New constraints on the Upper Permian and Lower Triassic geomagnetic polarity timescale from the Abadeh section (central Iran)

Yves Gallet (1) , Leopold Krystyn (2) , Jean Besse (1) , Luc-Emmanuel Ricou (1) , Abdolah Saidi (3)

1 IPGP - Institut de Physique du Globe de Paris
2 Institute of Paleontology
3 Geological Survey of Iran

We present the magnetostratigraphy of the Abadeh section (central Iran). Thermal demagnetization shows two magnetic components: one at low unblocking temperatures, which corresponds to a present day-field direction, and another at high temperatures. This second component, which contains both polarities, is interpreted as a primary magnetization acquired during sediment deposition at a paleolatitude of about 7.7øS. A sequence of 14 magnetic polarity zones is obtained in the intervals during the Upper Dzhulfian-Lower Changhsingian (Upper Permian) and during the Griesbachian (Lower Triassic). Combining data from south China, Canada, Pakistan, and Iran, we propose a composite (but still uncomplete) Upper Permian and Lower Triassic geomagnetic polarity timescale.

Domaines: Géophysique [physics.geo-ph]; Stratigraphie

Yves Gallet, Leopold Krystyn, Jean Besse, Luc-Emmanuel Ricou, Abdolah Saidi. New constraints on the Upper Permian and Lower Triassic geomagnetic polarity timescale from the Abadeh section (central Iran). Journal of Geophysical Research, 2000, 105, pp.2805-2815. ⟨10.1029/1999JB900218⟩. ⟨insu-01863484⟩