The present study uses a multi-criteria approach for a physico-chemical characterization of the ice in order to highlight its origin. A portable core-drill was used to obtain samples of relict glacier ice. Combined to the analysis of ice petrofabrics and cryofacies, high-resolution images of the internal structure of the ice cores were obtained using a computed tomography (CT) scanner. Geochemical properties (stable isotopes, ions, gas) of the ice were studied using common techniques such as mass spectrometry and ion chromatography. The age of the ice will be determined by paleomagnetism dating of fine sediments sampled from surficial deposits (in collaboration with Guillaume St-Onge, UQAR) and its relative stratigraphic position above a fossil forest sequence. Based on the analysis of the sediment particle size, the stratigraphic context of the study site will allow determining the past sedimentary depositional environment that resulted in the burial of glacier ice. As for estimating past climates of Bylot Island, temperature at time of ice formation will be inferred by the stable isotopic composition (δ18O) of the air trapped in the ice.