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Trachyandesite is an extrusive igneous rock with a composition between trachyte and andesite. It has little or no free quartz , but is dominated by sodic plagioclase and alkali feldspar . It is formed from the cooling of lava enriched in alkali metals and with an intermediate content of silica .
Trachyte (/ ˈ t r eɪ k aɪ t, ˈ t r æ k-/) is an extrusive igneous rock composed mostly of alkali feldspar. It is usually light-colored and aphanitic (fine-grained), with minor amounts of mafic minerals, [ 1 ] and is formed by the rapid cooling of lava (or shallow intrusions) enriched with silica and alkali metals .
In histology (microscopic anatomy), the lobules of liver, or hepatic lobules, are small divisions of the liver defined at the microscopic scale. The hepatic lobule is a building block of the liver tissue , consisting of a portal triad, hepatocytes arranged in linear cords between a capillary network, and a central vein .
A liver segment is one of eight segments of the liver as described in the widely used Couinaud classification (named after Claude Couinaud) in the anatomy of the liver.This system divides the lobes of the liver into eight segments based on a transverse plane through the bifurcation of the main portal vein, [1] arranged in a clockwise manner starting from the caudate lobe.
The falciform ligament, visible on the front of the liver, makes a superficial division of the right and left lobes of the liver. From the underside, the two additional lobes are located on the right lobe. [2] A line can be imagined running from the left of the vena cava and all the way forward to divide the liver and gallbladder into two ...
Thin sections are prepared in order to investigate the optical properties of the minerals in the rock. This work is a part of petrology and helps to reveal the origin and evolution of the parent rock. A photograph of a rock in thin section is often referred to as a photomicrograph.
Phonolite is a variation of the igneous rock trachyte that contains nepheline or leucite rather than quartz. [1] It has an unusually high (12% or more) Na 2 O + K 2 O content, defining its position in the TAS classification of igneous rocks. Its coarse grained (phaneritic) intrusive equivalent is nepheline syenite. Phonolite is typically fine ...
"Imperial Porphyry" from the Red Sea Mountains of Egypt A waterworn cobble of porphyry Rhyolite porphyry from Colorado; scale bar in lower left is 1 cm (0.39 in). Porphyry (/ ˈ p ɔːr f ə r i / POR-fə-ree) is any of various granites or igneous rocks with coarse-grained crystals such as feldspar or quartz dispersed in a fine-grained silicate-rich, generally aphanitic matrix or groundmass.