Depositional Environments

Agents of Rock Types / Structures / Location Environment Sediment Types Deposition Fossils 1. Alluvial Fan water, gravity poorly sorted rock and any detrital rock type Continental mineral fragments including arkose 2. Desert Dunes wind rounded, well-sorted sand- sandstone with cross Continental sized quartz bedding 3. Lake / Playa Lake water sand, mud; halite and gypsum sandstone, mudstone or Continental in dry climates shale; evaporites 4. Glacial ice, water poorly sorted deposits with any detrital, except arkose Continental variable grain size 5. River/Stream water sand in channels, mud and sandstones w/ ripple marks Continental plant materials outside & cross beds, mudrocks, possible coal / plant fossils 6. Beach water quartz sand and shell quartz sandstones with Transitional fragments shell fragments 7. Delta water sand in channels; mud and sandstones, shale, possible Transitional plant material coal / plant fossils 8. Tidal Flat water mud, calcite-rich mud Mostly fossiliferous Transitional mudrocks, limestone 9. Barrier Island water quartz sand and shell sandstones with shell Transitional fragments fragments 10. Shallow Marine water sand to mud to calcite-rich sandstone, mudrocks, Marine mud, shells limestone w/ marine fossils 11. Deep Marine water clay-sized fragments, claystone, chalk, chert Marine microscopic calcite & silica shells 12. Organic Reef water, corals calcite from abundant marine fossiliferous limestone Marine life, esp. corals 13. Submarine Fan water, turbidity graded beds, mud mudstone, sandstone Marine currents showing graded beds 14. Continental Shelf Marine water mud mudrocks 15. Lagoon water fossils, mud and calcite-rich fossiliferous shales and Marine mud limestones