Glaciation and relative sea-level change in Maritime Canada

Relative sea levels in Maritime Canada have fluctuated between 70 m above and 100 m below present since the last interglacial period. Patterns of relative sea-level change are controlled both by the rates of ice retreat and the distribution of ice loads. Late-melting ice caps produced two types of anomalous sea-level response: (1) unmanifested emergence with low or no highstands in areas of thick ice, and (2) diachronous lowstand shorelines separated by regions not recording transgression. Deglaciation history must be considered when evaluating the Earth's response to former ice loads from the relative sea-level curves. In Maritime Canada, a high-amplitude, high-frequency relative sea-level response directly after deglaciation cannot be attributed to forebulge migration using current models of mantle viscosity due to the rapidity of relative sea-level fall. The apparent discrepancy between model and field data may be explained by initial direct isostatic recovery from thick Appalachian ice caps and late-melting ice caps. The migration of a peripheral forebulge appears to be recorded by regional uplift after 11 ka, resulting in slowing of relative sea-level rise and reversal points. The last interglacial marine deposits to 30 m above mean sea level suggest the possibility of long-term crustal subsidence and sea-level rise after glaciations.