Antrim-Derry Plateau Sample answer Flashcards
1
Q
Example
A
giants causeway
2
Q
what are plateau?
A
◍ flat top upland areas made of basalt
◍ Fissure eruptions happen at constructive plates
3
Q
how was it formed?
A
◍ Euraisian and american pate collided
◍ basic lava [55% silica] flows out
◍ forming long narrow fissures/cracks
4
Q
over ling periods of time
A
◍ basalt is weathered and eroded to form laterite soil.
5
Q
giant’s causeway
A
◍ distinctive polygonal basalt columns
◍ 90 MYA
◍As plates continued to move away- led to new continental crust being formed and atlantic ocean opening
◍ All volcanic activity ceased
6
Q
Why hexagonal shapes?
A
◍Molten magma cooled
◍ contacted in a river valley
◍ forming 60,000 hexagonal basalt rocks
