Devonian/Lower Carboniferous stratigraphy, facies patterns and palaeogeography of Iran. Part I. Southeastern Iran

Abstract

The mountains N of Kerman in southeastern Iran are a key region for Devonian/Lower Carboniferous stratigraphy of a still poorly known segment on the northern margin of Gondwana and display a great diversity of neritic depositional environments. The hitherto applied subdivision into lithostratigraphic formations has been calibrated by means of conodonts and brachiopods allowing good correlations of 36 sections, the majority of them ranging from the top of the Cambrian or the Silurian into the Lower Permian. Upper Cambrian sandstones or Silurian carbonates are unconformably overlain by red siliciclastics of uncertain Early to early Middle Devonian age (Padeha Formation) which in turn pass into skeletal limestones (upper Middle Devonian to Tournaisian Bahram and Sardar Formations). The latter are erosionally capped by Permian platform carbonates (Jamal Formation). Facies patterns during 5 intervals from the Silurian into the Tournaisian show evolution from a carbonate platform and a siliciclastic shelf during the Silurian and the Early Devonian into shallow open marine embayments during the late Middle and Late Devonian, and a carbonate platform during the Early Carboniferous. Sharp boundaries between Upper Devonian facies belts appear controlled by synsedimentary
epeirogenic movements which may have been active since the Early Palaeozoic.