/intersections have been put into structures that match the current detailed data. If these data are accurate the model should be too.
From the current announcement comes this re-interpretation to which I have added potential drill holes and results if the model is accurate. Holes missing fold noses above and below. The bulk grades, to date, do not suggest any strong Cu (?Ni) concentrations in fold closures. Rather, narrow high grades on the dyke margins to taxite and as xenoliths (rafts) in the dolerite.
When there is a model presented it does become difficult to think of alternatives but to the geologists (+academics +??) who have done the work there may be some clues which niggle (or shout) in the back of their minds that something else is going on and a new model begins to evolve.
- see below***.
2) is what will eventually make resource fro Succouth more likely to be larger than you though pre- the announcement.No direct answer It may be swings and roundabouts with this in that some areas could lose while others gain for little change. With a folding model some of the depth extent may be lost but plunging fold noses may compensate.
The annotated section above gives some idea of what this may mean. Further implications for mining possibilities are for how deep an open pit would be feasible. If the above section is correct then 500m would be required, which is a possibility if economics permit. How any folds plunge also becomes important - sub horizontal vs inclined.
Having said this for local Succouth the main mineralised unit (Taxite) appears to be very widespread and open in many directions including 4 Kms to the west at Babylon, to the south at Esaglia and poorly explored under a palaeochannel to the east and probably to the east at Suez.
Leads to speculation of regional potential that is common in exploration geology and means more geophysics, drilling, studies etc.
IMO sort out Succouth first with perhaps a few wildcat holes if good targets are forthcoming.
[Deep drilling at Babylon (late 2016? with EIS funding help) was disappointing and failed to indicate significant increase of Ni at depth. (Couldn't find reference so memory only)] The Cu grades in Taxite at Babylon and Esaglia are similar to Succouth.
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See Below***I found this late 2018 paper on Succouth while doing some research for this post. I have bought it, but copyright issues limit what I can pass on. I have sent the company an email requesting they post it on their website...a long shot.
The images are available by googling SUCCOUTH WEST MUSGRAVE2018. and many other ways.
Using the above link and google images and scrolling the image in the bottom LH corner gives thumbnails of figures in the paper.
The text in Monday's announcement summarises some aspects of the new model presented in the paper. The paper provides the highly technical background to this and gives some idea of the detail research that has been going on at Succouth and presumably for the overall WMP.
To have a paper published is a lengthy process and requires peer review among many other checks before it appears. The research to get this paper out has probably been going on for a long time and near the form it came out in by late 2017. More drilling will refine the model.
IMO the 3 drill holes reported were tests of the model and confirm, at least, the basic concepts may be correct.
Some points in common between the paper and announcement (details omitted for obvious reasons - too technical etc and not appropriate):
- Folding - although the images appear to be mirror images [probably one viewed NE other SW].
- Evidence for folding is based on geochemistry (strong emphasis in paper), logging (contacts/symmetries of lithology/micro structures).
- Nebo Babel and Succouth have subtly different ages 1068 vs 1078My (from paper) which combined with geology and structural/metamorphic differences strongly indicate two different mineralising events (at least).
- Economic minerals present (from paper) include dominant disseminated chalcopyrite, plus minor Cu minerals in form of bornite, digenite, covellite; plus minor Ni minerals in the form of pentlandite, millerite. PGE's may form a payable by product. Paper gives Cu:Ni ratio of 10:1.
- Local high grade Cu +- Ni seems to occur in small rafts within dolerite dykes that post date mineralisation and locally on the brecciated margins of the taxite.
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The last point is a follow on from my
last post here about local high grade Cu or Ni which triggered memories of the Sudbury basin.
I searched for a photo I remember that was posted by a company that was taken over by ever bigger fish until it ended up in the belly of Polish major KGHM. Since the web site is gone, so has the picture which from memory showed a 1+-m wide vein of high grade chalcopyrite snaking across 5+m of a glacially polished
SURFACE outcrop.
This underground image and accompanying blurb show how FNX made some money from such veins that occur at depth. The bright brassy yellow vein is near pure chalcopyrite.
Doesn't hurt that this 20+-% Cu vein also contains 1-5 ounces of Platinum Palladium Gold (PGEs) etc
Blurb :FNX underground at Levack mine.
=
Some other Cu vein images from Sudbury (Wallbridge -Broken Hammer ?deposit/mine)- not certain if they are in a pit or surface.
The image on the left looks like a fracture fill with probable high grade Cu.
Right image shows how complex the chalcopyrite rich veining (?remobilization) can be - foliation parallel, folded, breccia fill? and perhaps fracture fill.
Succouth sounds like it may have been mostly disseminated chalcopyrite with minor bornite that was subsequently metamorphosed and ductilely folded to give some local concentrations which may resemble this plus Ni concentrations - pure wondering and speculation on my part.
Much better exposures must have been present back in the 1880s when Sudbury was first developed. Wow....what those guys must have seen.
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I visited the, then Inco, Creighton mine in the mid 70's and went down to the 6900 foot level where the massive sulphide deposit was 400 feet thick and graded some 7% combined Ni/Cu plus undisclosed PGEs. They, now Vale, are down to ?8200 feet! (2.5Kms) with exploration to 10000.
While impressive and the treasure chest this Ni Cu sulphide it was something the geos mentioned around the 5000 foot level that was amazing to me. Apparently there was some process that concentrated copper into the footwall of the deposit there and produced a "small" pod of 20% Cu low Ni and ounce PGEs - 5 million tons! from memory. Perhaps the 403 body in this image. Seem to be more footwall deposits at depth but seismicity is becoming a significant issue with depth.
This is "just" one of several deposits at Sudbury that have been/were mined for 50 to 100+ years and made me aware of what management must think about something like Wingellina (east of the WMP which was an Inco 1950's discovery) and what exploration targets would they like. Thompson in Manitoba gave them 50 years probably was shut down last year.
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Finally, from Thompson, where I worked in the early 70's,
the research geologists faced complex lithologies and structures which the started to understand by the late 1970s.
This 2004 paper shows (to me) the significant evolution of geological thinking over 25 years. Check out the pictures in the paper, if nothing else, as they show how complex the gneissic is at Thompson and what these researchers can now map even after such intense cooking up and squishing (read metamorphism and structure) has happened.
The WMP is at an earlier stage but lessons learned at Thompson and other high grade metamorphic environments around the world suggest a fair understanding of the geology can be reached in time. Whether there will be the time or money is another question altogether.....
Such research requires a lot of effort but can yield major economic rewards in the form of new discoveries when part of an integrated exploration program.
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Well done if you made it this far. Persistence is needed for most projects
GLTAH
