Glossary

Feldspar

Feldspar is an aluminum silicate used in ceramics, glass, and construction.

^VVog

Vog, short for volcanic smog, is a form of air pollution caused by the release of sulfur dioxide and other volcanic gases into the atmosphere, where they react with oxygen, moisture, and sunlight to form fine particles. Vog is significant in environmental science for its impact on air quality, human health, and the environment in areas downwind of active volcanoes.

Reference: Tam, E., et al. (2016). “Volcanic Air Pollution over the Island of Hawai’i: Emission Sources, Impacts, and Mitigation.” Atmospheric Environment, 142, 16-29.

^VVolatile Content

Volatile content refers to the amount of volatile compounds, such as water, carbon dioxide, and sulfur dioxide, present in a magma. The volatile content is significant in volcanology for understanding the explosivity of volcanic eruptions, the formation of different volcanic rocks, and the degassing processes during magma ascent.

Reference: Wallace, P. J., & Edmonds, M. (2011). “The Sulfur Budget in Magmas: Evidence from Melt Inclusions, Submarine Glasses, and Volcanic Gas Emissions.” Reviews in Mineralogy and Geochemistry, 73(1), 215-246.

^VVolcanic Arc

A volcanic arc is a chain of volcanoes formed above a subducting tectonic plate, typically parallel to an oceanic trench. Volcanic arcs are significant in understanding subduction zone dynamics, magma generation, and the formation of island and continental arcs.

Reference: Stern, R. J. (2002). “Subduction Zones.” Reviews of Geophysics, 40(4), 3-1-3-38.

^VVolcanic Ash

Volcanic ash consists of fine particles of pulverized rock and glass created during explosive volcanic eruptions. It is significant in volcanology for understanding eruption dynamics, the dispersal of ash in the atmosphere, and its impact on climate, aviation, and human health.

Reference: Fisher, R. V., & Schmincke, H.-U. (1984). “Pyroclastic Rocks.” Springer.

^VVolcanic Bomb

A volcanic bomb is a large fragment of molten rock ejected during a volcanic eruption that solidifies before reaching the ground. Volcanic bombs are significant in volcanology for understanding the mechanisms of explosive eruptions, the size and distribution of pyroclastic material, and the hazards posed to areas near active volcanoes.

Reference: Fisher, R. V., & Schmincke, H.-U. (1984). “Pyroclastic Rocks.” Springer.

^VVolcanic Chain

A volcanic chain is a linear arrangement of volcanoes, often formed along tectonic plate boundaries, such as island arcs or continental volcanic arcs. These chains are significant in understanding the processes of subduction, magma generation, and the spatial distribution of volcanic activity.

Reference: Tatsumi, Y., & Eggins, S. (1995). “Subduction Zone Magmatism.” Blackwell Science.

^VVolcanic Collapse

Volcanic collapse refers to the structural failure of a volcano’s edifice, often resulting in a landslide or the formation of a caldera. This process is significant in volcanology for understanding the stability of volcanic structures, the triggers of volcanic landslides, and the hazards posed by such collapses.

Reference: Siebert, L. (1984). “Large Volcanic Debris Avalanches: Characteristics of Source Areas, Deposits, and Associated Eruptions.” Journal of Volcanology and Geothermal Research, 22(3-4), 163-197.

^VVolcanic Crater

A volcanic crater is a bowl-shaped depression at the summit or on the flanks of a volcano, formed by explosive eruptions or the collapse of the summit. Volcanic craters are significant in volcanology for understanding eruption dynamics, crater formation processes, and the hazards associated with volcanic eruptions.

Reference: Harris, S. L. (2005). “Fire Mountains of the West: The Cascade and Mono Lake Volcanoes.” Mountain Press Publishing Company.

^VVolcanic Dome

A volcanic dome is a mound-shaped protrusion resulting from the slow extrusion of highly viscous lava, typically rhyolite or dacite. Volcanic domes are significant in volcanology for understanding the dynamics of volcanic eruptions, the formation of lava domes, and the potential hazards associated with dome collapse and pyroclastic flows.

Reference: Fink, J. H., & Anderson, S. W. (2000). “Lava Domes and Coulees.” Encyclopedia of Volcanoes, 307-319.

^VVolcanic Gases

Volcanic gases are the volatile components released from magma during an eruption, including water vapor, carbon dioxide, sulfur dioxide, hydrogen sulfide, and other trace gases. These gases are significant in volcanology for understanding eruption dynamics, the impact of volcanic eruptions on the atmosphere, and the monitoring of volcanic activity.

Reference: Symonds, R. B., Gerlach, T. M., & Reed, M. H. (2001). “Magmatic Gas Scrubbing: Implications for Volcano Monitoring.” Journal of Volcanology and Geothermal Research, 108(1-4), 1-4.

^VVolcanic Glass

Volcanic glass is a natural glass formed by the rapid cooling of molten lava, preventing the formation of crystals. Obsidian is a common example. Volcanic glass is significant in petrology and archaeology for understanding the cooling history of volcanic eruptions, the composition of magmas, and the use of volcanic glass in prehistoric tools.

Reference: Dingwell, D. B. (1996). “Volcanic Glasses.” Reviews in Mineralogy and Geochemistry, 32(1), 69-106.

^VVolcanic Pipe

A volcanic pipe is a vertical conduit through which magma travels from a magma chamber to the surface during a volcanic eruption. Volcanic pipes are significant in geology for understanding the transport of magma, the formation of volcanic features like diatremes, and the emplacement of kimberlite pipes that may host diamonds.

