New aspects of the interpretation of the loess magnetic fabric, Cérna Valley succession, Hungary

Abstract

AbstractAnisotropy of magnetic susceptibility (AMS) is a frequently applied method in sedimentology, especially in the determination of the orientation of transport processes. We present an analysis of magnetic fabric (MF) studies on loess. New aspects of fabric development reveal: i) The deposition of the aeolian sediments was controlled by gravity, low-energy transport and local geomorphology, hence no clarified wind direction can be defined. ii) The influence of phyllosilicates is also significant among the magnetic components. iii) While the primary MF is relatively well-defined, the secondary MF is influenced by several processes. The analysis of stereoplots combined with the q—β diagram and photostatistics showed encouraging results during the characterization of various secondary MF such as redeposited MF and pedogenic fabric. iv) Changes in processes from aeolian to water-lain deposition and the increasing transportation energy were reflected by the connection between AMS and observed micro-scale sedimentary features. v) A relationship was obvious between the degree of pedogenesis and the transformation of sedimentary MF into a vertical MF typical for paleosols. vi) The significant role of very fine grained magnetite on the formation of inverse MF could not be excluded.