Abstract

One goal of the archaeological research at Lake Temagami is to discover the full sequence of prehistoric occupation since deglaciation (ca. 10,500 B.P.). Surveys and site excavations to date have focused on the modern shoreline. Lake and river shores formed an important ecotone for hurnan occupation in the Upland Shield - Boreal Forest as seen from ethnographic and archaeological settlement pattern studies. In order to trace prehistoric occupations through time, it is necessary to, reconstruct past shoreline configurations. Recent work indicates that lake levels in the complex north-south basin of Lake Temagami have been dynamic. Differential isostatic rebound is posited as the mechanism, with the northern end of the lake rebounding faster than the southern end. This phase of the research focuses on reconstructing the palaeohyhydrology of Lake Temagami, as a means of predicting archaeological site location. The effects of isostatic rebound were computer modelled by digitizing MNR 1:20,000 basemaps and applying published rebound curves. Initial results predict a 30m vertical displacement of the north end of the lake, relative to the south, at 9,500 B.P. Two separate lakes, one draining northeast through Sharp Rock Inlet, and the other draining northeast through the town of Temagami, would result. As the basins rebounded, lake regression would occur near these outlets, resulting in palaeoshorelines inland from the modern shoreline. Fieldwork in 1991 involved coring bogs at the two outlets. The preliminary results bear out several predictions of the computer model. This work has several archaeological implications. First, Lake Temagami levels underwent rapid change. Sites on the present shoreline may not provide the full sequence of prehistoric occupation. Second, changing lake levels differentially affected the basin; while inland archaeological survey may be useful for locating early sites, it is only appropriate in selected locales. Third, local effects of changing lake levels on travel routes, lithic sources, and fauna resources merit consideration in reconstructions of pre-historic land usage. Finally, this work has implications for heritage planning.