MAGNETOSTRATIGRAPHY OF THE HETTANGIAN LANGMOOS SECTION (ADNET, AUSTRIA) - EVIDENCE FOR TIME-DELAYED PHASES OF MAGNETIZATION

Study of the magnetostratigraphy of the earliest Jurassic (mainly Hett angian) section of Langmoos near Adnet in Austria (Northern calcareous Alps) provides a sequence of 10 magnetic polarity intervals. These in tervals are often evident in the natural remanent magnetization. Howev er, rather than a true magnetostratigraphic sequence, palaeomagnetic a nalyses reveal evidence for successive phases of magnetization within the section. Evidence includes (1) changes in lithology associated wit h changes in magnetic polarity, (2) different combinations of componen ts of both polarities, and (3) largely non-antipodal directions. Consi dering the palaeomagnetic directions, we suggest that the apparent mag netostratigraphy is the result of two or three phases of magnetization which occurred at different stages of the tectonic emplacement of the Northern Calcareous Alps.