These thick coal beds lie within Middle Miocene (? according to Witts et all 2011, IPA Proceedings) Warukin Formation in the Barito Basin. Not all coals are this thick . . . today we logged a section that included a 1 m thick coal overlain by a marine transgressive mud with abundant small aragonitic molluscs. The fauna was dominated by protobranch bivalves typical of very fine grained organic-rich marine muds. Sorry, no seagrasses here (yet).
Greetings from the Barito Basin! Aries, Ken and Jon followed Verbeek’s original (1875) geological map overlain onto Google Earth to find the Pengaron locality, from which a great fauna of corals and poorer molluscs was originally described. Just at the right point on the map – a river bank section - we found a thin series (4m) of massive, hard, bioclastic limestones and sands with corals, molluscs, algal balls, a shark tooth and vertebrate material abruptly and concordantly overlying thin-bedded silty mudstones.
