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Detritus (/ d ə ˈ t r aɪ t ə s /; adj. detrital / d ə ˈ t r aɪ t əl /) is particles of rock derived from pre-existing rock through weathering and erosion. [1] A fragment of detritus is called a clast. [2] Detrital particles can consist of lithic fragments (particles of recognisable rock
The matrix of an igneous rock consists of finer-grained, often microscopic, crystals in which larger crystals, called phenocrysts, are embedded. This porphyritic texture is indicative of multi-stage cooling of magma. For example, porphyritic andesite will have large phenocrysts of plagioclase in a fine-grained matrix.
Chemical weathering of igneous minerals leads to the formation of secondary minerals, which constitute the weathering products of the parent minerals. Secondary weathering minerals of igneous rocks can be classified mainly as iron oxides, salts, and phyllosilicates. The chemistry of the secondary minerals is controlled in part by the chemistry ...
Physical weathering, also called mechanical weathering or disaggregation, is the class of processes that causes the disintegration of rocks without chemical change. Physical weathering involves the breakdown of rocks into smaller fragments through processes such as expansion and contraction, mainly due to temperature changes.
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 ...
A rock in Abisko fractured along existing joints possibly by mechanical frost weathering Columnar jointed basalt in Turkey Columnar jointing in basalt, Marte Vallis, Mars Recent tectonic joint intersects older exfoliation joints in granite gneiss, Lizard Rock, Parra Wirra, South Australia.
Reverse weathering is often found to occur in river deltas as these systems have high sediment accumulation rates and are observed to undergo rapid diagenesis. [13] The formation of silicate clays removes reactive silica from the pore waters of sediment, increasing the concentration of silica found in the rocks that form in these locations. [13]
Glacially abraded rocks in western Norway near Jostedalsbreen gntration. Abrasion is a process of weathering that occurs when material being transported wears away at a surface over time, commonly occurring with ice and glaciers. The primary process of abrasion is physical weathering.