Facies Cryptic description Depositional processes Depositional environments Very well sorted. Desert dunes. Migration of straight crested mega ripples

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1 Very well sorted Travelled grate distance, effective sorting 5 medium-grained sandstone with well rounded grains; large scale high angle planar cross-beds. Migration of straight crested mega ripples Desert dunes Single, small, thirsty apeman fossil from WITS. Harsh dry continental conditions, wind Mudstone with lenses of gypsum, Low energy, evaporation thin carbonate interbeds, 4 mudcracks, Dessication planar and convolute laminations. slumping Playa lake Algae fossils occur High salt content, only limited species adopted to high salinity 3 Medium-grained sandstone Diamictite: Debris-flow or gravity of mass flow with planar and trough cross-beds clasts display no striations or facets No striations indicate not a tillite Low fan Middle fan Imbricate conglomerate. High energy 1 with lenses of evaporate minerals localised evaporation High fan Erosional base Erosion, higher energy Time gap in depositional history: Stable NA Full system in chronological order, start with time gap at base of facie 1 Desert warm environment

2 5 Pelbiosparmicrite Marine, limestone, warm, clean, shallow, close to deep waters that acts as food source. Oolites= 5%; intraclasts= 5%; pellets= 15%; fossils= 5%; sparite = 5%; micrite= 5%. The second part of the name is thus sparmicrite and the first part, pelbio. The full name of this rock is thus "pelbiosparmicrite". Coral reef 4 Mudrocks with varves Silt mud couplets, varves: suspension sedimentation Seasonal lake, energy variance 3 1 Imbricate conglomerate minor sand-filled channels Laminated mudrocks with dropstones Diamictite - clasts have scratch marks and facets High energy, directed waterflow Drop in energy, deposition of finer sediments Raft sediments Glacial movement, continental, poorly sorted sediments Glacial fluvial Marine glacial Sub glacial marine Time gap in depositional history: Between fasies 4 & 5 Facies 5, warm chemical conditions. Fasies 1-4 cold clastic conditions

3 4 Diamictite (clasts have facets and striations) Glacial movement, continental, poorly sorted sediments Sub glacial marine Immature arkosic pebbly sandstone Cold climate close to source not transported over great distance 3 Planar trough cross-beds Glacial fluvial/outwash fan Channel-fills Erosion and deposition, decrease in energy Minor cold-climate plant fossils Cold continental conditions a Laminated carbon-rich mudrocks Low energy, suspension sediments, plant-rich muds Flood plain Coal beds Burial, diagenesis of plant remains Medium-grained Mature wacke Transported over great distance or effective sorting b 1 Epsilon cross-beds Basal pebbles Followed upwards by plane beds Trough cross-beds and cross-laminae Laminated siltstone and mudstone Upward-coarsening succession Basal laminated siltstone followed by ripplemarked and planar cross-laminated fine-grained quartz wackes Minor marine fossils Medium-grained Planar and trough cross-bedded Orthoquartzites Lateral migration of point bars High energy with erosion potential High energy, upper flow regime Migration of Sinuous megaripples and ripples Low energy, suspension sediments Increase in energy Low energy migration of ripples Marine influence Travelled a great distance, reworked, effective sorting Channel/meandering river Marine, tidal trend, palaeocurrent strongly directional, delta Uppermost medium to coarse-grained orthoquartzites with channel-fills Planar and trough cross-beds Some plant fossils High energy mature sediments, erosion and deposition Shows signs of vegetation, rainfall, environment suitable for plant growth Time gap in depositional history: stable Sea level drop, regression Full system in chronological order Cold

4 9 Clean, well-rounded, well sorted Chemical sediments, travelled great distance, reworked Highly directional wind driven (coastal medium-grained sandstone dunes). Barrier island high angle, large scale planar cross-bedding Large straight crested megaripples, wind Thin laminated mudrock 8 with ripple marks Low energy, current/waves Tidal marine, upper tidal flat, shallow warm mudcracks and flaser beds Exposure dessication marine conditions marine trace fossils occur Marine environment Interbedded fine sandstone (with ripples and Tidal action, incoming tide strong, outgoing tide weak, cyclic alternating 7 planar cross-beds) and mudrocks energy Flaser beds and double-crested ripples Migration of ripples and megaripples Middle tidal flat, warm marine conditions many shallow marine invertebrate fossils Marine environment Medium-grained sandstone 6 through and planar cross-beds Lower tidal flats, warm marine conditions common shelled animal fossils Shallow marine, warm coastline, tidal palaeocurrent Coarse sandstone High energy 5 "Low-angle planar cross-bedding" common marine shell fossils and herring-bone cross-beds Is in actual fact upper flow regime planar beds, dipping towards the sea Shallow marine environment Beach. High energy coastline with random palaeocurrents, a warm setting Basal unconformity with pebbles and clay pellets High energy and erosion 4 Mudrocks with varves Silt mud couplets, varves: suspension sedimentation Seasonal lake, energy variance 3 Imbricate conglomerate Laminated mudrocks High energy, directed waterflow minor sand-filled channels with dropstones Drop in energy, deposition of finer sediments Raft sediments Glacial fluvial Marine glacial 1 Diamictite - clasts have scratch marks and facets Glacial movement, continental, poorly sorted sediments Marginal glacial marine Facies 9: Barier island, Facies 6-8 tidal lagoon, Facies 5: beach, facies 1-4: cold glacial Regresion between facies 7 & 8 Transgesion between facies 5 & 6 Time gap in depositional history: Between facies 4 & 5 cold in facies 1-5 and increase to warm in facies 9

