Comparative study of the mineral composition of red clays of hungary [antikvár]

Introduction Different views on the formation, properties and distribution of red soils in Hungary have been published by several authors. Geologists took a stand on the origin of red clays. Lóczy (1886) described the red clay material as a variety of loess, a rock förmed by the deposition of wind-blown silt material. Loess förmed under drier conditions and red clay under more humid climatic conditions, though the age and origin of red clay and loess are identical. Treitz (1903; 1912) shared this opinion, stating that red clay, as a product of soilforming processes, was förmed from wind-blown material in the Quaternary Period. It is the B horizon of soils under forests established on loess, where the originál A horizon was eroded. Timkó and Ballenegger (1915) had similar ideas about these soils. A peculiar type of red clay is the clay soil förmed on rocks of volcanic origin (nyirok) in Tokaj-Hegyalja (foothills of the Tokaj mountain), which was first described by Szabó (1866) and characterized in detail by Ballenegger (1917), who reinforced Szabó's ideas. The clay soil (nyirok) at Tokaj-Hegyalja is a relic from the Tertiary Period förmed by the weathering of young, volcanic rocks and their tuffs from the Tertiary Period under subtropical climatic conditions. The term "nyirok", in a wider sense, is often used for red clays in generál. 0238-0161/97/$ 5.001997 Akadémiai Kiadó, Budapest