Lac Savignac
Location, Access, Description
The Lac Savignac Property is located in the James Bay lowlands of northern Quebec, approximately 95km to the north of Chibougamau, Quebec. The Property currently consists of 45 active mining claims totaling 2,450.22 Ha in NTS 32J16. The claims are wholly owned by Globex and are not subject to any underlying royalties or third party interests.
Topography is quite flat and swampy in the eastern part of the property. Relief is more accentuated in the western part with NE-SW depressions and elevations comprised between 380m and 460m above sea level. The vegetation in the area is mostly composed of softwood (black spruce and jack pine). The southern portion of the property is clear because it was affected by a forest fire in 1997.
The project area can be accessed throughout the year along logging roads, which provide access to the property area. The property can easily be accessed during winter months with skidoos ; access might be a little bit of an issue in summer due to much of the property being underlain by swampy ground conditions dominated by sphagnum bogs and many small ponds.
Geology and Mineralization
Regional Geology
The Lac Savignac Property is located within the Superior Province of the Canadian Shield, in the sub-province of Opatica. The Opatica Subprovince is characterized by the abundance of tonalitic bedrock (undifferentiated gneiss and tonalites), enclosing green rocks metamorphosed to the greenschists to middle amphibolite facies during the Kenorean orogenesis. The basement rocks are cross cut with Proterozoic to more recent mafic to ultramafic dyke swarms orientated in 2 principal directions NW-SE and NE-SW, by which kimberlite magmas could have ascended.
Property Geology
The area of the property is almost entirely covered by non consolidated quaternary sediments. The dominant direction of glacial flow in this area is N220° à N230° (NE-SW). The main lithologies within the Lac Savignac area consists of intrusive felsic units of granodiorites-tonalites with localized fractures and injections of aplitic and pegmatitic dykes (DP-073, RG-189, MB-95-31). The area to the west of Lac Savignac is marked by the presence of Archean volcano-sedimentary sequences of the eastern portion of the Frotet-Evans Greenstone Belt. A lamprophyre dyke is mentioned 3 km southwest of the property (DP-073).
Kimberlites
The project area is located within the Temiskaming-Desmaraisville-Otish/Renard kimberlite corridor. Diamonds use to form at a very important depth within the Earth mantle and can be brought to surface within kimberlites pipes. Kimberlites are K-enriched ultramafic rocks forming in pipes rooted at great depth within the Earth’s mantle that commonly present either a circular magnetic high or low anomaly. Kimberlites contain phenocrysts of olivine which frequently serpentinized, phlogopite converted into chlorite, geikelite (“Mg ilmenite”), and chromian pyrope-enriched garnets that are encompassed in a fine-grained matrix of calcite, olivine, and phlogopite. Accessory minerals are ilmenite, magnetite, spinel, monticellite, apatite and perovskite.
The best way to find a kimberlite is to trace some kimberlite indicator minerals (KIMs) in regional scale basal till sampling, then try to identify the source as KIMs can travel up to great distances with glacial direction. The presence of certain KIMs such as pyrope garnets, kosmochloric diopside or picro-ilmenite is considered a good indicator of kimberlitic affinity. As not all kimberlites contain diamonds, research to facilitate mineral exploration has made it possible to discriminate between different types within KIMs, in order to determine whether the composition of a KIM reflects characteristics specific to the diamond’s exclusive stability field. Thus, a harzburgitic pyrope of G10 type or an eclogitic garnet of G3 type will be considered as better indicators for the presence of diamond-bearing kimberlites than pyropes of G11 type.
History
The Lac Savignac Property was subjected to very minimal exploration work prior to its acquisition by Globex in 2016. Regional exploration in the area was focused primarily for base metal mineralization in of the Archean Evans-Frotet-Troilus Greenstone Belt, southwest of Lac Savignac. Regional airborne magnetic and electromagnetic geophysical surveys were also completed by the MRN (DV-93-11, DP 84-48) with a 200-meter line spacing.
The most significant work listed in the Lac Savignac Property area consists of till sampling programs carried out by prospectors in 2002-2003, that resulted in some positive Kimberlite Indicator Minerals (KIMs) in the southeast of the Lac Savignac property (GM60816, GM61745, GM61878). In particular, a G3 pyrope has been uncovered on the Lac Savignac Property as well as a G10 pyrope less than 10 km southeast of the property, both considered as reliable diamond-bearing KIMs. Based on a comparison with basal till sampling at Renard, the distance of transportation of the KIMs at Lac Savignac is estimated less than 25km (Mougin, 2016, Internal Report).
In 2017, Globex carried out airborne magnetic survey followed by limited diamond drilling (DDH). Hole SAV-10-01 was headed to test a circular magnetic low anomaly and intersected hornblendite / pyroxenite, gabbro and quartz-diorite (GM70293). Limited pyrite, magnetite and minor chalcopyrite were observed within the quartz-diorite.
A NI 43-101 technical report of the Lac Savignac Property has also been written by Globex in 2018 (Rocco and Bambic, 2018).
Resources and Potential
No resource estimation has ever been calculated on the Lac Savignac property. The Troilus mine, which had a cumulative production of 67,946,868 metric tonnes at 0.1% Cu and 1.065 g/t Au from 1997 to 2009, is located 28 km NNW of the property within the Evan-Frotet Archean Greenstone Belt.
Despite no source for the KIMs has been identified yet by Globex and previous owners, given the number and nature of KIMs observed in the Lake Savignac area the probability of discovering kimberlites in the area NE of the property (opposite way of glacial flow direction) is quite good. KIMs typical of the diamond’s exclusive stability field have been uncovered in the Lac Savignac area confirming a fertile context for diamond exploration. By comparison with the Renard Mine, 41% of the samples collected from the Renard 1556 PEM in 2001 contained at least 1 KIM, 22% of the 2002 samples, and only 15% in the 2004 campaign. At Lac Savignac, 42% of the samples collected in 2002-2003 contained at least 1 MIK.
A series of circular magnetic anomalies can be interpreted on the magnetic data. In particular, a series of highly magnetic anomalies within a larger low magnetic anomaly is observed on the Quebec Vertical Gradient less than 5km NE of the property and could correspond to a kimberlites field. Further regional scale exploration should therefore be carried out. The NI 43-101 authors recommended detailed magnetic survey followed by focused HLEM (Horizontal Loop ElectroMagnetic) and Gravity and additional till sampling, before planning further DDH.