5 Laminated siltstone and mudstone Low energy, suspension settling containing evaporite (halite) interbeds, Drying out, dessication and evaporation 4 some carbonate interbeds, Drying out, dessication and evaporation minor ripples and planar cross-laminations; Ripples and migration of straight-crested ripples Desert coastline some marine shelled animal fossils Difficult conditions and environment, shallow marine, high salt content, only little animal life lead to few fossils. Medium-grained quartz-rich sandstone, reasonably rounded and sorted; Travelled great distance, effective sorting mechanism planar and trough cross-bedding, Directed low sinuosity channels, 3 some channel-fills Erosion and deposition, energy change from high to low energy downstream desert river minor continental fossils; Difficult conditions and environment, shallow marine, only little animal life channel, seasonal lead to few fossils. evaporate matrix. Drying out, dessication and evaporation Alternating beds of unsorted clast-supported conglomerate High energy, chaotic transport, large clasts and imbricated better sorted conglomerates; high energy, lower than previous, directed waterflow Directed low sinuosity channels, matrix of sandstone and evaporites, Drying out, alternating between floods and droughts desert river/channel, seasonal minor continental fossils. On land, harsh continental conditions Well sorted, well rounded Long travelling distance quartz-rich fine sandstone Low to medium energy 1 with large scale, high angle planar cross-beds; Wind, straight crested megaripple migration Alluvial dunes (wind) matrix of sandstone consists of evaporites; Dry conditions one fossil of dehydrated UJ apeman Harsh dry continental conditions, wind None Possible between facies 3 & 4 Time gap in depositional history: None Warm desert coastline

6 Well sorted, well rounded Great travelling distance and efficient sorting fine- to medium-grained sandstone, Low to medium energy with evaporitic matrix Dessication 4a and large-scale high-angle planar cross-beds; Migration of straight-creasted megaripples by wind Aeolian sand desert very few fossils of small, mobile continental dinosaurs; Continental, diffficult conditions, isolated food supply, only the strongest survive lacks marine fossils. Emphasise continental Contains minor lenses (c. 00m wide and 5 m thick) Low energy, suspension settling, dessication of laminated, evaporite-bearing siltstone-mudstone Low energy, suspension settling, dessication 4b with minor ripple marks, Minor weak currents convolution of laminations Post deposition soft sediment deformations Playa lake and minor algae fossils. High salt, seasonal wet environments Lacks marine fossils Emphasise continental Interbedded fine-grained sandstones and mudrocks, Energy change, overall low energy with common flaser structures, Tidal action flat-topped and double-crested ripple marks, Tidal action 3 minor mudcracks, Dessication during low tide cycle alternation between low and high tides Middle tidal flats common shallow marine fossils in burrows. and Age of c. 70Ma. Banded iron formation; age 500 Ma. 1 Biopelsparmicrite; age 135 Ma. Warm shallow environment, fauna burrowed into small pools in the sand to live in this water in low tide BIFS, deep shelf or deeper marine environments, possible volcanic activities, biochemical sedimentation, most likely reducing than oxidising conditions Marine, limestone, warm, clean, shallow, close to deep waters that acts as food source. Oolites= 5%; intraclasts= 5%; pellets= 5%; fossils= 15%; sparite = 5%; micrite= 5%. The second part of the name is thus sparmicrite and the first part, biopel. The full name of this rock is thus "biopelsparmicrite" Deep shelf, more than 00m Coral reef Tectonic inplacement of facies between 1 & 3 Excluding facies Regression moving from deep to shallow marine Time gap in depositional history: possible between facies 1& and &3 warm excluding facies

7 large scale high angle planar cross-beds. Migration of straight crested mega ripples These structures form where the sediment is either deposited on a slight slope or where there is a shear stress on the material due to planar and convolute laminations. flow of overlying fluid (turbidites of slumping) with planar and trough cross-beds Planar trough cross-beds Epsilon cross-beds Lateral migration of point bars Trough cross-beds and cross-laminae Migration of Sinuous megaripples and ripples Planar and trough cross-bedded Planar and trough cross-beds high angle, large scale planar cross-bedding Large straight crested megaripples, wind 5. through and planar cross-beds 5. minor ripples and planar cross-laminations; Ripples and migration of straight-crested ripples 6.1 planar and trough cross-bedding, 6.1 with large scale, high angle planar cross-beds; Wind, straight crested megaripple migration 6.1 and large-scale high-angle planar cross-beds; Migration of straight-creasted megaripples by wind 6. flat-topped and double-crested ripple marks, Tidal action 6. Planar cross-beds will form by the migration of transverse dunes, straight-crested forms aligned perpendicular to the prevailing wind direction Planar cross-beds produce straight-crested forms Migrating straight crested ripples form planar cross-lamination fig 4.10 Sinuous or isolated (linguoid or lunate) ripples produce trough cross-lamination. trough cross-lamination produce Sinuous ripples. fig 4.10

Sediment and sedimentary rocks Sediment

Sediment and sedimentary rocks Sediment From sediments to sedimentary rocks (transportation, deposition, preservation and lithification) Types of sedimentary rocks (clastic, chemical and organic) Sedimentary