Bowen’s Reaction Series
Different minerals are stable at different pressure and temperature conditions; high-temperature minerals are less stable, and magma becomes richer in silica through magmatic differentiation.
| Term | Definition |
|---|---|
Bowen’s Reaction Series | Different minerals are stable at different pressure and temperature conditions; high-temperature minerals are less stable, and magma becomes richer in silica through magmatic differentiation. |
Weathering | The physical disintegration of rocks and chemical decomposition of their component minerals. |
Soil | The portion of Earth's surface sediment that can sustain life, formed mostly from weathered bedrock. |
Mechanical Weathering | The breakdown of rocks into smaller fragments without changing their chemical composition. |
Chemical Weathering | The decomposition of rocks and minerals through chemical reactions that alter their composition. |
Joints | Regularly spaced cracks in rock outcrops formed by stress such as temperature or pressure changes. |
Columnar Joints | Joints formed by cooling and contraction of igneous rocks such as basalt. |
Exfoliation | A type of jointing where outer rock layers peel away due to pressure release or temperature changes. |
Frost Wedging | Water enters cracks, freezes, expands 9–10%, and forces the rock apart. |
Crystal Wedging | Salt crystals grow in rock cracks and push the rock apart as they expand. |
Thermal Expansion and Contraction | Repeated heating and cooling cause minerals to expand and contract, producing cracks in rock. |
Organic Weathering | Mechanical weathering caused by plant roots, burrowing animals, and microorganisms. |
Dissolution | Chemical weathering process in which minerals dissolve in water, especially acidic rainwater. |
Hydrolysis | Chemical reaction where hydrogen ions in water remove ions from a mineral's structure and form new minerals. |
Oxidation | A chemical reaction in which a substance loses electrons; commonly affects iron-bearing minerals. |
Reduction | A chemical reaction in which a substance gains electrons. |
Redox Reaction | Oxidation and reduction occurring together, with one compound losing electrons and another gaining them. |
Hydration | The absorption of water into a mineral’s crystal structure, causing expansion and weakening of rocks. |
Regolith | Loose rock and mineral fragments produced by weathering. |
Residual Soil | Soil formed directly from the weathering of underlying bedrock. |
Transported Soil | Soil moved from its original location by water, ice, or wind. |
Soil Profile | The layered structure of soil horizons. |
O Horizon | The uppermost soil layer rich in organic matter. |
A Horizon | Layer containing plant roots, microorganisms, and burrowing animals. |
Topsoil | Combination of the O and A horizons; primary zone of leaching. |
B Horizon | Soil layer where materials leached from above accumulate. |
E Horizon | A leached layer that may separate the A and B horizons in older soils. |
C Horizon | A layer consisting mostly of fragmented and weathered bedrock. |
Factors Influencing Soil Development | Bedrock composition, sediment deposition, time, climate, topography, and organic activity. |
Plate Tectonics and Weathering | Plate movements influence weathering, soil formation, topography, volcanism, and global temperatures. |
Effusive Eruption | A relatively gentle volcanic eruption involving low-viscosity, low-gas basaltic magma. |
Explosive Eruption | A violent eruption involving viscous, gas-rich magma that produces pyroclastic material. |
Hawaiian Eruption | Effusive eruption characterized by fluid basaltic lava flows, lava fountains, and little ash. |
Shield Volcano | A broad volcano with gentle slopes formed by repeated low-viscosity lava flows. |
Strombolian Eruption | Mild explosive eruption producing bursts of lava, ash, gas, and volcanic bombs. |
Volcanic Bomb | A large fragment of molten rock ejected during an eruption. |
Lapilli | Small volcanic fragments ejected during eruptions. |
Plinian Eruption | Highly explosive eruption producing towering ash columns, widespread ash fall, and pyroclastic flows. |
Pyroclastic Flow | A fast-moving avalanche of hot ash, gas, and volcanic debris. |
Lahar | A volcanic mudflow composed of water mixed with volcanic ash and debris. |
Caldera | A large depression formed when a volcano collapses after magma is removed from beneath it. |
Pélean Eruption | An explosive eruption involving viscous magma, lava dome collapse, and pyroclastic flows. |
Lava Dome | A steep-sided mound formed by the accumulation of viscous lava. |
Nuée Ardente | A glowing avalanche of hot volcanic ash and gas; a type of pyroclastic flow. |
Yellowstone Caldera | A massive caldera in the United States formed about 630,000 years ago by a supervolcanic eruption. |
Santorini Caldera | A volcanic caldera in Greece formed by the Minoan eruption around 1600 BCE. |
Calcium Carbonate (CaCO3) | The main component of limestone, occurring as calcite or aragonite. |
Carbonic Acid (H2CO3) | A weak acid formed when water combines with carbon dioxide. |
Limestone Weathering | The dissolution of limestone when carbonic acid reacts with calcium carbonate. |
Calcium Bicarbonate [Ca(HCO3)2] | A water-soluble product formed when carbonic acid dissolves limestone. |
Precipitation of Calcium Carbonate | The process by which dissolved calcium bicarbonate breaks down, depositing solid calcium carbonate. |