University of Colorado 1973 Field Season on Baffin Island

Abstract

A total of 10 persons, including members of faculty, graduate students and assistants were involved in the 1973 field season of the University of Colorado in both northern and southern Cumberland Peninsula. The major objectives of the research undertaken were: (a) to study the Quaternary geology and geomorphic processes operating within the Baffin Island National Park and on the Peninsula in general; and (b) to study the energy balance and break-up pattern of the Home Bay fast-ice sheet. ... During the 1973 field season this research was expanded to include significant portions of the southern part of Cumberland Peninsula and of traverses through the main north-south passes of Pangnirtung Pass and the Padle/Kingnait fiords trough. ... Field work was also carried out on the Tertiary basalts at Cape Dyer during which particular attention was paid to the weathering of the basalts and the vertical and horizontal extent of active ice during the Quaternary glaciations. The basalts were free from Precambrian erratic rocks from the west, and the maximum extent of glaciation appears to be marked by weathered lateral moraines below the lower DEW Line site. Marine shells were found associated with these tills and will be uranium series dated. Investigations in Pangnirtung Pass and the Kingnait/Padle trough to the east revealed thick deposits of "bedded sands". These deposits, which are probably colluviated loesses, are interbedded with thin organic partings and thicker units of peat. The deposits vary between 0.5 m. and 5 m. in thickness. Buried soils were found underlying late- and possibly mid-Wisconsin moraines in Pangnirtung Pass. These together with samples from the buried sands are in process of being radiocarbon dated. Studies in the diffluent valleys (cols at about 600 m. above sea level) leading from Pangnirtung Pass eastward towards the Padle/Kingnait trough suggested that early Wisconsin ice flowed eastward from the Pangnirtung Pass but that much of the area was ice-free by late Wisconsin time, and possibly well before that. Studies were made on the south coast of Cumberland Peninsula, and shorelines and moraines delimited. A traverse was made (from the southwestern margin of the Penny Ice Cap south along the Ranger River to Clearwater Fiord. Pronounced weathering breaks occur across specific moraines, and some of the moraines close to the Penny Ice Cap appear surprisingly old. ... The study of surface energy budgets of the fast-ice of Home Bay was continued in 1973 when measurements were taken over the period from early spring and through summer break-up and subsequent freeze-up in late autumn. Studies of the fast-ice morphology during the ablation period were carried out from field surveys and satellite imagery. Seasonal variations in temperature, and salinity of the near-surface waters in the vicinity of Broughton Island, were investigated in relation to ice and current conditions. It is expected that further measurements on the ice due to be taken during the 1974 summer season will complete the basis for a description of the annual fast-ice cycle. A program of meteorological observations was conducted at INSTAAR's Broughton Island base during the summer and autumn months of 1973. In addition to conventional measurements, a continuous record of global and net radiation was obtained which was supplemented by measurements relating to atmospheric transmissivity and the radiative characteristics of clouds. The accumulated results of four summer and two winter seasons radiation studies are being analysed as the basis for a radiation climatology of the eastern Baffin Island region. Studies of the synoptic climatology of the Baffin Island region are proceeding, with climatic data and energy budget parameters incorporated into the basic catalogue of synoptic types. ... The Boas Glacier (67°35' N, 65°16' W) was resurveyed for the fifth consecutive summer. The 1973 ablation season was one of net loss of 0.42 m. water in accordance wi th an apparent pattern of strong mass gains and losses in alternating years. There has been a net gain of 0.40 m. water since August 1969. Long-term monitoring of this glacier seems justified from its already established position as a benchmark glacier for the northeast side of the Cumberland Peninsula.