Seismic facies and architecture of ice-contact submarine fans in high-relief fjords, Troms, Northern Norway |
| |
| Authors: | ASTRID LYSÅ TORE O VORREN |
| |
| Institution: | Department of Geology, IBG, University of Tromsø, N-9037 Tromsø, Norway |
| |
| Abstract: | During the Late Weichselian, large marginal moraines were deposited in the Norwegian fjords. In Troms County these features are termed the Skarpnes and Tromsø-Lyngen moraines, respectively, and have been mapped from land into the marine environment where they were formed as ice-contact submarine fans. High-resolution seismic data from several fjords have been studied and reveal a typical sediment thickness of 150–320 m for these ice-contact systems. All of the ice-contact submarine fans were formed under similar climatic conditions, but display wide variation in geometry, architecture and seismic pattern. This variation is related to differences in sediment supply, the nature of the subsurface of the fan (e.g. position of thresholds), basin geometry and basin depth. Based on interpretation of the different seismic facies and the architecture of the fans, former ice-front positions have been suggested and a model has been presented for the formation of different types of ice-contact submarine fans dependent upon variation in local basin condition. |
| |
| Keywords: | |
|
|
