Volcanoes

Question 1

Lava

Answer 1

Aa lava
Pahoehoe lava

Question 2

Pyroclastic materials

Answer 2

Fragments of rock erupted by volcano

Question 3

Volcanic gasses

Answer 3

Gasses are held in molten rock by confining pressure (like carbon dioxide held in drink cans)
Upon eruption pressure is lessened and gasses released
Most abundant volcanic gas - water vapor

Question 4

Plate motions

Answer 4

Provide the mechanisms by which volcanoes form

Question 5

Convergent plate volcanism

Answer 5

Subducting plate melts and produces magma

Question 6

Divergent plate volcanism

Answer 6

The greatest volume of magma erupts along divergent plate boundaries associated with seafloor spreading

Question 7

Earth’s Dynamic Surface

Answer 7

200 years ago, most believed mountains, lakes, and deserts were permanent features of an earth that was thought to be no more than a few thousand years old

Question 8

Processes that result in dynamic surface

Answer 8

Internal processes derive their energy from earth’s interior - plate tectonics

Question 9

External processes

Answer 9

Weathering - physical break down and chemical alteration of rocks at or near earth’s surface
Mass movement - transfer of rock and soil downslope under the influence of gravity
Erosion
Mechanical weathering - physical forces that break rock into smaller and smaller pieces without changing the rock’s mineral composition