Sea-levels and prehistory in Gwaii Haanas

Abstract

Integration of palynology and micropaleontology in an analysis of sediment cores and stratigraphic sections from the Gwaii Haanas Archipelago (southern Moresby Island) and adjacent Hecate Strait allows improved detailing of the sea-level curve for Haida Gwaii (Queen Charlotte Islands). Transgressive and regressive events are established through analysis of several types of microfossils inluding pollen, dinocysts, diatoms, foraminifera and thecamoebians. This research shows that the early Holocene marine transgression in this area was very rapid. Mean sea level reached a maximum elevation of approximately 14 metres above present levels at about 9,000 years ago and relative sea-levels remained between 12.5 and 14 metres elevation above present levels until about 5,500 years ago. These results are highly significant in the search for and meaning of early archaeological sites in this area.