Layers of high thermal conductivity in the North Atlantic

Quartz-sand layers in the NW Atlantic basin have thermal conductivity values more than twice as high (up to 4.5 mcal/cm sec °C) as the values for normal sediment. The layers are thick enough to affect the measured temperature gradients; thus many thermal-conductivity measurements must be made to obtain an accurate heat-flow measurement in this part of the Atlantic. The conductivity of the layers cannot be estimated accurately from the water content of the sediments by using the empirical curve determined by Ratcliffe.