The geological setting, petrology and facies analysis of the Nepisiguit Falls Formation, Bathurst mining camp: An example of a deep submarine pyroclastic eruptive sequence

Facies analysis of the Nepisiguit Falls Formation indicates that there are three principal lithofacies associations: (1) primary pyroclastic, (2) resedimented syn-eruptive, and (3) epiclastic and chemical sedimentary. The distribution of the these lithofacies association suggests that there are at least two major volcanic centres within the Brunswick Belt, which are located near Brunswick No. 6 and No. 12, i.e., coincident with major volcanic massive sulfide deposits.;Inherent to our understanding of the facies and basin analysis of the Nepisiguit Falls Formation is the plausibility of having explosive silicic volcanism at bathyal depths (i.e., at depths greater than 500 m). Results of the CONFLOW modeling support the hypothesis that magmatic volatile phase expansion is alone capable of providing enough energy and high enough gas/melt ratio to initiate submarine pyroclastic eruptions in silicic magmas to the water depths typically associated with the genesis of volcanogenic Cu-Pb-Zn massive sulfide deposits.