Lerfall ved Roel, Innerøy.

Abstract

Innerøy is situated on the South-Eastern shore of Borgenfjord, a branch of Trondheimsfjord. The slip occurred in the afternoon of the 24th of April 1937. A road near the beach was destroyed by the slide over a distance of 130 m. Between the road and the beach the ground was pressed up to form a high wall, and on the other side of the road the ground showed crevices, the firm crust of the clay deposit being broken into turned and slidden flakes. At some places the crust had slid 8-10 m towards the fjord. The touched area covered 4-5000 sq. metres. Liquid clay was not visible, nor was any deepening in the ground here to be seen. A survey proved that the thickness of the clay deposit resting on rock amounted to 20 m. The underlying rock sloped steeply towards the fjord.