1. Deformational Structures
- Load cast: are rounded or bulbous protrusions formed during compaction. Where these grooves and depressions become filled with sediment, especially if the surface is mud, the marks may be preserved.
- Convolute Bedding: appears as highly contorted, folded and disrupted layers.
- flame structure: deformed clay or silt laminations with curved, pointed ends that project into the overlying bed and resemble a flame blown in the wind.
2. Current Flow Structures
- Parallel Lamination : (where the upper and lower contacts are approximately parallel) can result from
- settling from suspension
- deposition in a low energy environment
- laminar flow (water flowing in a planar way)
- Ripple Marks : formed when the current flow energy increases.
- Cross Bedding : continuous erosion of the stoss side of the ripples and deposition on the leeward side causes
- Graded Bedding: As sediment is carried from a high energy environment into a low-energy environment, the heaviest particles will be the first to settle out, followed by progressively lighter and lighter particles.
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