| A thermodynamic analysis of the energy exchanges between Sea and Cryosphere allows to
demonstrate that time derivative of Oxygen isotopic composition of the Ocean Bottom Water,
as recorded by Phanerozoic deep sea sediments, equals the time derivative of the energy
received by whole Hydrosphere from the Sun. The model accounts also for major
variations in the continental ice oxygen isotopic composition as deduced from Cenozoic
subglacial hyaloclastites and hydrothermal mineralizations in Northern Victoria
Land.
If this signal, under various assumptions, is purged by the albedo effects, the “energy”
signal may be relate to the Earth-Sun distance since the energy intercepted by our planet is
proportional to the square of its radius and inversely proportional to the square root of its
mean distance from the Sun.
I derived a temporal series for the variation of the mean distance of the Earth from the
Sun during Phanerozoic, which is compared with the temporal distribution of mantle
Superplumes related to the occurrence of basaltic plateaux or continental break-up. Strikingly
most of the Superplumes may be related to periods in which the mean Earth-Sun distance is
at minimum values. It is suggested that in this periods, tidal effects of the Sun may reach peak
values on the Earth-Moon system whose centre of mass falls within the mantle. Integration of
the gravitational effects of the solar system on both Climate evolutio and Plate
Motion theory, may help to explain largely debated questions like the break up of
supercontinents and the mechanism the induce inversions in the Earth magnetic field. |