Simulation of Particle Paths and Deformation of Ice Structures Along a Flow-Line on Storglaciären, Sweden

ABSTRACT

Paths, travel times and deformation of particles are simulated with a flow model in order to study two questions regarding the ice flow in Storglaciären. This model suggest that blue-ice structures observed on the ice surface did not originate as crevasses. The two applications of the model are: 1. To investigate advection and deformation of extensional crevasses in the upper accumulation area, too see whether they are the source of extensive arcuate blue-ice structures found at a lower altitude on the glacier surface. 2. To determine whether traces from crevasses originated in different areas would mix into each other during the transportation through the glacier.

The simulations of the particle paths and their deformation shows that: 1. Crevasses visible today in the accumulation area will emerge upglacier from the zone where the arcuate structures are found. Consequently, the model does not support explanation of the blue-ice arcs as closed or frozen water-filled crevasses. 2. Traces of crevasses from different crevassed areas will mix into each other when emerging at the surface. A discussion if changes in geometry of the glacier will affect the results gives that the dynamics in the glacier have not changed much in the uppermost 3/4 of the glacier since the mid-19th century.

Key words:

• Ice flow model
• particle paths
• englacial ice structures