EVOLUTION OF THE THERMAL ENVIRONMENT OF SEDIMENTATION IN THE CASE OF A VARIABLE HEAT FLOW

Abstract

An important factor both in geodynamic modeling of the development of sedimentary basins and in investigating their oil and gas potentials is the analysis of their thermal environment as a function of time. There have been numerous studied of this subject, largely falling into two categories. The first investigates the cooling of anomalously hot material instantaneously uplifted to a known depth in the lithosphere, based on the assumption that cooling restores the original temperature distribution in that lithosphere. In the second approach the temperature and heat flows are calculated for a half-space with a steady-state temperature distribution that is disturbed by the movement of the upper boundary. No solutions have been obtained for problems of the thermal environment of sediment accumulation that would not only correct for the breakdown of a steady-state temperature distribution because of accretion of material at the upper boundary but also for a variable heat input at the lower boundary. In this paper the author uses an expansion technique on different scales to simplify the analysis of the evolution of the thermal environment of sedimentation in case of variable heat flow.