Can speed up by fluids very slow process as it can also involve the diffusion

Can speed up by fluids very slow process as it can

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Can speed up by fluids very slow process as it can also involve the diffusion of atoms through solid crystals. Neocrystallization yields quartz and feldspars in a gneiss. 10. Outwash style of rivers and streams The capacity of a stream refers to the total quantity of sediment it can carry. The material moved by streams is the sediment load. 1- Dissolved Load: ions from chemical weathering 2- Suspended Load: fine particles (silt and clay) in the water 3- Bed Load: larger particles roll, slide, and bounce along the bottom
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The competence of a stream refers to the max particle size it carries. Competence changes with velocity: -Slow water: can only transport fine sediments and solutes -Fast-flowing water: can move boulders and clasts Capacity and competence change with discharge: Stream discharge is the amount of water passing through a cross section of the stream in a given time, depends on such factors as watershed area and climate. -High discharge: large cobbles and boulders may move -Low discharge: large clasts are not moved A decrease in water velocity affects sediment transport. Competence is reduced, sediment drops out. Boulders, then gravels, then sands fill channel bottoms. Sands form inside banks. Silts and clays drap floodplains. How streams erode: streams scour, break, abrade and dissolve material. Fluvial deposits are sediments transported by streams. Alluvial fans (A) are conical, fan-shaped structures that build at the base of a mountain front. Sediments drop out rapidly with a change in stream gradient. The coarsest material is found near the mouth of the canyon; sediments grow fine and thin with distance. Braided streams (B) form where channels are choked by sediment. Flow is forced around sediment obstructions, and the diverging and converging flow creates sand and gravel bars. ** Meandering streams (C) evolve over time, becoming more sinuous (by cut-bank erosion and point-bar growth) before eventually being chopped off. The highest-velocity water erodes the outside of a bend, which called the cut bank. The inside of the bend (the point bar) is the site of sediment deposition. Fallen cut-bank material is transported away by flow (erosion). Deposition builds the point bar. Meanders become more sinuous with time (sine function form). The cut bank erodes, while the point bar accretes, which makes the curves become
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