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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 ...
The two main types of lava field structures are defined as sheet flow lava and pillow lava. 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. [2] An important aspect of lava flow morphology is a phenomenon known as lava flow inflation. This occurs in ...
The geology of malpaís terrain is bare to thin layers of soil over lava with sparse vegetation. The lava fields usually consist of lava tube systems, sinkholes, pyroclastic deposits from cinder cone volcanoes, and ʻaʻā and pāhoehoe lava flows. The lava tubes can vary from intact caves to partial or completely collapsed passages.
An ice-marginal lava flow is a lava flow that comes into direct contact with a glacier or the margins of a large ice sheet. As the lava reaches the margins of an ice sheet, the front of the lava flow cools very quickly to form a barrier. Behind this barrier, the lava begins to pool, ceasing the contact between the hot lava and cold ice.
The diameter of these prismatic columns ranges from a few centimeters to several metres. They are often oriented perpendicular to either the upper surface and base of lava flows and the contact of the tabular igneous bodies with the surrounding rock. This type of jointing is typical of thick lava flows and shallow dikes and sills. [5]
Extrusive rock refers to the mode of igneous volcanic rock formation in which hot magma from inside the Earth flows out (extrudes) onto the surface as lava or explodes violently into the atmosphere to fall back as pyroclastics or tuff. [1] In contrast, intrusive rock refers to rocks formed by magma which cools below the surface. [2]
Fish Lake is an ephemeral lake that dries up during the summer season, formed by the damming of local water drainages by a lava flow from Sand Mountain Volcanic Field about 3,850 years ago. [11] Local topography has influenced eruptive activity in the past, directing lava flows downhill to the west and, with wind, directing tephra to the ...
In volcanology, a pressure ridge or a tumulus (plural: tumuli), and rarely referred to as a schollendome, is sometimes created in an active lava flow. [1] Formation occurs when the outer edges and surfaces of the lava flow begin to harden. [1] If the advancing lava underneath becomes restricted it may push up on the hardened crust, tilting it ...