Reference: Mitchell, R. H. (1986). “Kimberlites: Mineralogy, Geochemistry, and Petrology.” Plenum Press.

^VVolcanic Plateau

A volcanic plateau is a large, flat elevated area formed by extensive volcanic activity, typically through the accumulation of successive lava flows. These plateaus are significant in volcanology for understanding the processes of flood basalt eruptions, the formation of large igneous provinces, and the role of volcanic activity in shaping the Earth’s surface.

Reference: Cox, K. G. (1980). “Flood Basalts, Subduction, and the Breakup of Gondwanaland.” Nature, 283(5748), 252-255.

^VVolcanic Plume

A volcanic plume is a column of volcanic gases, ash, and aerosols emitted during an eruption, rising into the atmosphere and often spreading over large areas. Volcanic plumes are significant in volcanology and atmospheric science for their impact on air travel, climate, and the distribution of volcanic ash.

Reference: Sparks, R. S. J., & Carey, S. N. (1991). “Pyroclastic Flows and Explosive Volcanism.” Geological Society of London Special Publication, 145(1), 1-8.

^VVolcanic Rift

A volcanic rift is a linear zone where the Earth’s crust is being pulled apart, allowing magma to rise and create new crust, typically found at divergent plate boundaries or within volcanic hotspots. Volcanic rifts are significant in understanding the processes of crustal extension, the formation of rift volcanoes, and the dynamics of magma movement.

Reference: Buck, W. R. (2004). “Consequences of Asthenospheric Variability on Continental Rifting.” Geological Society of London Special Publication, 222(1), 43-54.

^VVolcano

A volcano is a geological feature formed by the eruption of magma onto the Earth’s surface, creating a mountain or hill with a vent through which lava, ash, and gases are expelled. Volcanoes are significant in geology for understanding the processes of magma generation, the dynamics of eruptions, and the formation of volcanic landforms.

Reference: Francis, P., & Oppenheimer, C. (2004). “Volcanoes.” Oxford University Press.

^WWadati-Benioff Zone

The Wadati-Benioff zone is a planar zone of seismicity corresponding to the subducting slab of a convergent boundary, extending from shallow depths near the trench to deep within the mantle. This zone is significant in seismology and plate tectonics for understanding the processes of subduction, earthquake generation, and the structure of subducting plates.

Reference: Frohlich, C. (2006). “Deep Earthquakes.” Cambridge University Press.

^WWadi

A wadi is a dry riverbed or valley in a desert region that only carries water during periods of heavy rain. Wadis are significant in arid region geomorphology for understanding episodic streamflow, sediment transport, and the development of desert landscapes.

Reference: “Torrent valley”. Insight on the Scriptures. Vol. 2: Jehova – Zuzim and Index. Watch Tower Bible and Tract Society of New York. 1988. p. 1115. The term “wadi” (Arabic) is also used to designate a torrent valley … whereas others are torrents during the rainy season but dry up completely during the rainless season.

^WWash Load

Wash load refers to the fine sediment particles, such as silt and clay, that are transported in suspension by a river and do not come into frequent contact with the riverbed. Wash load is significant in fluvial geomorphology for understanding sediment transport dynamics, riverine sediment budgets, and the formation of floodplains and deltas.

Reference: Leopold, L. B., Wolman, M. G., & Miller, J. P. (1964). “Fluvial Processes in Geomorphology.” Dover Publications.

^WWater Budget

A water budget is a balance sheet of water inflows, outflows, and storage changes within a specific system, such as a watershed, aquifer, or lake. The water budget is significant in hydrology and water resource management for understanding the availability of water resources, managing water supply, and assessing the impacts of land use and climate change on water systems.

Reference: Viessman, W., & Lewis, G. L. (2003). “Introduction to Hydrology.” Prentice Hall.

^WWater Column

The water column is a conceptual column of water from the surface to the bottom of a body of water, used to study the distribution of physical, chemical, and biological properties at different depths. The water column is significant in oceanography and limnology for understanding oceanic and freshwater processes, the behavior of nutrients and pollutants, and the distribution of marine and freshwater organisms.

Reference: Stewart, R. H. (2008). “Introduction to Physical Oceanography.” Texas A&M University.

^WWater Gap

A water gap is a pass or gorge through which a river flows, cutting across a mountain ridge or other resistant rock formation. Water gaps are significant in geomorphology for understanding the history of river incision, the evolution of drainage systems, and the tectonic activity in a region.

Reference: Oberlander, T. M. (1965). “The Zagros Streams: A New Interpretation of Transverse Drainage in an Orogenic Zone.” Syracuse Geographical Series, No. 1.

^WWave Base

Wave-base is the depth in the ocean below which the effects of surface waves on sediment movement become negligible. It is significant in marine geology and sedimentology for understanding sediment deposition, the formation of marine sedimentary structures, and the impact of wave energy on the seabed.

Reference: Davis, R. A. (1985). “Coastal Sedimentary Environments.” Springer.

^MArchives: Glossary

Mudstone is a fine-grained sedimentary rock composed primarily of clay and silt-sized particles. It is often formed in low-energy environments such as deep marine basins, lakes, and floodplains. Mudstone is significant in understanding depositional environments, the preservation of fossils, and the geochemical cycles of elements.

Reference: Potter, P. E., Maynard, J. B., & Depetris, P. J. (2005). “Mud and Mudstones: Introduction and Overview.” Springer.