MODELING SEAFLOOR-SPREADING RATES THROUGH TIME

A steady-state model of crust production and destruction for the past 180 m.y. was proposed by B. Parsons and advocated by D. Rowley. Such a model has serious implications for models of secular variations in global sea level, global climate, seawater chemistry, etc. This paper presents an analysis of the steady state model and then offers alternative extensions of that model that allow for non–steady-state production of ocean crust with time. Results suggest that the observed linear decrease in area vs. age of ocean floor does not force a steady-state view of seafloor spreading.