Delayed Bedrock Response Beneath Ice Sheets
qAs ice sheets grow, the pressure
of their weight on
the underlyingion bedrock becomes significant.
qDue to the different densities
of ice and rock, a
ice sheet of 3000m thickness is roughly equivalent to the weight of 1000m of solid rock.
qThe
initial sinking would be elastic and immediate.
qThe bedrock later respond more
slowly and sinks
half of the remaining distance toward the eventual equilibrium every 3000 years.
qThe total
time to reach the final depression depth is about 15,000 years.
(from Earth’s Climate: Past and Future)