The transient and steady-state influence of sediment compaction and interstitial water expulsion on the temperature distribution in oceanic sediments

The transient and steady-state solution of the linear heat transfer equation considering the rate of compaction of sediments and the vertical migration of interstitial water are obtained, respectively, for a single layer and a multi-layer model of unconsolidated sediments. At steady state the temperature profile with depth becomes a convex curve rather than a straight line due to the presence of above factors. The time needed to reach the steady state is observed to be directly proportional to the square of the thickness of the layer. The thermal gradient at the surface increases parabolically with the increase in the rate of the above-mentioned factors.The application of the steady-state results to the bore hole in Amchitka Island (Sass and Munroe, 1970) suggests that the observed surface heat flow value differs by 14% from the calculated one. Also the heat flow value at greater depth is calculated to be 2.02 · 10⁶ cal cm ²s¹, which is close to the mean value for Phillippine Trench (Nagasaka et al., 1970).