Chapter 16 - Weathering and Mass Movement Flashcards
weathering
the process by which solid rock is dissolved and broken apart into smaller fragments
erosion
the scouring and stripping away of rock fragments loosened by weathering
sediment transport
the movement of rock fragments (sediments) that have been weathered and eroded
deposition
occurs when sediments in transport are lad down
denundation
the lowering and wearing of Earth’s surface
physical weathering
breaks down rocks into smaller pieces/clasts without altering the chemical makeup of the rock
exfoliation
a process where joints form parallel to the rock surface, creating sheet-like slabs of rock resembling the layers of an onion
frost wedging
a process by which water in a joint in rock freezes and expands, causing the opening to grow
salt weathering
a process in which salt crystals grow in pore spaces within a rock and exert pressure as they grow
tafoni
rounded pits or cavities on the surface of a rock that form through salt weathering
root wedging
occurs when plant roots that are seeking water grow into joints
chemical weathering
changes the minerals in rock through chemical reactions involving water
carbonation
a chemical weathering process in which carbonate rock such as limestone is dissolved in a carbonic acid solution and carried away
spheroidal weathering
the process of weathering along the edges and corners of a rock, causing them to become rounded over time
karst
refers to an area dominated by weathering of carbonate rocks, usually limestone
dissolution
the general process in which a mineral completely dissolves in water
sinkhole
a depression in Earth’s surface that results from dissolution of carbonate rocks underground
sinkhole lakes
sinkholes filled with water
collapse sinkhole
forms where the ceiling of a subterranean cave has collapsed
disappearing streams
surface streams that are found in karst regions that usually flow for short stretches before disappearing into the ground
speleothems
a cavern formation that forms through precipitation of calcium carbonate
stalactites
formations that grow from the ceiling downwards
stalagmites
formations that grow from the cave floor upwards
limestone column
a cylindrical dripstone that results when a stalactite joins with a stalagmite
mass movement
the movement of rock, soil, snow, or ice downslope via gravity (such as a landslide)
soil creep
the imperceptible downslope movement of soil and regolith as their volume changes in season expansion-contraction cycles
solifucation
a special type of soil creep where freeze-thaw expansion-contraction cycles cause the soil to flow slowly downslope in overlapping sheets
slump
a type of mass movement in which regolith detaches and slides downslope along a spoon-shaped plane and comes to rest more or less as a unit
landslide
a general term for the sudden and rapid movement of rock or debris down a steep slope
mudflow
a fast-moving flow composed of fine-grained material mixed with water that form mud
debris flow
when a fast-flowing slurry of mud is mixed with large objects, such as rocks and vegetation
rock slide
a landslide that consists predominately of rocks and broken rock fragments
debris slide
consists of regolith and other material, such as soil and trees; also called debris avalanche
avalanche
a turbulent cloud of rock debris or snow that is mixed with air and races quickly down a steep slope
avalanche chutes
canals in which snow and debris avalanches regularly move through
rockfall
occurs when rocks tumble off a vertical or nearly vertical cliff face
talus
the pieces of angular broken rock that accumulates at the angle of repose at the base of a steep slope of cliff
talus cones
accumulation of talus at the base of rockfall chutes in cone-shaped piles
talus apron
forms where two or more talus cones merge at the foot of a cliff
