Silurian

Silurian 440 Myr Sea levels rise, two large continents form, hothouse climate. Diversification of jawless fishes, first bony fishes invasion of land by vascular plants and arthropods... 

Cullers, R. L., Yeh, Long-Tsu, Chaudhuri, S. and Guidotti, C. V., Rare earth elements in Silurian peltic schists from N. W. Maine, Geochim. Cosmochim. Acta 38, 389-400 (1974). 

Silurian Mt. Wills Granite. Gold mineralisation is structurally-hosted and accompanied by the presence of pyrite, arsenopyrite, sphalerite, aurostibite, and a variety of sulfosalts (Crohn 1958). Gangue phases include quartz and ferroan dolomite. 

Closure of the Tetagouche-Exploits basin by northwest-directed subduction from the Late Ordovician to Silurian led to incorporation of the back-arc terrain into the Brunswick subduction complex, accompanied by polyphase deformation and dominantly greenschist facies metamorphism (van Staal etal. 2003). 

The BSC (part of the Dunnage tectonic Zone) formed in Late Ordovician to Early Silurian (i.e., during the Salinic Orogeny), and contains the accreted and subducted remnants of the Middle to Late Ordovician Tetagouche-Exploits back-arc basin. Consequently, the rocks of the BSC have... 

VAN Staal, C.R. 1994. Brunswick subduction complex in the Canadian Appalachians record of the Late Ordovician to Late Silurian collision between Laurentia and the Gander margin of Avalon. Tectonics, 13, 946-962. 

Stratigraphic and geochemical interpretation of the Early Silurian Woodstock ferromanganese deposits, New Brunswick, Canada... 

Bevier, M.L Whalen, J.B. 1990a. U-Pb geochronology of Silurian granites, Miramichi terrane, New Brunswick. In Radiogenic Age and Isotopic Studies Report 3. Geological Survey of Canada Paper, 89-2, 93-100. 

The geology of the area consists of rocks from three time periods (Fig. 1) Silurian (Kingsclear Group), Devonian (Harvey Group) and Carboniferous (Mabou... 

This Silurian Group (418-424 Ma) has two formations associated with the Harvey area, Burtts Corner Formation and Flume Ridge formation, both consisting... 

The study area is situated in the Tobique-Chaleurs Zone, (TCZ) which contains early to middle Silurian sedimentary and volcanic rocks (Chaleurs group) that are disconformably overlain by Lower Devonian volcanic and sedimentary rocks of the Dalhousie and Tobique groups (Wilson 2004) and is bounded by the Rocky Brook-Millstream Fault to the northeast and the Mackenzie Gulch Fault to the north (Fig.1). The McCormack Brook Fault (a splay of the Rocky Brook-Millstream Fault) lies to the north of the... 

McKerrow, W.S. 1998. The Cambrian-Silurian tectonic evolution of the northern Appalachians and British Caledonides history of a complex, west and southwest Pacific-type segment of lapetus. In Blundell, D.J. and Scott, A. C. (eds) Lyell The Past is the Key to the Present. Geological Society, London, Special Publications, 143, 199-242. 

Williams, S. H. O Brien, B. H. 1991. Silurian graptolites from the Bay of Exploits, north-central Newfoundland and their geological significance. Canadian Journal of Earth Sciences 28, 1534-1540. 

In the northern part of the TCZ, the Chaleurs Group comprises subaerially deposited. Late Silurian bimodal volcanic rocks that overlie early Silurian shallow marine fine- to coarse-grained clastic and carbonate sedimentary rocks. The Chaleurs Group is overlain disconformably by bimodal volcanic rocks and interlayered sandstones and siltstones of the Dalhousie Group. 

Of special geological interest is the isotopic analyses of coeval carbonate-phosphate pairs (Wenzel et al. 2000), which helps to distinguish primary marine signals from secondary alteration effects and sheds light on the causes for 5 0 variations of fossil ocean water. Wenzel et al. (2000) compared Silurian cal-citic brachiopods with phosphatic brachiopods and conodonts from identical stratigraphic horizons. They showed that primary marine oxygen isotope compositions are better preserved in conodonts than in brachiopod shell apatite and suggested that conodonts record paleotemperature and ratios of Silurian sea water. 

SCHOEN (R.), 1964. Clay minerals of the Silurian Clinton ironstones,... 

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