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Landforms together make up a given terrain, and their arrangement in the landscape is known as topography. Landforms include hills , mountains , canyons , and valleys , as well as shoreline features such as bays , peninsulas , and seas , [ 3 ] including submerged features such as mid-ocean ridges , volcanoes , and the great oceanic basins .
The word lava comes from Italian and is probably derived from the Latin word labes, which means a fall or slide. [2] [3] An early use of the word in connection with extrusion of magma from below the surface is found in a short account of the 1737 eruption of Vesuvius, written by Francesco Serao, who described "a flow of fiery lava" as an analogy to the flow of water and mud down the flanks of ...
Lava lake – Molten lava contained in a volcanic crater; Lava field, also known as lava plain – Large, mostly flat area of lava flows; Lava spine – Vertical growth of solid volcanic lava; Lava tube – Natural conduit through which lava flows beneath the solid surface; Lavaka – Type of gully, formed via groundwater sapping
Basalt is the most common extrusive igneous rock [9] and forms lava flows, lava sheets and lava plateaus. Some kinds of basalt solidify to form long polygonal columns. The Giant's Causeway in Antrim, Northern Ireland is an example. The molten rock, which typically contains suspended crystals and dissolved gases, is called magma. [10]
Sheet flow lava appears like a wrinkled or folded sheet, while pillow lava is bulbous, and often looks like a pile of pillows atop one another. [3] An important aspect of lava flow morphology is a phenomenon known as lava flow inflation. This occurs in pāhoehoe flows that have a high effusion rate, and initially forms a thin crust atop the ...
In an explosive eruption, large amounts of gas are dissolved in extremely viscous lava; this lava froths to the surface until the material is expelled rapidly due to the trapped pressure. Sometimes in such an event a lava plug or volcanic neck forms from lava that solidifies inside a volcano's vent, causing heat and pressure to build up to an ...
Geomorphology (from Ancient Greek γῆ (gê) ' earth ' μορφή (morphḗ) ' form ' and λόγος ' study ') [2] is the scientific study of the origin and evolution of topographic and bathymetric features generated by physical, chemical or biological processes operating at or near Earth's surface.
Tectonic subsidence is the sinking of the Earth's crust on a large scale, relative to crustal-scale features or the geoid. [1] The movement of crustal plates and accommodation spaces produced by faulting [2] brought about subsidence on a large scale in a variety of environments, including passive margins, aulacogens, fore-arc basins, foreland basins, intercontinental basins and pull-apart basins.