Registration of rock blocks movements using dendrogeomorphic methods: new methodical approach in a case of localities in the Moravskoslezské Beskydy Mts.

Abstract

This study proposes a new systematic procedure for the dendrochronologic dating of the movement (esp. lateral spreading, backward rotation and toppling) of large boulders with precision to seasons. The methodology is based on the dendrogeomorphic analysis of trees which have been deformed by tilting blocks. Based on the research carried out in four localities within the Moravskoslezské Beskydy Mts, we have identified 22 event years revealing deformations caused by blocks. The interaction between tree stems and tilting blocks is represented by various macroscopic changes as well as growth disturbances within tree-ring series. These most frequently involve tangential rows of traumatic resin ducts and abrupt growth suppression/release. An analysis of meteorological characteristics identifies potential triggers of movements featuring especially summer heavy rainfalls.