Relative Sea Level Chronology Determined from Raised Marine Sediments and Coastal Isolation Basins, Northeastern Ellesmere Island, Arctic Canada

Abstract

A new relative sea level curve for the Robeson Channel area contrasts with previously published curves for the area by inferring that rapid emergence may have commenced at ca. 7400 BP, as much as 1200 yr earlier than previously predicted. Subsequently, uplift may have occurred at much lower rates from ca. 6000 BP to present. A comparison of shell dates used for the relative sea level curve and dates on disseminated total organic carbon (TOC) fractiop from lacustrine and marine sediments from sediment cores from emerged coastal lakes shows wide discrepancies. Furthermore, several inifmite TOC dates (>27,7SO to >40,600 BP) from glaciomarine sediments may imply that the region was ice-free during the last glacial maximum, but the validity of the TOC dates from the sediment cores is questionable due to variable contamination with redeposited detrital organic matter.

Holocene emergence and shoreline delevelling, southern Eureka Sound, High Arctic Canada

“…Similar sea level curves were presented for northeastern and eastern Ellesmere Island which show either an interval of sea level arrest subsequent to marine limit formation (England, 1983), or slow (1-2 m/century) initial emergence (England, 1997; see also Retelle et al, 1989). These curves contrast markedly with others reported from elsewhere in the region (Blake, 1975(Blake, , 1992aHodgson et al, 1991;Lemmen et al, 1994;Bednarski, 1995;Dyke, 1998) which show most rapid initial emergence (4.5-7 m/century), and are thus similar to curves from areas of the Canadian Arctic which were formerly covered by the Laurentide Ice Sheet (Andrews, 1970;Dyke, 1984;Dyke et al, 1991).…”

Alkenones, alkenoates, and organic matter in coastal environments of NW Scotland: Assessment of potential application for sea level reconstruction

“…Coastal isolation basins are natural coastal rock depressions isolated from or connected to the sea by changes in relative sea level (RSL). The utility of isolation basins in investigations of RSL change is demonstrated by research in Scandinavia [ Eronen et al , 2001; Kjemperud , 1981; Svendsen and Mangerud , 1987], Greenland [ Bennike , 1995; Long et al , 1999], Canada [ Retelle et al , 1989], Russia [ Corner et al , 1999; Snyder et al , 1997] and Scotland [e.g., Shennan et al , 1993, 2000, 2005]. Isolation basins on the north and west coasts of Scotland yield the longest archives of RSL change in the world (>16 cal kyr to present [ Shennan et al , 2000, 2005]).…”

Isolation of Lacustrine Basins and Marine Regression in the Kuujjuaq Area, Northern Québec, as Inferred from Diatom Analysis

“…Radiometric dating of marine to lacustrine transitions, preserved in cores from coastal basins, has been frequently used for establishing chronologies of relative sea-level change and isostatic uplift (e.g. Kaland etal., 1984;Bjôrck and Digerfeldt, 1986;Retelle et al, 1989).…”