Sedimentary rocks

Weathering:

Breaking down of rocks with no movement 

Erosion:

the movement of rocks away from the outcrop (the source)

Transportation:

moving the sediments to a pacing/depression 

Deposition:

Accumulating the sediments on top of each other, adding more so the ones underneath get buried (burial) 

Lithification:

turning sediments into sedimentary rocks

Saltation:

the hopping of rocks as a form of movement 

Suspension:

carrying fine grains by water to the destination, which is the depression

Cementation:

when clastic sediments become hard rocks 

Compaction:

consolidating fine-grained sediments into rock

Quartz arenite:

when a rock is more than 90% quarts

Clastic sedimentary rocks:

mainly composed of material that has been transported as solid fragment (clasts)

Chemical sedimentary rocks

rocks that are dominated by components that have been transported as ions in solution (Na+, Ca2+, HCO3–, etc.).
 Limestone,
 Chert,
 Banded iron formation,
 Evaporites

Chemical Sedimentary Rocks: Limestone

• Almost all limestone forms in the oceans, and most of that forms on the
shallow continental shelves, especially in tropical regions with coral reefs.
• As the reef builds up, it is eroded by waves and currents to produce
carbonate sediments that are transported into the steep offshore fore-
reef area and the shallower inshore back-reef area.

• Limestone also accumulates in deeper water, from the steady rain of the carbonate shells of tiny organisms that lived near the ocean surface
• Tufa and travertine (which is less porous) are a variety of limestone formed when carbonate minerals precipitate out of ambient temperature water around hot springs.

dolomitization

• Dolomite/ Dolostone has been formed through magnesium replacing some of the calcium in the calcite in carbonate muds and sands.

Chemical Sedimentary Rocks: Chert

• Some marine organisms like radiolaria and diatoms, use silica, and when they die their tiny shells (or tests) settle slowly to the bottom where they accumulate as chert.
• Chert is deposited along with limestone in the moderately deep ocean, but the two tend to remain separate, so chert beds within limestone are quite common

Chemical Sedimentary Rocks: Banded iron formation (BIF)

• a deep sea-floor deposit of iron oxide that is a common ore of iron.
• BIF forms when iron dissolved in seawater and oxidized, becomes insoluble, and sinks to the bottom in the same way that silica tests do to form chert

Chemical Sedimentary Rocks: Evaporites

 formed when minerals, dissolved in water, begin to precipitate out of
solution and deposit at the base of the water body.

Trench basins:

• They form where a subducting oceanic plate dips beneath the overriding
continental or oceanic crust.

Forearc basin:

lies between the subduction zone and the volcanic arc, and may be
formed in part by friction between the subducting plate and the overriding
plate, which pulls part of the overriding plate down.

Foreland basins:

• they are not only related to volcanic ranges, but can form adjacent to fold belt
mountains like the Canadian Rockies

Rift basin:

• forms where continental crust is being pulled apart, and the crust on both
sides the rift subsides

accumulation of sediments and sedimentary rocks takes place according
to some important geological principles:

• The principle of original horizontality

• The principle of superposition

• The principle of inclusions

• The principle of faunal succession

Bedding:

• is the separation of sediments into layers that either differ from one another in textures, composition, colour, or weathering characteristics, or are separated by partings
• Bedding can form in almost any depositional environment.

Cross-bedding:

• is bedding that contains angled layers and forms when sediments are deposited by flowing water or wind
• it can provide information on the direction of current flows and, when analyzed in detail, on other features like the rate of flow and the amount of sediment available

• Ripples, which are associated with the formation of cross-bedding, may be
preserved on the surfaces of sedimentary beds.
• Ripples can also help to determine flow direction as they tend to have their
steepest surface facing down flow

Graded bedding:

• Graded bedding is characterized by a gradation in grain size from bottom to top within a single bed
• “Normal” graded beds are coarse at the bottom and become finer toward the top, a product of deposition from a slowing current.
• Some graded beds are reversed (coarser at the top), and this normally results from deposition by a fast-moving debris flow

• In a stream environment, boulders, cobbles, and pebbles can become
imbricated, meaning that they are generally tilted in the same direction

Mud cracks:

• they form when a shallow body of water (e.g., a tidal flat or pond), into which
muddy sediments have been deposited, dries up and cracks

Formation:

• is a series of beds that is distinct from other beds above and below, and is thick enough to be shown on the geological maps that are widely used within the area in question

• A series of formations can be classified together to define a group, which could be as much as a few thousand metres thick, and represents a series of rocks that were deposited within a single basin
• a formation might be divided into members, where each member has a specific and distinctive lithology.
• For example, a formation that includes both shale and sandstone might be divided into members, each of which is either shale or sandstone