Upper Devonian (Famennian) conodonts from radiolarian cherts, Loei Terrane, Loei Province, Northeast Thailand

Abstract

Conodonts from radiolarian cherts in the Loei Terrane of Loei Province, Northeast Thailand, include Palmatolepis triangularis, P. minuta minuta, P. minuta wolskae and polygnathids and indicate a Famennian crepida Zone age. These cherts are about 20 my younger than Givetian reef limestones and are unlikely to have been deposited in a major ocean but rather in a deep marine basin close to a volcanic arc.

Keywords

• conodont
• devonian
• palaeoenvironment
• tectonics
• indochina terrane
• chert.