This page lists the latest 50 glossary entries. The fifth edition of the Glossary of Geology contains nearly 40,000 entries, including 3.600 new terms and nearly 13,000 entries with revised definitions from the previous edition. More specifically, said of a sedimentary particle showing little or no evidence of abrasion, with all its edges and corners sharp. It is the fundamental lithostratigraphic unit. Any of several hard, inert materials, such as sand, gravel, slag, or crushed stone, used for mixing with a cemeting or bituminous material to form concrete, mortar, or plater; or used alone, as in railroad ballast or graded fill. This page lists the latest 50 glossary entries. Sandstone -- A clastic sedimentary rock composed of grains of sand size set in a matrix of silt or clay and more or less firmly united by a cementing material (commonly silica, iron oxide, or calcium carbonate); the consolidated equivalent of sand. Most asteroid orbits are between those of planets Mars and Jupiter. 2 0 obj x��\Ys�F�~W��CE�K�FD��p8B�$��Wk���U@'�L��Ife]y|yT_������(~�����X����t}���u}�mW_�>o��m�����S]m���?��on����/��I!e�����)b��J�Q��"������X|�n_��������yy�.j�&�R/��_��/_����:�6SQ�}��~�������k��(���Ѵm.#Y���,�Eu����YJ��`�BܵK���?/s�B��m�`�Mc�_���|�?�BE�JE�j�.3B��p#���~�����ߵ�1�r7w�x�ye3W��2J Geology Glossary and Terms. The Glossary of Geology (AGI, 1997) serves as a major source for many glossary terms. You can search for an entry using this form: Toolbox for Research and Exploration (TREX). Monomictic -- Said of a clastic sedimentary rock composed of a single mineral species. Native iron is rare in terrestrial rocks but common in meteorites. PSI, a Nonprofit Corporation 501(c)(3), and an Equal Opportunity/M/F/Vet/Disabled/Affirmative Action Employer.Corporate Headquarters: 1700 East Fort Lowell, Suite 106 * Tucson, AZ 85719-2395 * 520-622-6300 * FAX: 520-622-8060Copyright © 2021 . This type of crater has an uplift that forms in the center due to the earth rebounding from the impact event. 3. Glossary of Geological Terms - Free download as PDF File (.pdf), Text File (.txt) or read online for free. Pitchstone -- A volcanic glass with a waxy dull resinous luster. Said of an ore deposit formed adjacent to a volcanic feature to which it is genetically related and from which its constituents have been derived. From The Gemology Project. Here is a glossary of Geological terms. See also the rock and soil classification table and the periodic table of elements. Abrasion:. A common vocabulary with clear definitions promotes effective communication. Glossary of Terms. An informal term applied by drillers to a sedimentary rock with certain drilling characteristics, e.g. Geology is the study of the Earth, the materials of which it is made, the structure of those materials, and the processes acting upon them. The definitions are largely based on input from: • ISRM Terminology (1975) • Handbook in Engineering geology and rock mechanics, issued by the Norwegian Rock Mechanics Group (NBG), (2000); A body of rock strata that consists dominantly of a certain lithologic type or combination of types. This indispensable reference tool contains nearly 40,000 entries, including 3,600 new terms and nearly 13,000 entries with revised *  Most of the terms in this list from the Dictionary of Geological Terms, 3rd Ed., R.L. This term is generally used for any hot water, but has been restricted by some to water of magmatic origin. It closely resembles a tuff breccia or pumiceous tuff but is of non-volcanic orgin and can be distinguished by the presence of shock-metamorphic effects. Bedrock -- The solid rock that underlies gravel, soil, or other surficial material. "Bombs" - volcanic: lumps of rock and/or lava thrown out of a volcano during an eruption. Geology - the study of the earth. 3. More generally, solid fragmental material transported and deposited by wind, water, or ice, chemically precipitated from solution, or secreted by organisms, and that forms in layers in loose unconsolidated form such as sand, mud, or till. Sometimes spelled cañon. Gypsum -- A widely distributed mineral consisting of hydrous calcium sulfate: CaSO 4- H 2 O. Canyon -- A stream-cut chasm or gorge, the sides of which are composed of cliffs or a series of cliffs rising from its bed. Most glasses are supercooled liquids, i.e., metastable, but there is no break in the change in properties between the metastable and stable states. The term is often applied generically to all acidic precipitation. Acidification: Process whereby soil becomes acid (pH < 7) because acid parent material is present or in regions with high rainfall, where soil leaching occurs. A topographic feature differing conspicously from adjacent features, e.g. in clays) in distinct, transparent monoclinic crystals or in large crystalline masses that easily cleave into broad folia. Glossary of geology terms: | This page is a |glossary of geology|. Aggregate -- A mass or body of rock particles, mineral grains, or both. Jump to: navigation, search. It yields lime on calcination. Clast -- An individual constituent, grain, or fragment of a detrital sediment or sedimentary rock, produced by the physical disintegration of a larger rock mass. Canyons are characteristic of arid or semiarid regions where downcutting by streams greatly exceeds weathering. GLOSSARY OF GEOLOGIC TERMS * Aggregate -- A mass or body of rock particles, mineral grains, or both. It is a very dense polymorphic form of quartz that is stable at room temperatures only at pressures above 20,000 bars. Deformation -- A general term for the processes of folding, faulting, shearing, compression, or extension of rocks as a result of various earth forces. Clays may be classified by use, origin, mineral composition, or color. Biology refers to the science of living organisms. Any of several hard, inert materials, such as sand, gravel, slag, or crushed stone, used for mixing with a cemeting or bituminous material to form concrete, mortar, or plater; or used alone, as in railroad ballast or graded fill. Geology is the scientific study of the Earth, the materials of which it is made, the structure of those materials, and the processes acting upon them. It may be red, brown, black, or gray. Common impurities include chert and clay. Ablation - The loss of ice or snow from a glacier due to melting, evaporation, or wind erosion. This indispensable reference tool contains nearly 40,000 entries of terms used in the earth and environmental science literature. Soil Science Division staff and NCSS participants are encouraged to propose additions and changes to the glossary for use in pedon descriptions, soil map unit descriptions, and soil survey publications. The sand particles usually consist of quartz, and the term "sandstone" when used without qualification, indicates a rock containing about 85-90% quartz. Glacier -- A large mass of ice formed on land by the compaction and recrystallization of snow, creeping downslope or outward due to the stress of its own weight, and surviving from year to year. Cement -- Chemically precipitated mineral material that occurs in the spaces of a sedimentary rock, thus binding the grains into a rigid mass. Obsidian -- A back or dark-colored volcanic glass, usually of rhyolitic composition, characterized by conchoidal fracture. Simple Crater -- An impact crater with a smooth bowl shape and a small depth to diameter ratio, typically near 1:6. -Glossary of geology -Chronostratigraphy -Chronozone -Deep hot zone -Dip-slip fault -Discrete debris accumulation -Eonothem -Erathem -Friability -Stratigraphic unit -Geon (geology) -Glossary of meteoritics -Joint (geology) -Leaverite -Oblique-slip fault -Paralithic -Primary rock … Mineral -- A naturally occurring inorganic elementy or compound having an orderly internal structure and characteristic chemical composition, crystal form, and physical properties. Over 7,500 entriesThe fourth edition of this leading dictionary (previously A Dictionary of Earth Sciences) contains over 7,500 clear and concise entries on all aspects of geology and earth sciences, including planetary science, volcanology, palaeontology, and mineralogy. As collections management throughout the USGS expands, this list of terms will grow and definitions may change. 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