This is a proposal to perform a laboratory study of hydrothermal convection in the oceanic crust. Two separate experiments are proposed. Experiment (1) is a follow up on an experiment undertaken with NSF support in which a large tank, filled with glass beads to simulate a porous medium, was maintained at a differential temperature and a convection pattern was allowed to develop. In the proposed experiment (1) the experimental set up is essentially the same except that the upper boundary is modified so that part of it allows a greater fraction of the thermally convected heat to escape. This experimental set up is to simulate the effects of a highly permeable rock outcrop surrounded by a thick blanket of impermeable sediment on the pattern of convective heat transfer through the ocean floor. In experiment (2) a new apparatus is developed that will enable the visualization of high Rayleigh number convection in a fractured/porous medium. These types of studies are important to the understanding of heat transfer through the seafloor. The program considers experiment (2) to be of greater priority than (1) and that has been communicated to the PI.
