Advertisement.

EnchantedLearning.com is a user-supported site.
As a bonus, site members have access to a banner-ad-free version of the site, with print-friendly pages.
Click here to learn more.

ad
(Already a member? Click here.)


You might also like:
The Ring of FireVolcanoMother's Day Crafts, Cards, Activities, and WorksheetsToday's featured page: Tsunami Activities




Volcano Info
EnchantedLearning.com
Volcano Dictionary

Volcano Activities and Printouts
Types of Volcanoes The Ring of Fire
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Click on an underlined word for more information on that subject.


ocean

An ocean is a vast body of salt water. Oceans cover more than three-quarters of the surface of the Earth. The oceans on Earth include the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, and the Arctic Ocean. The ocean floors are composed mostly of basalt.
Obsidian

obsidian

Obsidian (also called Apache tears) is a volcanic glass that is usually black, but is occasionally red, brown, gray, green (rare), dark with "snowflakes," or even clear. This glassy, lustrous mineral is found in lava flows, and obsidian stones can be massive. Obsidian is formed when viscous lava (from volcanos) cools rapidly. Most obsidian is 70 percent silica. Obsidian has a hardness of 5 and a specific gravity of 2.35. The pin above is mahogany (brown) obsidian.


oceanic plates

The crust of the Earth is broken into plates. The plates are enormous chunks of rock that float atop the soft mantle. The plates are moving at a speed that has been estimated at 1 to 10 cm per year. Oceanic plates (those that are under the ocean) are thinner, younger, and denser than continental plates. These underwater plates are about 75 kilometers thick and are made of basalt rock. They are relatively young since plate formation (seafloor spreading) occurs at the margins of oceanic plates.

oceanography

Oceanography is the science that studies the physical geography of oceans.

outcrop

An outcrop is a place where bedrock is visible on the surface of the Earth.

outgassing

Outgassing is the release of gases into the atmosphere during volcanic eruptions. A lot of of our atmosphere (including water vapor, nitrogen, and argon) came from outgassing.


ozone

Ozone is a form of oxygen (O3); it consists of three connected oxygen atoms. Ozone is formed when oxygen molecules (O2) bonds are broken by high energy (bombardment by energetic electrons or high energy radiation).


ozone layer

The ozone layer is a region of the stratosphere which contains most (about 90%) of the Earth's atmospheric ozone. It is about10-25 miles (15-40 km) above the Earth's surface. The ozone layer shields the Earth from Ultraviolet B rays that come from the Sun. The ozone layer is becoming depleted, and there is an "ozone hole" over Antarctica.


Volcano Info
EnchantedLearning.com
Volcano

Volcano Activities and Printouts
Types of Volcanoes The Ring of Fire
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Click on an underlined word for more information on that subject.
If the volcano term you are looking for is not in the dictionary, please e-mail us.

Enchanted Learning®
Over 35,000 Web Pages
Sample Pages for Prospective Subscribers, or click below

Overview of Site
What's New
Enchanted Learning Home
Monthly Activity Calendar
Books to Print
Site Index

K-3
Crafts
K-3 Themes
Little Explorers
Picture dictionary
PreK/K Activities
Rebus Rhymes
Stories
Writing
Cloze Activities
Essay Topics
Newspaper
Writing Activities
Parts of Speech

Fiction
The Test of Time
iPhone app
TapQuiz Maps - free iPhone Geography Game

Biology
Animal Printouts
Biology Label Printouts
Biomes
Birds
Butterflies
Dinosaurs
Food Chain
Human Anatomy
Mammals
Plants
Rainforests
Sharks
Whales
Physical Sciences: K-12
Astronomy
The Earth
Geology
Hurricanes
Landforms
Oceans
Tsunami
Volcano
Languages
Dutch
French
German
Italian
Japanese (Romaji)
Portuguese
Spanish
Swedish
Geography/History
Explorers
Flags
Geography
Inventors
US History

Other Topics
Art and Artists
Calendars
College Finder
Crafts
Graphic Organizers
Label Me! Printouts
Math
Music
Word Wheels

Click to read our Privacy Policy

E-mail


Enchanted Learning Search

Search the Enchanted Learning website for:



Advertisement.



Advertisement.



Advertisement.


Copyright ©2001-2016 EnchantedLearning.com ------ How to cite a web page