basalt
Basalt forms from cooled lava. This topic is part of Geology within Science & Nature. This page currently draws on 16 supporting questions, with answers and bonus facts available below.
basalt trivia questions
Basalt is what type of rock?
Answer: Igneous rock
Bonus fact: Basalt forms from cooled lava.
Basalt is most commonly formed from lava with what general composition?
Answer: Mafic
Bonus fact: Basaltic magma is relatively rich in iron and magnesium.
What famous geometric structures can form when thick basalt lava cools and contracts?
Answer: Columnar joints
Bonus fact: Cooling contraction can split basalt into polygonal columns.
Basalt is an example of what kind of igneous rock?
Answer: Extrusive
Bonus fact: Basalt forms from lava cooling at or near the surface.
Basalt columns form when lava cools and what?
Answer: Contracts
Bonus fact: Cooling contraction creates fractures.
What geometric pattern is common in columnar basalt?
Answer: Polygonal columns
Bonus fact: Many columns are roughly hexagonal.
Which famous Northern Ireland site is made of spectacular basalt columns?
Answer: Giant's Causeway
Bonus fact: Giant's Causeway formed from ancient volcanic lava flows.
Basalt usually forms when lava cools where?
Answer: At or near Earth's surface
Bonus fact: Basalt is a common extrusive igneous rock.
What process produced the regular columnar joints of the Giant's Causeway basalt?
Answer: Cooling and contraction of lava
Bonus fact: UNESCO documentation explains that slow cooling and contraction helped create the great number and regularity of the columns.
What type of lava commonly builds shield volcanoes?
Answer: Basaltic lava
Bonus fact: Low-viscosity basalt flows easily.
Where is a submarine volcano located?
Answer: Below sea level on the ocean floor
Bonus fact: USGS says submarine volcanoes are commonly composed of basalt.
The Giant's Causeway in Northern Ireland is made mainly of columns of which rock?
Answer: Basalt
Bonus fact: UNESCO describes roughly 40,000 basalt columns formed by ancient volcanic activity.