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This glossary of geography terms is a list of definitions of terms and concepts used in geography and related fields, including Earth science, oceanography, cartography, and human geography, as well as those describing spatial dimension, topographical features, natural resources, and the collection, analysis, and visualization of geographic ...
About 311 million years ago, in the Late Carboniferous, the order Spongillida split from the marine sponges, and is the only sponges to live in freshwater environments. [8] Some species are brightly colored, with great variety in body shape; the largest species are over 1 m (3.3 ft) across. [6] They reproduce both sexually and asexually.
Bioerosion describes the breakdown of hard ocean substrates – and less often terrestrial substrates – by living organisms. Marine bioerosion can be caused by mollusks, polychaete worms, phoronids, sponges, crustaceans, echinoids, and fish; it can occur on coastlines, on coral reefs, and on ships; its mechanisms include biotic boring, drilling, rasping, and scraping.
Weathering is the chemical and physical disruption of earth materials in place on exposure to atmospheric or near surface agents, and is typically studied by soil scientists and environmental chemists, but is an essential component of geomorphology because it is what provides the material that can be moved in the first place.
The aromatization of an additional ring in 4,12-Dihydrogen-4,8,12-triazatriangulene is utilized by Al-Yassiri and Puchta to get a representative for a new class of Δ-shaped proton sponges. [8] This compound has a calculated proton affinity of 254 kcal/mol (B3LYP/6-311+G**) and is therefore between 1,8-Bis(dimethylamino)naphthalene and HMPN.
Sorbents collect specific liquids or gases depending on the composition of the material being used in the sorbent. Some of the most common sorbents used to clean oil spills are made from materials that are both oleophilic and hydrophobic, have high surface area through structural designs that include pores and capillaries, and draw in liquid through capillary action. [1]
A 1.5 km stretch of reef-forming stromatolites (primarily of the genus Scytonema) occurs in Chetumal Bay in Belize, just south of the mouth of the Rio Hondo and the Mexican border. [47] Large microbialite towers up to 40 m high were discovered in the largest soda lake on Earth Lake Van in eastern Turkey.
Chert (/ tʃ ɜːr t /) is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, [1] the mineral form of silicon dioxide (SiO 2). [2] Chert is characteristically of biological origin, but may also occur inorganically as a chemical precipitate or a diagenetic replacement, as in petrified wood.