Red Lake - (some) places to search for goldGullrock:
``Recent high resolution magnetic and electromagnetic surveys combined with a complete compilation of past exploration work allowed to identified untested geophysical anomalies on the property. Those untested anomalies match with soil sampling gold anomalies and are located in the Mine Trend structures.`` ``
The Gullrock property bears similar geology as the Campbell-Red Lake Mine setting. Underlain by the Balmer Formation,
Seven kilometers of strike length of the “Mine Trend”,
Proximal to the Confederation-Balmer unconformity,
Presence of ultramafic rocks and Temiskaming-type sediments,
Presence of F2 generation folds.``
1) Balmer Assemblage
``The Balmer Assemblage hosts all the major producers of the Red Lake Belt.`` 2) Gold at Upper Levels (near surface)
I think Red Lake has a reputation now of having mainly deep ore bodies, due to Goldcorp`s deep high grade discovery. I think people forget that Campbell-Red Lake Mine was in production for something like 50 years prior to the high grade zone being discovered at depth. They started producing gold at the upper levels - way back then.
If Alexandria finds gold at Gullrock, some will likely be found at the upper levels, as well. The geophysical anomalies that have showed up in the magnetic surveys (at Gullrock) are likely located at the upper levels (nearer to the surface). In addition, the positive (for gold) soil samples were taken in the B-Horizon. That is subsoil, which is just a few metres below topsoil.
As such, I don`t think Alexandria has to start the drill testing (at Gullrock) with expensive deep drill holes. I think somewhat shallow (reasonable cost) drilling can test the anomalies.
As you can see from the 2 maps immediately below, the Campbell-Red Lake Mine once housed plenty of upper level mineralization (removed through 50 years of production). The High Grade Zone (HGZ) is located around 5,000 ft down (around 1,500m).
Link, if image doesn`t show up:
https://www.rupertresources.com/i/maps/section2.gif 
Link, if......:
https://content.edgar-online.com/edgar_conv_img/2011/03/31/0000950123-11-030947_O69435O6943529.GIF 2) Deep High Grade Zones (possible feeder zones)
Of course, we all know about Goldcorp`s high grade zone. It`s not clear if it is a feeder zone on the property, but it likely is.
Other properties at Red Lake with gold deposits at upper levels could have feeder zones at depth also, or feeder zones (supplying gold) from nearby locations within the district.
3) Unconformity Contact Zone
The Unconformity along Goldcorp`s Mine Trend is located between the Balmer Assemblage and the Confederation Assemblage rocks. It seems to be a good place to look for gold at Red Lake.
You can see examples on the map below, with the Mcveigh Tuff and the Austin Tuff, at the Madsen (Red Lake) Mine.
Image, if.....:
https://blog.ceo.ca/wp-content/uploads/2014/08/pgm-feeder-zone.jpg 4) Ultramafic Intrusive Contact
Sometimes, high grade gold zones are found along the contact area of the ultramafic intrusive rock, at Red Lake. A good example is also on the map above.
5) F2 Folds
It seems like some of the rocks can fold (sometimes) at Red Lake, including the F2 Folds and the Ultramafic rocks.
It seems like Goldcorp has had success with mineralization within their F2 Folds, for decades. And, maybe other mines have had success over the years also.
However, Rubicon has had issues recently, with their F2 Folds. It sounds like Rubicon`s problems might have been heavily influenced by management though. It sounds like their drilling were too widely spaced (100 metres apart). The folding nature of this structure requires more detailed drilling (and less projections) before bringing the F2 resource into advanced resource categories.
6) Other
I think there are other zones and structures also, including dikes, shear zone, faults, etc.