Category: Geography Dictionary

photogrammetry : 1.  The science and technology of obtaining reliable information about physical objects and environments through the process of recording, measuring, and interpreting photographic images (usually aerial or orbital ones) and patterns of electromagnetic radiant imagery and other phenomena.2.  The science of extracting three-dimensional measurements from two-dimensional data, such as images.

permafrost : A permanently frozen layer of soil;^[2] permanently frozen ground at high latitude and high elevation

peninsula : A piece of land surrounded by water along the majority of its border while still being connected to a mainland from which it extends.

parish : A type of subnational division of a country or federal state used for religious, administrative or other purposes.

panhole: Also called a gnamma, weathering pit, and solution pan.

A rounded or circular depression eroded into flat or gently sloping cohesive rock, typically shallow and ranging in diameter from a few centimeters to several meters, that is capable of collecting and holding rainwater and snowmelt. The term is sometimes used interchangeably with pothole, though the latter may also refer to distinct geological features.

panhandle : See salient.

palisade : 1.  A wall of wooden stakes used as a defensive barrier.2.  A line of bold cliffs, especially one showing basaltic columns

oxbow : 1.  A wide U-shaped meander in a river or stream.2.  The lake formed when a meander is cut off from the main stem of the river, creating a separate body of water.

overburden : Material covering a mineral seam or bed that must be removed before the mineral can be removed in strip mining

outwash : Rocky and sandy surface material deposited by melted water that flows from a glacier

outcrop: Also called an outcropping.

Any visible exposure of bedrock or ancient superficial deposits on the surface of the Earth, or more generally, any bare, rocky surface that is topographically distinct from the surrounding terrain. Outcrops occur frequently in places where the rate of erosion exceeds the rate of weathering, such as on steep hillsides and mountains, river banks, and coastlines.

orographic rainfall : Precipitation that results when moist air is lifted over a topographic barrier, such as a mountain range.

ordinal directions : See intercardinal directions.

open range : A cattle- or sheep-ranching area characterized by a general absence of fences and in which livestock are allowed to roam freely

ocean trench : A long, narrow, very deep depression in the ocean floor where, at the junction of two tectonic plates, one plate is subducted steeply beneath the other, often penetrating the mantle.

ocean floor : See seabed.

ocean : The vast, contiguous body of salt water covering more than 70% of the Earth’s surface area and surrounding the continental landmasses, or any portion of this larger body of water that is divided and distinguished from the other portions, each of which is called an ocean, by the presence of the landmasses

oasis : A combination of a human settlement and an area of cultivated vegetation in an otherwise desolate desert or semi-desert environment, made fertile when sources of fresh water, such as underground aquifers, irrigate the surface naturally or via man-made wells.

nubbin : A small, gentle hill consisting of a bedrock core dotted with rounded residual boulders. Nubbins form in a similar way to castle koppies and bornhardts.

Northern Hemisphere : The half sphere of the Earth that is north of the Equator. It is opposite the Southern Hemisphere.

North Magnetic Pole: Also called the Magnetic North Pole or Magnetic North.

The point in the Northern Hemisphere at which the Earth’s magnetic field points vertically downward. It is close to but distinct from the Geographic North Pole and the Geomagnetic North Pole, and its precise location varies considerably over time due to frequent magnetic changes in the Earth’s core. Its counterpart in the Southern Hemisphere is the South Magnetic Pole, though the two poles are not directly opposite each other.

North Geomagnetic Pole : Also called the Geomagnetic North Pole.

The point in the Northern Hemisphere where the axis of a theoretical simplified dipole passing through the center of the Earth would intersect the Earth’s surface. It is antipodal to the South Geomagnetic Pole. Because of the fluid nature of the Earth’s molten core, the true axis of the Earth’s magnetic field is not a perfect dipole, and so the Geomagnetic Poles and the actual Magnetic Poles lie some distance apart.

North Geographic Pole: Also called the Geographic North Pole, Geographic North, or simply the North Pole.

The point in the Northern Hemisphere where the Earth’s axis of rotation meets its surface. It is the northernmost point on Earth, directly opposite the South Geographic Pole, and defines the direction of true north at a latitude of 90 degrees North; its longitude can be assigned any degree value. Unlike the South Pole, the North Pole is not located on a continental landmass but in the middle of the Arctic Ocean. See also North Magnetic Pole.

nodal region : A region characterized by a set of places connected to another place by lines of communication or movement

neighborhood : Often abbreviated to hood.

