1.1 Changing Landscapes Flashcards
How does igneous rock form?
Form when magma (hot, molten rock in volcanoes) cools
What causes igneous rocks to have large crystals?
The slower they cool, the larger the crystals.
How does metamorphic rock form?
Made beneath the surface of the earth in ribbon like layers caused by heat and pressure.
How does sedimentary rock form?
Made out of sand, shells, pebbles and other materials that form layers and over time turn to rock?
Which type of rock are fossils generally found in?
Sedimentary
Describe metamorphic rock
Crystalline
Layers
“Squashed”
Give examples of igneous rock
Basalt
Pumice
Granite
Give examples of metamorphic rock
Slate
Schist
Marble
Give examples of sedimentary rock
Shale
Sandstone
Limestone
Chalk
What creates the characteristics of metamorphic rock?
Years of very high heat from magma and pressure under the earth.
What two types of rock do igneous form?
Intrusive
Extrusive
What is an intrusive rock?
Forms below the surface
What is an extrusive rock?
Forms above the surface
What is tectonic uplift/ destructive plate boundaries?
An oceanic crust slides under a continental crust, forcing the continental crust upwards and forming mountains
What is tectonic collision?
Collision zones form when two continental plates collide. Neither plate is forced under the other, and so both are forced up and form fold mountains.
What is tectonic rift/ constructive plate boundary?
the plates move apart from one another and magma rises up to construct new crust. The movement of the plates over the mantle can cause earthquakes.
Describe a characteristic of intrusive rocks
Large Crystals
What is a batholith
A large mass of intrusive igneous rock that forms and cools deep in the Earth’s crust
Define Scree
A mass of loose stones that form or cover a mountain slope
Define Tor
A large, free-standing rock on a gentle slope or hill summit
How do Tors form?
Created by weathering and erosion when a joint is unusually widely spaces and the core blocks survive weathering
What are Tors vulnerable to?
Frost action
What is the name given to a collapsed Tor?
Clitter
How do Limestone Pavements form?
Clints (huge slabs of rock) are separated by gaps weathered by run-off of acid rain
Define Limestone Pavement
Plateau of weathered limestone
Define Hydraulic Action
Water is forced into cracks in the rock and air is forced out explosively, breaking off pieces of the cliff
Define Abrasion
This is when pebbles grind along a rock platform, much like sandpaper. Over time the rock becomes smooth.
Define Attrition
This is when rocks that the sea is carrying knock against each other. They break apart to become smaller and more rounded.
Define Corrosion
When acid rain causes chemical weathering
Define Chemical Weathering
Acids in seawater slowly dissolve rocks
Define Biological Weathering
Roots of growing plants and burrowing animals or nesting birds can cause rocks to weather
Define Mechanical Weathering
Caused by repeated freezing and thawing of water in a crack or hole in the rock.
How does Freezing and thawing weather a rock?
(Mechanical weathering) water freezes and expands, putting stress on the rock, ice melts and the water sinks deeper into the rock and the process repeats.
Describe Rock Falls
Bits of rock fall off the cliff face, usually due to freeze thaw weathering
Describe Slumping
Saturated soil slump down a curved face
Describe Sliding
Saturated soil (filled with water) flows down a slope
What are the negative impacts of hard engineering?
- Not aesthetically pleasing
- Loss of habitats and organisms
- Starve areas further down the coast
Define Mass Movement
Movement of soil and rocks downslope due to gravity. Helped by weak rocks, steep slopes or rainfall
Define Soil Creep
Individual soil particles move slowly down a slope
Define Flows
Masses of rock/ soil (usually with water) flow in a line of liquid downhill
What is likely to occur if you have an overhang?
The overhang is likely to collapse
What is the Tees-Exe line?
A line which separates highland and lowland Britain
What is contact metamorphism?
Rocks, minerals and textures are changed, mainly by heat, due to contact with magma
What is regional metamorphism?
Rocks, minerals and textures are changed so that they have a squashed or foliated appearance due to high pressure
Define Suspension
Small grains and particles bounce in the sea
Define Erosion
The wearing away of rocks
Describe the rock cycle
Igneous is eroded and weathered to become sediment
Sediment is compacted and cemented into sedimentary rock
Heat and pressure changes sedimentary rock into metamorphic
Metamorphic rock melts to become magma
Magma cools to become Igneous Rock
What happens to an igneous or sedimentary rock under extreme pressure?
Heat and pressure
What happens to any type of rock if weathered/ eroded?
Becomes sediment
Name 3 upland features
Limestone Platform
Tors
Cove
Give an example of where limestone pavements can be found?
Grykes and Clints - Dartmoor
Give an example of where a tor can be found?
Bowerman’s Nose - Malham (Yorkshire Dales)
Give an example of where a cove can be found?
Malham Cove - Malham (Yorkshire Dales)
What rock are Grykes and Clints made of?
Hard Igneous rock - Granite
What rock is the Bowerman’s Nose made of?
Hard Sedimentary rock - Carboniferous limestone
What rock is Malham Cove made of?
Hard Sedimentary rock - Carboniferous limestone
What is a plane?
in rocks
Horizontal Lines
What is a joint?
in rocks
Vertical Lines
How do Limestone Pavements form?
Rainwater passes through the lines of weakness (planes and joints) in a rock, chemically weathering them. They widen and deepen.
How do Tors form?
A massive dome of magma develops and cools underground forming granite
Joints develop but make the rock vulnerable to freeze thaw action
Erosion and granite break down the rock into blocks surrounded by a clitter
