After studying the stratigraphic record of the area it was found that there was a change in the abundance of foraminiferal species through time. This usually indicates a change in environment. The changes in the harbour can be attributed to the eustatic, isostatic and tectonic events affecting the area.

Before the Northwest end of the harbour was opened up due to subsidence of the ocean bottom and sea-level rise, the harbour had a shallow littoral restricted environment and a low salinity. As sea-level rose, the circulation in the harbour improved which resulted in a shallow littoral to subtidal environment with a hgher salinity.

The Foraminiferal species assemblages found throughout the stratigraphic section at Montague Harbour were all typical of a west coast shallow subtidal environment.

The stratigraphic section can be broken up into two sections with Biofacies 1 including all samples from the upper part of the section and Biofacies 2 including all samples from the base of the section. The relative abundances of C.excavatum(Terguem, 1876) were much higher in Biofacies 2 than in Biofacies 1. Since these forams have been known to inhabit areas of lower salinities, a lower relative salinity can be assumed for the base of the section. This hypothesis is further supported by B.tenerrima(Bandy,1950) which showed a distinctly opposite distribution. B.tenerrima is indicative of a higher salinity environment and was found with a hgher abundance in Biofacies 1.

A study by Patterson and Luternauer(1993) found that abundances of C.excavatum were inversely related to water salinity compared to B.frigida(Cushman, 1922) and E.hannai(Cushman and Grant,1927). The two latter species were found in higher abundances in Biofacies 1 which may indicate a higher salinity environment

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