Conodont biostratigraphy of the Hwajeol Formation (Upper Cambrian) in northern Taegaeg City, Korea

Abstract

The Hwajeol Formation (Upper Cambrian) is well exposed at northern Taebaeg City, Kangweon Province, mid-eastern Korea. The sequence of this formation includes, in ascending order: 1) alternation of thick massive and nodular limestones of Proconodontus and Eoconodontus notchpeakensis zones, 2) thick massive and nodular limestones and quartzite interval of Cambrooistodus minutus Zone, 3) nodular limestone interval of Cordylodus proavus Zone, and 4) interval of shale with sparse calcareous nodules grading up into quartzite bed of Fryxellodontus inornatus-Monocostodus sevierensis-Semiacontiodus lavadamensis Assemblage Zone. The Cordylodus proavus Zone ranges through the uppermost 30.9 m interval of the formation, and Fryxellodontus inornatus first appears at a horizon 23.4 m below the upper boundary. Conodont zones are correlated with equivalent zonal schemes of other parts of the world.