A magma chamber is a large underground pool of molten rock found beneath the Earth's surface. The pressure from the magma can fracture the surrounding rock over time, creating pathways for the magma to travel through conduits and erupt at the surface in events like volcanic eruptions. When magma erupts at the surface, it is called lava and can take different forms like pahoehoe, a'a, or pillow lava depending on its viscosity and cooling conditions.

3. MAGMA
CHAMBER
A large underground pool of
liquid rock found beneath the
surface of the Earth. The
molten rock in such a
chamber is under great
pressure, and given enough
time, that pressure can
gradually fracture the rock
around it creating outlets for
the magma.

4. MAGMA
The form of
molten rock,
stored deep
within the
Earth’s surface

5. CONDUIT
The pipe that magma
travels through to reach
the Earth’s surface

6. CRATER
Roughly circular depression
in the ground caused
by volcanic activity. It is
typically a bowl-shaped
feature within which occurs a
vent or vents

7. CALDERA
Large
volcanic
craters

8. LAVA
A molten rock generated
by geothermal energy
and expelled through
fractures in planetary
crust or in an eruption,
usually at temperatures
from 700 to 1,200 °C.

9. LAVA
Bright yellow (over 1000 °C)
Orange (800-900 °C)
Dull red colors (600-700 °C)

11. PAHOEHOE
Southern Part of Hawai’i

12. PAHOEHOE
A smooth and continuous lava crust
Only low-viscosity lava can form pahoehoe
Lava flow that was originally pahoehoe may
transform into a’a lava
Pahoehoe is also known as ropy lava and it has
several more varieties named
Special conditions are needed for pahoehoe to
form: lava with low viscosity, low effusion rate,
and gentle slope.

13. A’A
Near the Western Coast of La Palma, Canary Islands

14. A’A
A rough rubbly crust of a lava flow.
Walking on it is very slow and potentially
dangerous even if one has good hiking boot.
The uppermost part of a’a lava is composed
of loose unstable blocks
Flow rates exceeding 5-10 m3/s clearly
favors the formation of a’a lava

16. BLOCKY
La Palma, Canary Islands

17. BLOCKY LAVA
 Common if the silica content of
lava is higher.
 They have irregular surfaces but
they contain larger lava blocks
with smoother sides and angular
edges.

18. PILLOW
Pillow lava near Fasoula. Troodos Ophiolite Complex, Cyprus

19. PILLOW LAVA
 A type of lava that is always associated
with water.
Form when lava flows out of the Earth’s
crust underwater
Usually demonstrate a convex upper and
concave or flat lower surface.
The surfaces of pillow lava are glassy.

20. VENTS
Spot in the Earth’s
crust where gases,
molten rock, lava
and rocks erupt

21. SILL
A flat piece of rock
formed when magma
hardens in a crack in
a volcano.

22. FLANK
The side of the
volcano

23. PARASITIC CONES
Cone-shaped
accumulation of volcanic
material that is not a part
of the central vent of a
volcano. It forms from
eruptions from fractures
on the flank of the
volcano.