Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Volcano
| Term | Definition |
|---|---|
| Magma | hot fluid or semifluid material below or within the earth's crust from which lava and other igneous rock is formed by cooling. |
| Volcanism | volcanic activity or phenomena. |
| Lava | hot molten or semifluid rock erupted from a volcano or fissure, or solid rock resulting from cooling of this. |
| Hot Spot | an area of volcanic activity, especially where this is isolated. |
| Ring of Fire | The Ring of Fire is a major area in the basin of the Pacific Ocean where a large number of earthquakes and volcanic eruptions occur. |
| Subduction zone | Subduction is a geological process that takes place at convergent boundaries of tectonic plates where one plate moves under another and is forced or sinks due to gravity into the mantle. |
| Island arc | An island arc is a type of archipelago, often composed of a chain of volcanoes, with arc-shaped alignment, situated parallel and close to a boundary between two converging tectonic plates. |
| Fissure | a long, narrow opening or line of breakage made by cracking or splitting, especially in rock or earth. |
| Mantle Plume | A mantle plume is an upwelling of abnormally hot rock within the Earth's mantle. As the heads of mantle plumes can partly melt when they reach shallow depths, they are thought to be the cause of volcanic centers. |
| Pluton | a body of intrusive igneous rock. |
| Batholith | A batholith is a large mass of intrusive igneous rock that forms from cooled magma deep in the Earth's crust. Batholiths are almost always made mostly of felsic or intermediate rock types, such as granite, quartz monzonite, or diorite. |
| Dike | a long wall or embankment built to prevent flooding from the sea. |
| Mafic | Mafic is an adjective describing a silicate mineral or igneous rock that is rich in magnesium and iron, and is thus a portmanteau of magnesium and ferric. |
| Felsic | relating to or denoting a group of light-colored minerals including feldspar, feldspathoids, quartz, and muscovite. |
| Viscosity | The viscosity of a fluid is a measure of its resistance to gradual deformation by shear stress or tensile stress. For liquids, it corresponds to the informal concept of "thickness"; for example, honey has a much higher viscosity than water. |
| Quiet Eruption | “quiet” eruptions are known as effusive eruptions. These relatively tame eruptions are characterized by an outpouring of thin, liquid-like lava, as seen with many Hawaiian volcanoes. |
| Pahoehoe Lava | The first and most obvious difference is that pahoehoe flows are smooth down to a scale of a few mm. Instead of consisting of only 1-2 large flow units, a pahoehoe flow consists of thousands on thousands of small flow units called toes. |
| Aa lava | A'a' lava is the most common appearance type of lava flows that cool down forming fragmented, rough, sometimes spiny, or blocky surfaces. |
| Blocky lava | Blocky lava A surface flow of hot, molten lava covered in a carapace of crystalline, angular blocks which tend to be smoothly faceted and may have dimensions up to several metres. The blocks, which have the same composition as the flow interior. |
| Explosive eruption | An explosive eruption is a volcanic term to describe a violent, explosive type of eruption. Mount St. Helens in 1980 is an example. |
| Pyroclastic material | Pyroclastic material is another name for a cloud of ash, lava fragments carried through the air, and vapor. Such a flow is usually *very* hot, and moves *rapidly* due to buoyancy provided by the vapors. |
| Volcanic ash | Volcanic ash consists of fragments of pulverized rock, minerals and volcanic glass, created during volcanic eruptions and measuring less than 2 mm in diameter. |
| Volcanic dust | : fine particles of rock powder that are blown out from a volcano and that may remain suspended in the atmosphere for long periods producing red sunsets and climatic modifications thousands of miles away |
| Lapilli | rock fragments ejected from a volcano. |
| Volcanic bomb | A volcanic bomb is a mass of molten rock (tephra) larger than 64 mm (2.5 inches) in diameter, formed when a volcano ejects viscous fragments of lava during an eruption. They cool into solid fragments before they reach the ground. |
| Volcanic block | A volcanic block is a fragment of rock that measures more than 64 mm (2.5 in) in diameter and is erupted in a solid condition. Blocks are formed from material from previous eruptions. |
| Shield volcano | A shield volcano is a type of volcano usually built almost entirely of fluid lava flows. They are named for their low profile, resembling a warrior's shield lying on the ground. |
| Cinder cone | A cinder cone or scoria cone is a steep conical hill of loose pyroclastic fragments, such as either volcanic clinkers, cinders, volcanic ash, or scoria that has been built around a volcanic vent. |
| Composite volcano | A composite volcano is also known as a stratovolcano. These volcanoes form tall, conical shaped mountains. Most of the Earth's active volcanoes have formed a ring around the Pacific Ocean. |
| Caldera | A caldera is a large cauldron-like depression that forms following the evacuation of a magma chamber/reservoir. When large volumes of magma are erupted over a short time, structural support for the crust above the magma chamber is lost. |
Created by:
ICantRead
Popular Earth Science sets