Meliat Formation (Middle Miocene)
Description: Interbedded sandstone, claystone and shale with coal intercalation.
Tabul Formation (Late Miocene)
Description: Interbedded claystone, mudstone, sandstone, limestone and coal in the upper part.
Sajao Formation (Plio-Pleistocene)
Description: Quartz sandstone, claystone, siltstone, coal, lignite and conglomerate.
Lengap Formation (Late Miocene)
Description: White tuff, chalky, conglomerate coarse grain sandstone, thick coal seams.
Latih Formation (Miocene)
Description: Quartz sandstone, claystone, siltstone and coal in the upper part, intercalation sandy shale and limestone on the lower part, coal seam 0.2 to 5.5 meter thick.
Labanan Formation (Late Miocene – Early Pliocene)
Description: Alternation of polymict conglomarate, sandstone, siltstone, claystone, intercalation of limestone and coal seam (20 to 150 cms).
Kayan Formation (Upper Oligocene)
Description: Quartz sandstone, shale, siltstone and conglomerate intercalations, silicified wood and minor coal .
Ketungau Formation (Upper Eocene)
Description: Sandstone and mudstone, thin coal seams in upper part.
Selangkai Formation (Upper Cretaceous)
Description: Shale, mudstone, sandstone, conglomarate, fossiliferrous limestone, rare coal genrally carbonaceous or calcareous.
Kuaro Formation (Eocene)
Description: Shale sandstone, conglomerate, claystone, breccia, marl and limestone intercalated with coal.
Karangan Formation (Eocene)
Description: Conglomerate, sandstone, claystone intercalated with limestone and Lignite.
Kampung baru Formation (Pliocene)
Description: Sandy clay, marl and sand intercalated with coal and tuff .
Tebidah Formation (Lower Oligocene)
Description: Feldspathic lithareanite interbedded with mudstone and siltstone, thin coal seams in places.
Kantu Formation (Upper Eocene)
Description: Sandstone with minor conglomarate, ,mudstone in lower part, interbedded sandstone, siltstone, grey or red mudstone in upper part, locally coal seams.
Silat Shale (Upper Eocene to Lower Oligocene )
Description: Blake carbonaceous mudstone, shale, minor dark siltstone, fine to medium grained sandstone, at places thin coal seams.
Kelinjau Formation (Miocene)
Description: Mudstone, minor sandstone and volcano clastic rock, in places silicified wood and intercalations of coal.
Mentemoi Formation (Eocene to Oligocene)
Description: Lower part is sandstone, upper part is arokosic sandstone, fine to coarse grained reddish. Locally intercalated with quartz conglomerate and claystone with thin coal seams.
Batuayau Formation (Late Eocene)
Description: Sandstone, mudstone, siltstone, commonly carbonaceous, in places intercalation of coal and lignite
Anggota batugambing peanut Formation (Late Oligocene)
Description: White and ghrey limestone, medium to coarse grained, rich in large forams, algae and coal.
Purukcahu Formation (Late Oligocene to Early Miocene )
Description: Fossiliferrous claystone, dark grey siltstone containing small lenses and thin layered vitrinite coal.
Pulaubalang Formation (Middle Miocene)
Description: Quartz sandstone and grey wacke, claystone with limestone intercalation, tuff and coal.
Balikpapan Formation (Middle to Late Miocene)
Description: Quartz sandstone and claystone with intercalation of siltstone, shale and limestone with lignite intercalations.
Pamaluan Formation (Late Oligocene to Early Miocene )
Description: Sandstone with intercalation of claystone, shale, marl, siltstone, tuff, coal, Iron oxide and lenses of limestone, claystone with sandstone intercalation, thin coal seams in the lower sequence (25 to 75 Cms), in the upper part of sequence coal seam thickness is 0.5 to 5 Mts.
Montalat Formation (Oligocene)Description: Cross bedded, white quartz sandstone, locally calcareous interbedded by siltstone, shale and coal.
Warukin Formation (Lower Miocene)
Description: Sandstone (Tuffaceous and calcareous), siltstone and claystone interbedded with coal beds (0.3 to 2 mts)
Dahor Formation (Middle Pliocene to Pleistocene )
Description: Quartz sandstone with coal beds (0.3 to 3 Mts) with in coarse sandstone layers.
Berai Formation (Middle to Late Oligocene ) Description: Limestone interbedded by claystone, marl and coal.