Geomorphology Flashcards
Strata
Anotehr term for layers of rock
Stratified rock
Rock composed of layers of strata
Bedding plane
Planes separating layers of rock
guillies
Narrow, long areas of erosion on a slope
Plateau
A large, flat high lying landform
Sheet wash
Rainfall flowing over land as a sheet
Lava flow
Lava pours onto surface, cools and solidifies
How does horizontally layered rock form - two ways
1.Sediments deposited on top of each other consolidate + forms rock
2.Large scale lava flow
Landscapes associated with horizontal strata *4
*hilly landscapes
*basaltic plateaus
*canyon landscape
*karoo landscape
Hilly landscapes and basaltic plateaus provide…….. resistance to erosion
Uniform- same speed
Canyon landscapes provide……. resistance to erosion
Alternating
Explain how hilly landscapes are formed
Sedimentary strata with uniform resistance form a steep hilly landscape
Influence of humid areas on hilly landscapes *2
*rounded slopes because of sheet wash
*rainfall removes surface material on slopes
Influences of dry areas on hilly landscapes *
*steep with sharp ridges bc no sheet wash
*hills with narrow guilles form in arid climates
What are hilly landscapes in arid climates called
Badlands
Outburst aka
Successive fissure eruption
What do outbursts cause
Lava to flow on the surface
Explain how basaltic plateaus form *2
*lava flows on the surface bc of outbursts
*a layer of basalt if formed - provides uniform resistance and gives rise
Has uniform resistance
What does vertical erosion in basaltic plateaus cause
Deep, narrow gorges
What is tectonic uplifts due to
Crustal forces
What erosion takes place in canyons
Vertical
How does a plateau form a canyon
Tectonic uplifts
Influence of humid climate on canyons
*water erodes slopes - rounded and gentle
Influence of dry areas on canyons
*sharps ridges and steep uneven badlands - lack of rainfall
Dolerite still
Horizontal layer of igneous rock formed along a bedding plane
Where do Karoo landscapes form from
Canyons
How do Karoo landscapes form
Canyon floor gets wider, plateau surface gets smaller
Why do plateaus hold original height
Resistant cap rock
Order that plateau erodes in *4 - Karoo landscape
Mesa > butte > pointed butte > conical hills
Mesa
Flat topped mountain with greater width than height
Butte
Flat topped mountain with greater height than width
Pointed butte
Narrow hill with sharp peak
Conical hill
Small pointed hill
Conical hill
Small pointed hill
Scarp retreat
Erosion causing loss of width but not height
As plateus narrow, canyon floors become…
Wide
How are hilly landscapes utilised
*in humid climates slopes are steep + chemical erosion creates fertile soil - farming
Why can’t farming be done in high altitudes of basaltic plateaus *2
*cold temperatures
*rugged slopes bc vertical erosion
Why can farming be done in lower altitudes of basaltic plateaus *2
*not as cold
*basalt weathering creates fertile soil
Chemical weathering
Decomposition of rock due to chemical processes
Water, carbon dioxide, oxygen
Mechanical weathering
Decomposition of rock due to extremes in temperature
Utilisation of Canyon
Tourist attractions
Utilisation of Karoo *2
*Maybe farming, but precipitation is an issue
*Attractions
Inclined strata formation
Sedimentary layer is uplifted and tilted