From: Evolution of a Late Oxfordian: early Kimmeridgian carbonate platform, French Jura Mountains
Facies | Stratification and sedimentary structures | Textures and components | Depositional settings | |||
---|---|---|---|---|---|---|
Association 1 | ||||||
 F1.1 | Mudstone with marly intercalations | Dm-thick beds with cm-thick marly intercalations. Common bioturbation (Chondrites and Thalassinoides) | Mudstone (wackestone). Sparse fauna with echinoderms, undifferentiated bivalves, foraminifera (Lenticulina and Epistomina), siliceous sponge spicules, ostracods, and ammonites | Lower offshore | Outer shelf | |
 F1.2 | Mudstone with thin bioclastic intervals | Dm-thick beds. Planar lamination, mm- to cm-thick laminae with quartz grains and bioclasts. Common bioturbation (Chondrites and Thalassinoides) | Mudstone (wackestone). Low diversified fauna with foraminifera (Lenticulina, Epistomina), siliceous sponge spicules, ostracods, and ammonites | Lower to upper offshore transition | ||
Association 2 | ||||||
 F2.1 | Oncoid packstone | Dm-thick beds. Common (undifferentiated) bioturbation | Packstone. Abundant oncoids rich in nubecularids (types 2 and 3 of Olivier et al. 2011). Common echinoderms. Some bivalves, gastropods, brachiopods, ostracods, foraminifera (agglutinated, nodosarids, miliolids), serpulids, siliceous sponge spicules (rhaxes), and corals | Upper offshore | ||
 F2.2 | Coral-microbialite bioconstructions | Biostromal (dm-scale thick) or biohermal (m-scale thick) bioconstructions | Boundstone. Corals (mainly Enallhelia, Dimorpharaea and Thamnasteria) and microbialites (thrombolites and leiolites; cf. Olivier et al. 2011). Siliceous and calcareous sponges, nubecularids, bryozoans and serpulids | |||
 F2.3 | Oncoid marls | Cm- to dm-thick intervals. Common (undifferentiated) bioturbation | Packstone with abundant large oncoids (types 5 and 6 of Olivier et al. 2011). Abundant bivalves. Some echinoderms, ostracods, brachiopods, serpulids, foraminifera (nodosariids, Spirillina, miliolids, and agglutinated), siliceous sponge spicules (rhaxes), and corals | |||
 F2.4 | Bioclastic wackestone | Dm- to m-thick beds. Intense bioturbation | Wackestone (mudstone). Common bivalves, ostracods and siliceous sponge spicules (rhaxes). Some bivalves, echinoderms, and brachiopods. Rare gastropods, agglutinated foraminifera, miliolids, and serpulids | |||
Association 3 | ||||||
 F3.1 | Ooid grainstone | Massive (pluri-m thick) beds. Well sorted ooids. Cross bedding (herringbone cross-stratification) and planar lamination | Grainstone (packstone). Ooids (types 1 and 3 of Strasser 1986), micritic intraclasts and peloids. Common echinoderms, brachiopods, and bivalves. Some brachiopods and agglutinated foraminifera. Rare Nautiloculina, Lenticulina, miliolids, ostracods, bryozoans, serpulids and corals | Ooid shoals | Shoal complex | Shoreface (tide dominated) |
 F3.2 | Ooid-bioclastic grainstone | Massive (pluri-m thick) beds. Grains moderately sorted. Cross bedding | Grainstone. Ooids (types 3 and 4 of Strasser 1986). Common aggregates, intraclasts and peloids. Abundant crinoids and bivalves. Common serpulids. Some foraminifera (miliolids), bryozoans, gastropods, brachiopods, and Cayeuxia | Seaward shoal bars | ||
 F3.3 | Peloid-intraclastic packstone | Dm-thick beds. Cross bedding | Packstone. Abundant intraclasts and peloids. Common aggregates and Lithocodium-Bacinella oncoids (types 3 and 4 of Védrine et al. 2007). Abundant coral fragments, echinoderms, bivalves, gastropods, and agglutinated foraminifera. Some brachiopods, serpulids, and bryozoans. Rare miliolids, Nautiloculina and Lenticulina | Inter shoal channels | ||
