These stratigraphic concepts form the basis for the Martian geologic timescale. This event marks the beginning of Nectarian period of the lunar geologic timescale. The Phanerozoic Eon is the current eon in the geologic timescale. Homogeneous nucleation is assumed to be negligible on the timescale of this experiment. The Santonian is an age in the geologic timescale or a chronostratigraphic stage. The expansion occurred on a much shorter timescale. The Gelasian was introduced in the geologic timescale in 1998. It would be irreversible on a timescale between decades and millennia. Generally a shorter half-life leads to a higher time resolution at the expense of timescale. GWP is measured relative to the same mass of and evaluated for a specific timescale. The timescale of the study also varies from days to centuries. Generally such predictions are overly optimistic in timescale. The formation timescale of giant planets is also an important problem. The archaeological evidence agrees with this earlier timescale. In practice, however, simultaneous determination of the timescale and heat capacity is difficult.