Stratigraphy Of Western Newfoundland

The St. George Group is an approximately 500-m-thick sequence of carbonate rock in western Newfoundland. This report defines and explains the stratigraphy of these Lower Ordovician rocks, including the regional geology and geography, their age, and a review of work already done in the area.

This report is a documentation of the stratigraphy, paleonotology and sedimentology of these deep water sedimentary rocks. It provides the firstdescription of this deformed yet surprisingly intact sequence deposit at thefoot of a continental slope. A new stratigraphic nomenclature has beenerected which reflects discernible proximal versus distal faciesrelaionships. Intercalation of deep water graptolite and trilobite faunaswith shallow water boulders containing trilobites and brachiopods permitscorrelattion between quite different faunal realms, which is of internationalsignificance for early paleozoic biostratigraphy. The sediments reflectchanges in the depositional regimen of the adjacent shallow platform marginwhich accreted in response to the evolving community of carbonate producingorganisms and eustatic fluctuations in sea level. The report includes anextensive appendix which details the stratigraphy and paleontology of allimportant stratigraphic sections.

This report details stratigraphic, structural, and metamorphic relationships within the Corner Brook map sheet (NTS 12A/13) and adjoining segments of the Little Grand Lake and Harrys River map sheets (12A/12 and 12B/9) within the western part of the Appalachian orogen in Newfoundland. The report provides a detailed description of the rock units, the first integrated structural and metamorphic analysis, and the first reliable radiometric data on the rock units and events within the study area. These data allow for the development of a new model for the timing and nature of interaction between the Humber and Dunnage zones and have implications for the timing of mineralization in the region.

This volume focuses on the Canadian Appalachian region. The chapter on the East Greenland Caledonides stands alone and there is no attempt to integrate the geological accounts of the two far removed regions. Rocks of the Canadian Appalachian region are described under four broad temporal divisions: lower Paleozoic and older, middle Paleozoic, upper Paleozoic, and Mesozoic. The rocks of these temporal divisions define geographic zones, belts, basins, and graben, respectively. The area is of special interest because so many modern concepts of mountain building are based on Appalachian rocks & structures.