 F3.4 | Coral reefs | M-scale coral patch reefs | Boundstone. Corals (mainly Thamnasteria, Isastrea, Microsolena) are the dominant element. Microbialites are mainly represented by leiolites | Intra shoal patch reefs | ||
Association 4 | ||||||
 F4.1 | Peloid-oncoid packstone | Dm-thick beds. Bioturbation is present | Packstones. Peloids and oncoids (made of Lithocodium and Troglotella). Common intraclasts and aggregates. Sparse ooids. Abundant foraminifera (miliolids, agglutinated). Common ostracods. Some echinoderms, brachiopods, bivalves, gastropods, and corals. Rare Nautiloculina, Lenticulina, siliceous sponge spicules (rhaxes), serpulids, and bryozoans | Back shoal | Shoreface (tide dominated) | |
 F4.2 | Peloid-oncoid packstone with stromatoporoids | Dm- to m-thick beds. Bioturbation is present | Packstone (wackestone) with abundant peloids. Common large oncoids (with a cortex made of Lithocodium, Bacinella, and Troglotella). Common stromatoporoids (Cladocoropsis) encrusted by Thaumatoporella (local bioconstructions?). Some foraminifera (miliolids, textulariidae, Nautiloculina, Lenticulina), echinoderms. Rare gastropods, brachiopods, ostracods, and corals | |||
 F4.3 | Peloid grainstone | Dm-thick beds. Well-sorted peloids. Planar and (low angle) oblique laminations. Some gypsum pseudomorphs and fenestrae | Grainstone. Peloids, some intraclasts, bivalves, echinoderms, foraminifera (agglutinated, miliolids, Nautiloculina). Rare gastropods, Lenticulina, and ostracods | Back shoal bars | ||
 F4.4 | Bioturbated mudstone | Dm-thick beds. Intercalations of cm-thick packstone beds (intraclasts and peloids). Intense bioturbation | Mudstone (wackestone, packstone). Common ostracods, agglutinated foraminifera, bivalves, siliceous sponge spicules (rhaxes), and echinoderms. Rare gastropods, brachiopods, and foraminifera (miliolids, textulariidae, and Lenticulina) | Interior platform | ||
 F4.5 | Bioclastic (marly) packstone | Dm- to m-thick limestone of marly limestone beds. Bioturbation (Thalassinoides) is present | Packstone (grainstone). Common intraclasts, aggregates, cortoids, peloids. Rare ooids. Common bivalves, echinoderms, gastropods, brachiopods, agglutinated foraminifera. Bivalves (Trichites, Pholadomya, Lucina), brachiopods (Terebratula), and gastropods (Harpagodes) in life position with complete shells. Some siliceous sponge spicules (rhaxes), foraminifera (Lenticulina, Nautiloculina, Molherina, textulariidae, miliolids), and ostracods. Rare bryozoans and serpulids | Shoreface (wave dominated) | ||
Association 5 | ||||||
 F5.1 | Biolaminites | Finely laminated with biofilm laminae and dinosaur tracks. Common mud cracks, ripples, and fenestrae | Dolomudstone. Some peloids and intraclasts. Rare foraminifera (Lenticulina, Nautiloculina, and agglutinated), and gastropods (Cariou et al. 2014) | Tidal flat | ||
 F5.2 | Sublithographic limestone | Finely laminated (biofilms?). Some desiccation cracks and rare fenestrae. Bioturbation is common | Mudstone. Common peloids. Rare gastropods and foraminifera (miliolids, agglutinated, and Lenticulina) | |||
 F5.3 | Black pebble limestone | Cm- to dm-thick beds. Common fenestrae, erosive surface with some (normally gradded) conglomerate | Grainstone (packstone) with abundant black pebbles. Abundant charophytes, some fragments of corals, stromatoporoids, and echinoderms (Bernier 1984) |