Skip to Main Content

Abstract

The stratigraphy of the Central Mine Sequence is remarkably well preserved and we 11 exposed. A 1 though disrupted by numerous northeast and northwest striking faults, the volcanic rocks have suffered little of the penetrative deformation typically associated with greenschist-facies regional metamorphism elsewhere in the region. The volcanic stratigraphy in the tour area comprises subaqueous andes it i c and rhyo 1 it i c flows with 1 ess than 5 % pyroclastic and epiclastic rocks. In a “younging” direction, and from west to east, formations include: The Flavrian Andesite, the Northwest Rhyolite, the Rusty Ridge Andesite, the Amulet Rhyolite, the Millenbach-Waite Andesite, the Millenbach QFP RhyoliteWaite Rhyolite, the Amulet Andesite, the Newbec Rhyolite and the Newbec Andesite (Fig. 5). Formations strike north-northeast, are gently folded about east-west trending and plunging axes, and dip from 5 to 55° to the east {Fig. 4).

The stratigraphy of the Central Mine Sequence is thought to represent the infilling of a primary volcano-tectonic depression or caldera (Dimroth et al., 1982; Gibson, 1989). Hydrothermal vents are coincident with volcanic vents and both show a strong spatial association to major synvolcanic faults which were active at various stages during successive collapse of the Noranda Caldera.

Volcanogenic Massive Sulphide {VMS) deposits, although clustered above the Amulet Rhyolite formation (Fig. 5), are scattered throughout 2 000 (+) m of stratigraphy and within individual deposits massive sulphide lenses may be stacked over vertical distances approaching 300m {Amulet Upper and Lower A, Fig. 8).

VMS deposits are of the

You do not currently have access to this chapter.

Figures & Tables

Contents

GeoRef

References

Related

Citing Books via

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal