4.1 Geology Past Processes Flashcards
What is an igneous rock
An igneous rock is a rock that has had partial heat ad pressure 350-450 mill hears old
andesite, basalt and obsidian
What is a sedimentary rock
formed by the deposition and subsequent cementation of the material
usually in lowland
Sandstone,limestone and slate
Compare metamorphic and igneous rock
Igneous rocks contain randomly arranged interlocking crystals. The size of the crystals depends on how quickly the molten magma solidified. The more slowly the magma cools, the bigger the crystals.
Earth movements can cause rocks to be deeply buried or squeezed. As a result, the rocks are heated and put under great pressure. They do not melt, but the minerals they contain are changed chemically, forming metamorphic rocks.
Compare differences between granite and carboniferous limestone
Granite is a light-colored igneous rock with grains large enough to be visible with the unaided eye. It forms from the slow crystallization of magma below Earth’s surface. Granite is composed mainly of quartz and feldspar.
Carboniferous Limestone is a sedimentary rock made of calcium carbonate. It is generally light-grey in colour, and is hard. It was formed in warm, shallow tropical seas teeming with life. The rock is made up of the shells and hard parts of millions of sea creatures
Compare formation of chalk and slate
Chalk rock (calcium carbonate), a pure form of limestone formed in warm, tropical seas about 100 million years ago
Slate was formed under low-grade metamorphic conditions( under relatively low temperature and pressure)
When did volcanoes shape upland UK
450 mill years ago lots of volcanoes mad sedimentary rocks in the uk
How did glacial erosion shape the uk uplands
Ice ages 1.t mill years ago to 12000 this eroded and deposited materials(moraines)
How was sedimentary rock formed along uk lowland
Sedimentary rocks are formed from sediments that have settled at the bottom of a lake, sea or ocean
Explain glacial erosion in the uk lowlands
Glaciers eroded many places and deposited lots of rocks and really good minerals, that is why lowland is so fertile.
How does scarp and vale form in uk lowland
The weald was once a dome of folded rocks forming an arch. Over time the dome eroded away removing chalk but leaving exposed chalk escarpments and the alternate strata of more resistant rock.
