Spor etter stormbølgene? : en geomorfologisk studie av tre blokkavsetninger ved kysten av Roan, Sør-Trøndelag
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- Institutt for geografi 
The focus of this thesis is the origin and morphogenesis of three assemblages of coarse boulders similar to coarse beach deposits, located between 7-23 meters above sea level at the coast of Roan, Sør-Trøndelag. In coastal geomorphology, there is a growing interest in storm wave entrainment, transport and deposition of boulders along rocky coasts. Yet, similar objectives have not been explored along the Norwegian coast. This thesis addresses the possibility of storm wave origin for the landforms in question, by testing the hypothesis that they are primarily deposited by storm waves when the area was in the tidal zone approximately between 5100 and 1800 years ago, and that they can be defined as boulder beaches. Morphological and sedimentary qualities such as overall shape and distribution of material, packing, angularity and shape are examined both by field observation and by the use of LiDAR-data. Field measurements and LiDAR-data are also used to measure boulder size and a-axis orientation for boulders ≥2m. Transport equations developed by Nott (2003) are used to estimate the necessary storm wave heights for mobilizing the 15 largest boulders at each site, and the results are compared to instrumental and significant wave heights recorded during the Dagmar storm in 2011. The results show that many of the morphological and sedimentary qualities from the three study-sites match descriptions of storm wave deposits, and two of the three deposits show distinct similarities to boulder beaches. According to the results from Notts equations most of the material at these two sites could have been mobilized by storm waves, and only the deposition of the largest megaclasts cannot be explained by storm wave transport. The wave height results from the last study-site show that larger waves would have been necessary to mobilize the material in this deposit, and the results show a larger influence of other processes here, than at the other study-sites.