Sedimentary Landforms

Cards 1 – 14 → Sediment Transport & Formation Weathering, erosion, deposition, lithification, sorting, rounding, and grain size as energy indicators. Cards 15 – 20 → Sedimentary Structures Cross-bedding, ripple marks, graded bedding, mud cracks, and bioturbation — all clues to past flow and environmental conditions. Cards 21 – 28 → Environments & Processes Fluvial, deltaic, beach, and marine settings; turbidity currents and evaporites. Cards 29 – 35 → Composition & Identification Descriptions of clastic, chemical, and organic rocks — conglomerate, breccia, sandstone, shale, limestone, chert, coal. Cards 36 – 45 → Practice Quiz (Sedimentary Focus) Covers lithification, cross-bedding, energy levels, mud cracks, biological rocks, and identifying depositional structures.

1. Sediment – Definition

Loose particles of rock, minerals, or biological material that are transported and deposited by wind, water, or ice.

2. Sedimentary Rock – Definition

Rock formed from the lithification of sediments through compaction and cementation.

3. Weathering – Definition

The physical and chemical breakdown of preexisting rocks into smaller particles or dissolved ions.

4. Erosion – Definition

The removal and transport of sediments by wind, water, or ice.

5. Deposition – Definition

The process where transported sediments settle out of the transporting medium.

6. Lithification – Definition

The transformation of loose sediment into solid rock through compaction and cementation.

7. Compaction – Definition

Process where sediment grains are pressed together under pressure, reducing pore space.

8. Cementation – Definition

Minerals precipitate from groundwater and bind sediment grains together.

9. Clastic Sedimentary Rocks – Formation

Form from the accumulation of fragments of preexisting rocks (detritus).

10. Chemical Sedimentary Rocks – Formation

Form by precipitation of minerals from solution (e.g., limestone, halite).

11. Organic Sedimentary Rocks – Formation

Form from the accumulation of biological material such as plant remains (e.g., coal).

12. Sorting – Definition

Describes the uniformity of grain sizes in sediment; well-sorted = consistent sizes, poorly sorted = mixed sizes.

13. Rounding – Definition

Degree to which sediment particles have smooth edges; increases with transport distance.

14. Grain Size – Indicator

Indicates energy of the depositional environment; coarse grains = high energy, fine grains = low energy.

15. Sedimentary Structures – Definition

Features that form during or shortly after deposition, providing information about past environments.

16. Cross-Bedding – Definition

Inclined layers within a bed formed by wind or water currents; indicates direction of flow.

17. Ripple Marks – Definition

Small ridges formed by moving water or wind on a sediment surface.

18. Graded Bedding – Definition

Layer showing a vertical change in particle size from coarse at the bottom to fine at the top.

19. Mud Cracks – Definition

Polygonal cracks that form when muddy sediments dry and shrink.

20. Bioturbation – Definition

Disruption of sediments by organisms such as worms or roots.

21. Fluvial Environment – Definition

River and stream settings where sediments are transported and deposited by running water.

22. Deltaic Environment – Definition

Where a river meets a standing body of water; sediments form deltas with layered deposits.

23. Beach Environment – Definition

Wave-dominated setting where sand-sized sediments accumulate along shorelines.

24. Deep Marine Environment – Definition

Fine-grained clay and planktonic material settle slowly; often forms shale or ooze.

25. Turbidity Current – Definition

A dense, fast-moving underwater current carrying sediments down continental slopes.

26. Turbidite Deposit – Definition

A graded bed formed by turbidity currents, coarse at base, fine at top.

27. Continental Shelf Deposition

Mix of clastic and chemical sediments in shallow marine environments.

28. Evaporite – Definition

Chemical sedimentary rock formed by evaporation of water, leaving mineral deposits like halite or gypsum.

29. Conglomerate – Description

Clastic sedimentary rock with rounded gravel-sized clasts; indicates high-energy environments like rivers.

30. Breccia – Description

Clastic sedimentary rock with angular gravel-sized clasts; indicates deposition near source area.

31. Sandstone – Description

Medium-grained clastic rock made of sand-sized particles; indicates moderate energy environments.

32. Shale – Description

Fine-grained clastic rock formed from mud or clay; deposited in low-energy settings like deep water or floodplains.

33. Limestone – Description

Chemical or biological sedimentary rock composed mainly of calcite (CaCO₃).

34. Chert – Description

Microcrystalline quartz formed by chemical precipitation or replacement; often found with limestone.

35. Coal – Description

Organic sedimentary rock formed from compressed plant material in swampy environments.

36. Practice Quiz – Which process compacts sediments into rock?

Compaction and cementation (lithification).

37. Practice Quiz – Which environment forms cross-bedding?

Desert dunes or river channels.

38. Practice Quiz – What indicates high energy transport?

Coarse-grained, poorly sorted sediments.

39. Practice Quiz – What do mud cracks indicate?

Periodic drying of wet environments, such as tidal flats.

40. Practice Quiz – Which rock forms from biological remains?

Coal or some limestones.

41. Practice Quiz – Which feature shows current direction?

Cross-bedding or ripple marks.

42. Practice Quiz – How does grain size relate to energy?

Larger grains = higher energy, smaller grains = lower energy.

43. Practice Quiz – Example of a chemical sedimentary rock?

Halite or limestone.

44. Practice Quiz – What rock forms from fine clay particles?

Shale.

45. Practice Quiz – What structure forms from underwater avalanches?

Graded bedding (turbidites).