F-zone
Tags: arsenopyrite basalt bif biotite calcite chert chlorite dyke gabbro greenstone belt grunerite hornblende pyrrhotite
The Meliadine gold project (including the Wesmeq deposit) is located in the Kivalliq District of Nunavut in northern Canada, approximately 25 km northwest of Rankin Inlet on the west coast of Hudson Bay. A private all-weather access road constructed by Agnico Eagle connects Rankin Inlet to the Meliadine project. The current Meliadine exploration camp is located on the shore of Meliadine Lake, approximately 2.3 km east of the Tiriganiaq deposit.
Regional geology: Rankin Inlet Greenstone Belt
Located in the Northwest Hearne Sub-domain of the Churchill Structural Province that forms part of the northern Canadian Shield. Supracrustal rocks of this belt consist of mafic volcanic rocks, felsic pyroclastic rocks, sedimentary rocks and gabbro sills of about 2.7 billion years old that have been polydeformed and metamorphosed (Bannatyne, 1958; Laporte, 1983; Tella et al., 1986; Tella, 1994).These rocks were deformed in both the Archean and Proterozoic eras.
Meliadine area regional geology:
Deposit geology:
The stratigraphic sequence in the F zone deposit area strikes northwest-southeast and dips from 45º to 50º to the north.
The host rocks for F zone are chlorite-rich massive to pillowed basalts of the Wesmeg Formation, which are cut by rare gabbro dykes and interflow sediments. Within the Wesmeg Formation are chert-rich and iron-poor rocks of the Lower Lean Iron Formation that consist of metre-scale cherty iron formation units interbedded with centimetre-scale volcanic units. The iron formations that host the gold mineralization vary in thickness from metres to tens of metres. This great thickness is interpreted to be the result of the intersection of an east-southeast-trending iron formation with a dominant east-west-trending structure and a second southeast-trending structure. Plunges of these thick mineralized iron formations vary from steeply northeast to steeply northwest.
F zone vertical cross section at 17,425 E (local grid) showing geology and lode wireframes:
Mineralization:
Mineralization in the F zone gold deposit is strongly associated with shearing and quartz veining within the Lower Lean Iron Formation. Thicker sections with higher gold grades are controlled by the intersection of the east-southeast-trending iron formation with a dominant east-west-oriented structure and a second southeast-trending structure. Plunges of this thickening vary from steeply northeast to steeply northwest depending on local changes in strike.
Free gold occurs as discrete blebs in pyrrhotite and quartz shears and to a lesser extent along fractures and grain boundaries in large recrystallized arsenopyrite.
Alteration envelopes occur adjacent to quartz-calcite veining and are characterized by hornblende/grunerite-, biotite- and calcite-bearing assemblages that overprint the pre-existing regional greenschist metamorphic facies.
Note:
History, local geology, deposit geology, and deposit type are described under the Tiriganiaq deposit.
For mineral resources and reserves (as at December 31, 2010):
- Indicated resources cut-off grades: 1.83 g/t (in pit) and 2.79 g/t (out pit). The table presents combined open-pit and underground resources. Contained gold (metric tonnes) was calculated by goldmap.info.
- Inferred resources cut-off grades: 3.78 g/t. Contained gold (metric tonnes) was calculated by goldmap.info.
For mineral resources and reserves (as at December 31, 2014):
- The mineral reserves are inclusive of the mineral resources
- The table presents combined open-pit and underground resources (calculated by goldmap.info)
- The gold cut-off grade for open pit mining is 2.42 g/t
- The gold cut-off for underground reserves is 4.15 g/t
- Contained gold (metric tonnes) was calculated by goldmap.info.
Mineral Resources (Dec. 31, 2010)
| Class | Ore (ktonnes) | Au grade (g/t) | Au (kg) | Au (oz * 1000) |
|---|---|---|---|---|
| Indicated | 1894.00 | 5.39 | 10201.15 | 329.00 |
| Inferred | 1010.00 | 5.62 | 5676.20 | 183.00 |
Mineral Resources (Dec. 31, 2014)
| Class | Ore (ktonnes) | Au grade (g/t) | Au (kg) | Au (oz * 1000) |
|---|---|---|---|---|
| Indicated | 2529.00 | 4.81 | 12171.84 | 392.00 |
| Inferred | 1473.00 | 6.80 | 10020.10 | 322.00 |
Source:
-
Updated Technical Report on the Meliadine Gold Project, Nunavut, Canada
(12.03.2015, Toronto)
Authors: Connell Larry, Petrucci François, Larouche Julie, Caron Denis, Laflamme Dany, Robichaud François, Proulx Alexandre -
Technical Report on the December 31, 2010, Mineral Resource and Mineral Reserve Estimate,
Meliadine Gold Project
(16.02.2011, Nunavut)
Authors: Duquette Dyane, Matte Pierre, Caron Bertho, Connell Larry, Fournier Julie, Petrucci François