Timmins TwpThe RT Minerals Timmins Township property lies within the northwest-southeast striking Lake Timiskaming Rift Valley (LTRV), approximately 50 km southeast of Timmins, Ontario. This major structure is the site of several mining camps in northeastern Ontario, including the Cobalt silver camp, the Kirkland Lake gold camp and the Timmins gold/base metal camp, including the Kidd Creek Mine (
OGS Miscellaneous Paper 39).
In the geological past, the majority of VMS deposits were formed in
rift environments associated with volcanic rocks. Alteration haloes developed by VMS deposits are typically
conical in shape. More on that later.
Within the LTRV, there are 3 major NW/SE striking faults, including the Quinze Dam Fault, the Cross Lake Fault and the Montreal River Fault. All 3 of them have played a major role in the forming of either gold or base metal deposits.
With respect to RTM's Timmins Property, it is located just to the west of the Cross Lake Fault, about 2 km away (
Map P.3421). To the north of the property, in Sheraton Township, is where the Cross Lake Minerals VMS discovery is located. The discovery sits in the northwestern corner of the township, southwest of Sheraton Lake, with the major Cross Lake Fault traversing through the middle of the deposit (
Map P. 3387).
Of importance to RT Minerals however, is that there is a splay fault coming off the Cross Lake Fault. Beginning near the north central boundary of Timmins Township (
Map 2543), there is a north-south fault heading south towards the Timmins Twp Property, and passes by just to the east of Dougherty Lake, particularly coinciding with the north-south Gibson Lake Road. This fault continues on south and passes just to the west of the Matachewan gold camp, and then continues further south until it passes through the middle of the Gowganda silver camp.
I'd say that this major north-south fault zone is a very fertile fault zone!! The following are a few comments by Ann Wilson, former Resident Geologist for the Ontario Geological Survey, Timmins Office, describing some of the features of the Cross Lake VMS Deposit, taken from (MDI42A07NW00013).
"The predominant lithologies are felsic to intermediate volcaniclastic rocks consisting of ash tuff, lapilli tuff, crystal tuff and agglomerate with lesser volumes of massive or brecciated rhyolite and mafic tuffs. Thin, silica-rich finely laminated white units, possibly of exhalative origin, occur in proximity to the base metal-mineralized zones. Intrusive rock types consist of quartz feldspar, feldspar porphyry and diabase. The felsic volcanic sequence dips steeply southeast and faces southeast. The lowest unit intersected in the zone is the Tiger Stripe, which is a sheared porphyry or crystal tuff which displays regular, thin banding caused by layers of sericite.
The deposit consists of a steeply dipping, eastern zinc zone with an overlying copper zone located down plunge to the west. Zinc grades are mainly in the range of 1% to 6%, but local high grade pods contain 18% Zn over a true width of 3 m, with silver values ranging up to 911 g/t Ag. Copper grades of 1% to 3% have been encountered over estimated true widths of up to 12 m including higher grade sections. The Cross Lake zone has generally higher concentrations of zinc relative to copper".