Jeremy Tonelli

B. Sc. Honours Thesis

The Joggins and Springhill Mines Formation, Interpretation and a Model for the Paleo- environment

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The Joggins Formation is located along the eastern shore of Chignecto Bay, Nova Scotia. The purpose of this investigation is to compile a bed-by-bed measurement of the Carboniferous strata within a 200m stratigraphic study area, then to classify the lithological units into facies types and finally, to model the depositional paleo- environment. Facies types observed within the study area include large, moderate, and minor sandstone channel-fill facies; undulating, thin sheet and tabular planar sandstone facies; grey friable, grey platy, red friable and red platy mudstone facies; a coarsening- upwards bay-fill facies; and a limestone, shale and coal organic facies.

A prominent feature of the lithology found in the stratigraphic section, is its cyclical and repetitive occurrence. Cyclicity can be observed as small-scale coarsening- upward or fining-upward packages (<10m) and as larger-scale grey and red assemblages (<40m). Smaller-scale cycles are divided by sharp erosional boundary layers, designated as flooding surfaces, while larger-scale cycles generally have gradational boundaries. Grey assemblages can be considered as reflecting wetland environments, whereas, red assemblages reflect arid environments.

Both these trends can be used to synthesize facies types by association. Successive environments, resulting as a response to variations in base-level, can be classified as either belonging to a progradational or retrogradational parasequence set. This establishes a contemporaneous link between facies types, and allows for the modelling of the paleo-environmental cyclical trends.

Keywords: Carboniferous, progradational parasequence sets, retrogradational parasequence sets, base-level, and facies types, sequences, and associations
Pages: 116
Supervisor: Martin Gibling