Streams: Transport to the ocean Chapter 10: Streams: Transport to the ocean Hydrological cycle Stream profile and erosion Sediment transport and deposition Meanders Deltas

Some factors: amount of rainfall rate of evaporation runoff Streams 1) The hydrological cycle hydrological cycle: Continuous cycling of water between the atmosphere, oceans and land, due to gravity and energy from the Sun Some factors: amount of rainfall rate of evaporation runoff

The hydrological cycle oceans soil dams rivers evaporation mountains plants lakes snow rain The hydrological cycle 10 elements that are interrelated in the hydrological cycle

2) Stream profile and erosion Streams 2) Stream profile and erosion longitudinal profile: Steep gradient at head and almost flat at mouth. See Figs 14.13,14,15 Base level: The downward limit to which a stream can cut/erode host rock (“bottom of the hill”).

2) Stream profile and erosion Streams 2) Stream profile and erosion Over time streams can erode rock just like sandpaper

3) Sediment transport & deposition Streams 3) Sediment transport & deposition Stream transport mechanisms: in solution (dissolved in water) in suspension bed load (along bottom) See Fig. 14.2

3) Sediment transport & deposition Streams 3) Sediment transport & deposition Stream transport mechanisms: in solution (dissolved in water) in suspension bed load (along bottom)

3) Sediment transport & deposition Streams 3) Sediment transport & deposition Sediment deposition: channel deposits floodplain deposits alluvial fans & deltas Alluvial Fan (Death Valley, CA)

4) Meanders Floodplain: Stream channel deposits left by meandering rivers. Fig. 14.17

4) Meanders Oxbow lake Fig. 14.9

5) Deltas Delta: Distributaries: Salt marshes: Streams 5) Deltas Delta: depositional platform that forms at the mouth of a river Distributaries: smaller streams that branch off downstream Salt marshes: shallow bays between distributary channels Fig. 14.23

Streams Multiple choice   Which of the following terms describes a curved, coarse-grained deposit that forms on the inside curve of a stream? A. dune B. meander C. oxbow D. point bar

Curves and bends in a stream channel are called ______. Streams Multiple choice Curves and bends in a stream channel are called ______. A. alluvial fans B. braids C. deltas D. meanders

At a bend in a river, ______ occurs on the outside of the bend Streams Multiple choice   At a bend in a river, ______ occurs on the outside of the bend and ______ occurs on the inside of the bend. A. deposition. . . deposition B. deposition . . . erosion C. erosion . . . deposition D. erosion . . . erosion

Which of the following would be the most fertile area for crops? Streams Multiple choice   Which of the following would be the most fertile area for crops? A. a stream channel B. a floodplain C. a natural levee D. an uplands area away from the stream

Streams Multiple choice   Large, cone-shaped deposits of sediment at a mountain front are called ______. A. alluvial fans B. deltas C. natural levees D. terraces