Shallow sediment temperature perturbations and sediment thermal conductivities, Canadian Beaufort Shelf

• Published in: Canadian Journal of Earth Sciences
• Main Authors: Taylor, Alan E., Allen, Vic
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1987
• Subjects: General Earth and Planetary Sciences; Beaufort Shelf; Beaufort Sea; permafrost
• Online Access: http://dx.doi.org/10.1139/e87-210; http://www.nrcresearchpress.com/doi/pdf/10.1139/e87-210

A regional survey of sediment temperatures and thermal conductivities was conducted at 33 stations across the outer shelf of the Canadian Beaufort Sea. Techniques developed for deep-ocean heat-flow investigations were used to study the upper 3 m of sediments. Temperature–depth profiles exhibit curvatures that may be explained by seasonal changes in bottom-water temperature; some curvatures may arise from other causes. It is unlikely that thermal effects of the underlying, degradational permafrost can be detected from such shallow temperatures because of the magnitude of, and lack of independent knowledge of, these transient and local influences. Thermal conductivities measured on sediment cores and corrected to −1 °C range from 0.9 to 2.4 W m −1 K −1 (average 1.26 ± 0.2 W m −1 K −1 ). These values are higher than typical conductivities of deep-ocean sediments. The wide range of thermal conductivities observed across the outer Beaufort Shelf may be explained by the presence of a varying fraction of quartz sand that represents a component of high conductivity.