Wedge- and fold-like diagenetic disturbances in quaternary sediments and their paleogeographic significance

Abstract

This paper examines the origin of wedge- and fold-like disturbances in Quaternary sediments, a problem historically tied to the concept of the periglacial zone. The author traces the evolution of views on these deformations, noting the early controversy between two main hypotheses: thermal convection (Brodel-Böden) and frost-heaving. Over time, the frost-heaving theory, which attributes these disturbances to cryoturbation, gained wide acceptance. The paper introduces a new perspective, arguing that many of these deformations, especially the wedge-like structures, are not solely of cryoturbational origin but are also the result of diagenetic processes, particularly the transformation of cryogenically formed structures after the ice has melted. This new hypothesis suggests that certain periglacial landforms are not solely a product of cryoturbation but are also shaped by post-depositional changes, a concept with significant implications for paleogeographic reconstructions.