Question

Shield Volcano Lava Domes





Cinder Cone Composite Volcano
e. On the left side click “Inside a volcano”. Briefly describe the meaning of each


Magma Chamber:
Crater:
Main vent:
Secondary vent:
Ashes, clouds and cinders:
Layers of ash and lava:






f. Click “Next”. The effects of volcanic Eruptions. Describe 3 of each.
Negative Effects Positive Effects
1.
1.
2.
2.
3.
3.

Answer 1

e. Inside a volcano — brief meanings

- Magma chamber: A subsurface reservoir of molten rock (magma) that feeds eruptions.
- Crater: A bowl-shaped depression at the summit formed by eruptive activity or collapse.
- Main vent: The primary vertical conduit that connects the magma chamber to the crater and lets magma, gas, and pyroclastics escape.
- Secondary vent: Smaller outlets on the volcano’s flanks or base that release magma or gases when pressure finds another pathway.
- Ashes, clouds and cinders: Pyroclastic material produced by explosive eruptions — fine ash particles (very small), cinders (lapilli, pebble-sized fragments), and ash/gas clouds that rise and spread in the atmosphere.
- Layers of ash and lava: Alternating deposits of lava flows and pyroclastic material laid down by repeated eruptions; these layers build the volcano’s structure (common in composite/stratovolcanoes).

f. Effects of volcanic eruptions — three negatives and three positives

Negative effects
1. Destruction of life and property — lava flows, pyroclastic flows, and lahars can destroy towns, infrastructure, and cause fatalities.
2. Health and agricultural damage — ashfall causes respiratory problems, contaminates water, and buries or ruins crops and grazing land.
3. Climate and transport disruption — large ash and aerosol emissions can cool climate temporarily and force widespread air-traffic cancellations.

Positive effects
1. Fertile soils — weathered volcanic ash and tephra enrich soils with minerals, boosting long-term agricultural productivity.
2. Creation of land and resources — eruptions build new land (islands, lava plains) and concentrate mineral deposits (ore, pumice), and renew landscapes.
3. Geothermal energy and tourism — volcanic heat can be harnessed for power and hot springs; volcanic landscapes attract tourists and scientific interest.