Sedimentologic Description of Part of Coal-Bearing Carboniferous Sequence Exposed Near Joggins, Nova Scotia: ABSTRACT

Abstract

A 300-m section of the upper Cumberland Group exposed south of M'Cairn's Brook near the village of Joggins, Nova Scotia, includes five lithologies, including sandstones, siltstones, claystones, carbonaceous shales, and coal. The sandstones and siltstones display one or End_Page 730------------------------------ more of the following sedimentary structures: trough cross-beds, ripple laminations, horizontal laminations, convoluted laminations, or massive bedding. Additional features present include vertical accretion deposits, lateral accretion deposits, and crevasse splay deposits. A statistical analysis of the several facies and the contacts between them resulted in interpretation of the environments of deposition as a meandering river and associated flood plain. The lower half of the section, including a significant number of coal beds and carbonaceous shales, was deposited primarily within the flood-plain basin, whereas the upper part of the section, with coarser grained siltstones and sandstones, implied deposition closer to the channels. In addition to the sedimentologic analysis, a petrographic study of the coal beds was conducted. Results of a maceral analysis indicate a probable freshwater origin for the coals. Identification of the plant fossils found over the coal beds reveals a freshwater flora, and the mode of preservation indicates deposition in a crevasse splay deposit. End_of_Article - Last_Page 731------------