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Ripple marks are small waves of sediment formed by water or wind currents. They indicate the direction of flow and are commonly found in shallow water environments.

Desiccation cracks are similar to mud cracks but specifically occur in subaerial environments like river beds or flood plains where drying out and contraction of muddy sediment happens repeatedly.

Tool marks are grooves or scrapes on a sedimentary bedding surface produced by objects such as sticks, bones, or shells being dragged by currents. These indicate flow direction and are seen in river or deep-sea channels.

Fossils are the preserved remains or traces of ancient organisms. Their presence in sedimentary rocks indicates the past environments and biological activity. They are found in many depositional environments.

Graded bedding displays a vertical variation in particle size from coarse at the bottom to fine at the top. This is typical of a turbidity current depositing sediments in a deep marine environment.

Mud cracks are polygonal cracks formed due to the drying and contraction of mud in a variety of environments, including fluvial, lacustrine, and tidal flats.

Flute casts are scoop-shaped depressions found on the base of a sedimentary bed, formed by turbulent flows eroding the substrate. They are used to indicate flow direction and are common in turbidite sequences.

Cross-bedding refers to the internal sets of bedded sediments that are inclined at an angle to the main sedimentary layering. This structure is typically formed in river channels, deltas, and aeolian dunes.

Ooids are small, spheroidal, coated sedimentary grains, typically made of calcium carbonate. They form in warm, shallow marine waters with agitation, such as the Bahama platform.

Hummocky cross-stratification is characterized by undulating, cross-stratified layers with a somewhat random orientation, formed in a storm-influenced offshore marine environment.

Bioturbation structures are disturbances in sediments caused by the activities of organisms, which can obliterate sedimentary layering. These are common in continental shelf and deep-sea environments.

Raindrop impressions are small craters in sedimentary rocks created by the impact of falling raindrops. These are characteristic of terrestrial environments, such as floodplains or lake margins.

This pattern of cross-stratification where foresets are oriented in opposite directions suggests bidirectional currents, typical of tidal environments.

Stromatolites are layered bio-chemical accretionary structures formed in shallow water by the trapping, binding, and cementation of sedimentary grains by biofilms of microorganisms, especially cyanobacteria.