Geology and geoscience - introduction

Updated: Jun 27, 2025 06:20 GMT - refresh

Geology (from the Greek gea=earth and logos=study) is the natural science about the solid Earth, in particular the rocks it is composed of and the internal and external processes that shape it.

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Plate Tectonics

Introduction to Plate Tectonics
The Earth's upper, rigid layer is broken into several plates which are in constant motion to one another. Most earthquakes and volcanoes occur as result of these plate boundaries.

Volcano World

Find out about active volcanoes worldwide

Earthquakes

Earthquake monitor
Lists and maps of earthquakes in the world in near real time. Country lists, earthquake archive, and I-felt-it reports.

Volcanoes outside Earth

Volcanoes in the Solar System
The Earth is not the only place with volcanic activity. Active volcanism also occurs at at least 3 other bodies in our Solar System.

Igneous rocks

Igneous or magmatic rocks
The most primitive rock type forms when magma (molten rock) solidifies - either inside the earth (plutonic rocks) or during volcanic eruptions (volcanic rocks). A short overview.

Geology dictionary

Glossary of geologic terms
A growing list of often illustrated explanations and definitions of geological terms and keywords, with focus on volcanology and seismology.

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Guaranteed tours

1-17 Aug 2025: Volcanoes and Spices - Sulawesi/Halmahera (Indonesia)

1-14 Oct 2025: Desert, salt and volcanoes - Danakil desert (Ethiopia)

4-12 Oct 2025: From Stromboli to Etna - Sicily and Eolian Islands (Italy)

6-21 Oct 2025: From Krakatau to Bali - Java (Indonesia)

3-19 Nov 2025: Volcanoes and Spices - Sulawesi/Halmahera (Indonesia)

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More on VolcanoDiscovery

Volcano watching guide

How to watch volcanoes? Which volcano to choose? Some guidelines.

Erta Ale

Erta Ale volcano photos
During our numerous expeditions to Erta Ale and Dallol, we have documented the active lava lake and its surroundings and changes over the years.

Kilauea

Kilauea volcano photos
The most active volcano in the world with a record long lasting eruption since 1983: images of lava flows, lava lakes, explosions, lava meeting the ocean, aerials and more.

Eruption Specials

Volcano & eruption special tours
Tours dedicated to usually a single volcano currently in eruption. These trip, sometimes offered only last-minute through our newsletter, are among the most adventurous and most popular in our program.

Glossary