Abstract
The Fridtjovbreen glacier surged for 12 yr (1991–2002). The maximum extent with a run-out distance of ∼4 km was reached after 7 yr. On the basis of ice-front behavior, the active phase of the surge can be divided into four stages: increased ice flow but stable ice-front position (30 months), advancing ice front (54 months with an average advance rate of 2.5 m day−1), maximum extent (12 months), and retreating ice front with persistent ice flow (∼36 months). The most prominent landforms developed during this surge are a network of composite thrust moraines on the deglaciated seafloor, with a sediment architecture indicating that ice flux persisted during the glacial retreat. Drawdown of land-based ice contributed to the protracted deceleration phase, and the intense thrusting was a result of ice flow along an undulating seafloor and the buttressing effect of a seasonally frozen fjord.
