An investigation of a Devonian/Carboniferous Boundary section on the Bolivian Altiplano

Abstract The Devonian/Carboniferous Boundary (DCB) interval is associated with mass extinction, isotope excursions and a short glacial episode. This study investigates how boundary extinction environmental change expressed in the high-palaeolatitudinal record of Bolivian Altiplano (western Gondwana). A latest Devonian early Carboniferous section has been investigated using sedimentology, palynology, total organic carbon bulk δ 13 C . Colpacucho Formation Late shelfal–marine siliciclastic sequence. It overlain area by unit coarse sandstones sandy diamictites, interpreted as glaciomarine. distinctive glaciomarine at least 7 km wide 60–120 m thick variably incisive basal contact (<100 m). very Famennian age stratigraphic equivalent proven glacigenic deposits across central South America. offshore marine Kasa overlies above flooding surface. DCB 12 this surface on last occurrence Retispora lepidophyta significant palynological assemblage changes. includes loss Umbellasphaeridium saharicum phytoplankton bioprovince, endemic to Gondwana. Marine terrestrial extinctions are synchronous 2 ‰ positive excursion be reflective changes matter delivery preservation during an stress. These results inform wider debates global DCB.