Changing That Landscape Of The Uk Flashcards
What are sedimentary rocks?
Sedimentary rocks are formed of small particles that have been eroded, transported, and deposited in layers, such as sandstone; or from the remains of plants and animals, for example limestone and chalk
What is chalk?
It a type of sedimentary rock that is made up of calcium carbonate, and is susceptible to chemical weathering
What is sandstone?
It’s a type of sedimentary rock that is made up of sand-sized grains cemented together. It can be hard and resistant to weathering but is permeable
What is igneous rock?
Igneous rocks are created by volcanic activity when magma or lava cools, forming rocks made of crystals that are usually hard. Examples are granite and basalt
What is granite?
It’s a type of igneous rock that is affected by chemical weathering. Granite landscapes drain badly, so tend to be boggy
What is basalt?
Basalt is a type of igneous rock that is grey made from very small crystals. Lava flows and cools to form basalt
What is metamorphic rock?
Metamorphic rocks are formed from other rocks changed by extreme pressure or heat. They are usually formed from layers or bands of crystals and are very hard. Examples of metamorphic rock include shale that is compressed into slate, or limestone that is transformed into marble
What is the geology of the Uk upland? (Describe the igneous and metamorphic rocks)
Upland areas are formed of harder resistant rocks which have eroded at a much slower rate. These include the igneous and metamorphic rocks found in Scotland, north wales, the Lake District and parts of south - west England. Around 300 million years ago tectonic processes caused molten magma, under intense pressure to rise through the earths crust. Some magma reached the surface of lava - whilst some magma cooled and solidified underground. Today these are high areas of relief example Dartmoor in Devon
Plate tectonics
Millions of years ago the uk was close to plate boundaries. Plate movements caused mountains (huge folds) and faults in the rocks. 520 million years ago two plates converged to form upland mountain landscapes - northern Scotland, the Lake District and north wales. 50-60 million years ago diverging plate boundaries cause the Atlantic Ocean to open. Rising lava produced the distinctive basalt geology of the Giants causeway
Distinctive landscapes
North-west of the Tees-Exe line the UK’s geology is largely igneous: rocks formed from magma and lava, associated with tectonic events. Long-extinct volcanoes form hills and mountains.
Basalt can form a very distinct landscape as the lava cools into polygon shapes: for example, the giants causeway in Northern Ireland and Fingal’s cave in Scotland.
Glacial erosion? (Upland)
Stickle tarn, in the north, is where a glacier formed during the ice age and carved out a corrie
Weathering? (Upland)
The crags are exposed rock faces. Weathering leads to rock fragments breaking off and falling to the base of the cliff to form a scree slope
Climate? (Upland)
High precipitation here means there is a lot of surface drainage over the impermeable rocks; there are many streams
Post-glacial river? (Upland)
The valley floor at the bottom is too wide for the stream to have eroded it. The flat bottom and steep sides shows that it is a U-shaped valley formed by a glacier
River erosion? (Lowland)
As the rivers meander, they have eroded a wide valley between low hills. The rivers transport slit eroded from the river channel