Table 1.

Lithofacies descriptions and environmental interpretations

Lithofacies assemblagesDescription and architectureTrace/body fossilsInterpretation
Facies Association 1: estuary fill and tidal strata
1.1: Sigmoidal, channelized sandstonesSigmoidal, lenticular, sandstone beds with concave-upwards, erosive bases, separated by persistent mudstone interbedsLockeia, PlanolitesTidal bars
Very fine to fine-grained sandstones with trough cross-stratification, planar cross-stratification and ripple laminations
Trough cross-beds ranging from 0.20 to 0.60 m thick and typically transitioning into ripple laminae
Rippled beds dominate and range from 0.10 to 2 m thick. Ripples are commonly draped with mudstones or carbonaceous material
Double mud drapes and flaser bedding common
Scattered weakly bidirectional palaeocurrents (dominantly SE-directed)
Beds amalgamate to form lenticular bar complexes up to 8 m thick
1.2: Carbonaceous shale and coal with minor sandstonesPredominantly carbonaceous shale and coal. Organic-rich throughout with common wood fragmentsThalassinoides, Planolites, Lockeia. Rare bivalvesBay fill including crevasse deposits
Minor, tabular sandstone beds range from 0.10 to 0.70 m thick
Sandstone beds have ripple laminations (some climbing), horizontal stratification, planar cross-stratification, convolute bedding, wood fragments and common mudstone drapes
1.3: Channelized, fining-upwards sandstones and inclined heterolithic strataMost commonly tabular/lenticular sandstone with erosive bases, lateral accretion sets and planar topsTeredolites, Planolites, Lockeia, Thalassinoides PsilonichnusTide-influenced channel fill
Fine- to coarse-grained, typically fining-upwards sandstone capped by mudstones or siltstones, up to 7 m thick
Mud rip-up clasts, ripples, planar cross-stratification, trough cross-stratification and lateral accretion surfaces. Convolute and flaser to wavy bedding also present
Bidirectional palaeoflow is dominantly towards the east (variable from NE to SE) with minor subordinate flow west
Some channel form deposits include inclined heteolithoc strata: rhythmically interbedded mudstones, siltstones and sandstones inclined 5–15° and laterally continuous over 10s–100s of metres
Mudstone drapes are pervasive and commonly organic-rich with plant material
1.4: Coarsening-upwards inclined heterolithic strataVery fine- to medium-grained rippled to trough cross-bedded sandstones, ranging from 0.02 to 0.70 m thickThalassinoides, Teredolites, Planolites LockeiaBayhead delta
Ripple-dominated, with flaser to wavy bedding, double mud drapes and climbing ripples common. Dominately north to NE palaeocurrent indicators
Coarsening- and thickening-upwards inclined, tabular to lenticular, heterolithic beds
Inclined heterolithic beds 5–12° cut laterally by erosive channel sandstones with up to 2 m relief
Interbedded and draped organic-rich mudstone and siltstone drapes persistent throughout
Wood fragments common and leaf fossils locally abundant within beds that cap the succession
Facies Association 2: coastal plain
2.1: Channelized, upwards-fining, cross-stratified sandstonesTabular to lenticular sandstones with erosive bases, lateral accretion sets and planar topsPlanolitesFluvial channels
Fine- to coarse-grained sandstones typically fining-upwards and capped by mudstones or siltstones
Sandstone is trough cross-stratified, planar cross-stratified, ripple and flaser laminated, with mud rip-up clasts, convolute bedding and wood fragments
Coarse-grained pebble gravel lags and trough cross-stratified sandstones with pebble foresets
Channels range from 1 to 6 m thick and are laterally continuous for 100s of metres
2.2: Horizontal, tabular beds of interbedded mudstones, siltstones with coal and carbonaceous shalesHorizontal, tabular beds of interbedded mudstones and siltstones, predominantly massive or laminated with minor mottling and/or nodular concretionsPlanolites present, but uncommonInterdistributary deposits
Organic-rich mud and carbonaceous shale common and these commonly grade vertically into coal
Coal beds range from 0.05 to 0.50 m thick (amalgamating to 1–2 m thick). Deposits are typically sulphur-rich and contain abundant plant material and leaf fragments
Very fine- to fine-grained sandstone beds range from 0.02 to 1 m thick with massive bedding, ripple laminations and horizontal stratification
Root traces commonly penetrate tops of sandstone beds and plant fragments are common