Agnico Eagle Mines Ltd owns 100% of the Holt Complex, which includes three mines, the Taylor mine, Holt mine and Holloway mine, as well as the Holt mill.
Summary:
Regional Geology
The Taylor Mine Complex is located along the Porcupine-Destor Fault Zone (PDF), a major structural feature associated with globally significant gold deposits lying within the Abitibi Greenstone Belt of northeastern Ontario and north-western Quebec.
Local and Property Geology
The Taylor Mine Complex is almost entirely covered by glacial overburden, ranging from 3 m to 60 m in thickness (generally 30 m to 40 m thick). Thus, interpretations of the property geology have been made principally from diamond drill hole information as well as the underground excavations in the shaft and ramp areas developed in the Shaft Deposit.
The Taylor Mine Complex is located along the PDF in its central portion, approximately 60 km east of the main gold producers in the vicinity of Timmins. The PDF in the area of the Taylor Mine Complex strikes roughly east-west, and dips to the south between 40° and 60°, with the majority of the property lying to the south of the projected trace of the PDF. The PDF is a complex structural zone and it is more accurately described as a zone of tens of metres width, along which are contained many individual zones of movement. In the Taylor property area, the footwall of the PDF is considered to be a thick series of relatively undeformed and unaltered metasedimentary rocks intersected to the footwall.
Mineralization
The Taylor Mineralization is in close proximity, within the hanging wall, to the PDF. Over a strike length of 2.3 kilometres there are three mineralization zones that have been identified. From east to west these are:
- The Shaft Deposit, with gold mineralization associated with felsic intrusive rocks.
- The West Porphyry Deposit (WPZ), a system of stacked lenses, with the gold mineralization associated with felsic intrusive and altered mafic-ultramafic rocks (Green Quartz Carbonate).
- The Shoot Deposit, with gold mineralization hosted by argillaceous metasedimentary rocks within a package of green quartz carbonate.
Gold commonly occurs as relatively coarse-sized free gold in quartz, but also occurs as fine particles, which may be intimately associated with sulphides (particularly pyrite and locally, arsenopyrite) both in quartz-carbonate veins or in surrounding altered host rocks.
DEPOSIT TYPE
The deposit types vary within the Taylor Mine Complex. The Shaft Deposit furthest east is identified as a Felsic intrusive related model, with a contemporaneous green carbonate association. Feldspar porphyritic intrusions are the host to high grade gold veins and high concentrations of disseminated sulphides (generally pyrite).
Within the West Porphyry Deposit, free gold is found within quartz dominant extension veins and veinlets, cross-cutting the foliation present within the chrome-mica and chloritic altered ultramafic rock. This unit can be up to 20 m thick as the true extent of the veins are not fully understood. Additionally, the main shear (interpreted to be the contact of the PDF between the mafic and sediment contact, is host to a quartz brecciated shear vein, which can be up to 2m thick. Altered mafic units consisting of high concentrations of disseminated sulphides are also host to gold mineralization.
Similar to the West Porphyry Deposit, gold mineralization in the Shoot Deposit is associated with the quartz carbonate veins within argillaceous sediments bounded by green carbonate.