A geographically localized community within a larger city, town, suburb, or rural area, particularly one which supports considerable face-to-face interactions between residents.

neatline : A line separating the main body of a map from the map’s margin. On a standard quadrangle map, the neatlines are the meridians and parallels delimiting the quadrangle.

navigation :

1.  The determination of position and direction, generally by comparing the navigator’s position to known locations or patterns.

2.  The process of monitoring and controlling the movement of a vehicle or craft from one place to another.

natural landscape : The original landscape that exists before it is acted upon by humans. Contrast cultural landscape.

national park : A type of protected area created and managed as a public park by a national governmental authority for conservation purposes. Though individual governments designate national parks differently, they usually share the common goal of preserving natural or semi-natural landscapes (often wilderness) for posterity and as symbols of national pride.

national mapping agency : A governmental agency which manages, produces, and publishes topographic maps, geographic data, and sometimes cadastral information that is specific to an individual nation or political territory, such as the United Kingdom’s Ordnance Survey.

nation : A stable community of people formed on the basis of a common geographic territory, language, economy, ethnicity, or psychological make-up as manifested in a common culture.

narrows: Also called a narrow.

A land or water passage that is confined or restricted by its narrow breadth, often a strait or a water gap.

muskeg : Another name for a bog, used primarily in Alaska and western Canada.

municipality : A type of general-purpose urban administrative subdivision having corporate status and powers of self-government or jurisdiction as granted by national and/or state laws to which it is subordinate. Municipalities are often included within but usually distinguished from larger administrative divisions such as counties, though the nature of their territorial boundaries and political jurisdictions can vary considerably in different parts of the world.

municipal corporation : The legal term for a government body at the local level, including but not necessarily limited to cities, counties, towns, townships, villages, and boroughs

multilingual : The ability to use more than one language when speaking or writing. This term often refers to the presence of more than two populations of significant size within a single political unit, each group speaking a different language as their primary language

mudflow: Also called a debris flow or lahar.

A flowing mixture of water and debris (intermediate between a volcanic avalanche and a water flood) that forms on the slopes of a volcano.^[

mudflat: Also called a tidal flat.

A type of coastal wetland consisting of exposed layers of bay mud formed by the deposition of silts, clays, and marine animal detritus by tides or rivers. Mudflats usually form within the intertidal zone of relatively sheltered areas such as bays and lagoons.

mouth :

1.  The place where a river or stream flows into another body of water, such as a lake or another river but especially a sea or ocean. Deltas and estuaries occur near the mouths of rivers.

2.  The lower or downstream end or the most accessible entrance of a valley, canyon, ravine, or cave.

mountain range : A series of neighboring mountains or hills, often closely arranged in a line and connected by high ground. Individual mountains within the same mountain range are usually the result of the same orogeny, and often (though not always) share a common form, alignment, and geology.

mountain pass : A navigable route through a mountain range or over a ridge, often crossing a saddle.

mountain : A large landform that rises prominently above the surrounding land in a limited area, usually in the form of a rocky peak with great vertical relief; a mountain is generally considered steeper than a hill. Mountains are formed by volcanic or tectonic forces and erode slowly through the actions of rivers, glaciers, and weathering. Most exist within extensive mountain ranges.

mound : Any heaped pile of earth, gravel, sand, rocks, or debris, typically with a rounded top and of topographically higher elevation than its immediate surroundings.

moraine : The rocks and soil carried and deposited by a glacier. An “end moraine,” either a ridge or low hill running perpendicular to the direction of ice movement, forms at the end of a glacier when the ice is melting

moor: Also called moorland.

An upland habitat and ecoregion characterized by low-growing vegetation on acidic soils and generally referring to uncultivated hills but also including low-lying wetlands.

monadnock : See inselberg.

mole : A long, massive, man-made stone or earthen structure used as a pier or breakwater, or as a causeway between places separated by water, but designed to prevent the free movement of water underneath it (unlike a true pier).

mogote : An isolated, rounded, steep-sided hill composed of either limestone, marble, or dolomite and surrounded by nearly flat alluvial plains, especially as found in tropical regions.

metropolitan coalescence : The merging of the urbanized parts of separate metropolitan areas; a megalopolis is a result of this process

metropolitan area: Also called a metro area or commuter belt.

A region consisting of one or more densely populated urban cores (often a metropolis) and its less populous surrounding territories, including satellite cities, towns, and intervening rural areas, all of which are socioeconomically tied to the core as typically measured by commuting patterns. A metropolitan area usually comprises multiple neighborhoods, jurisdictions, and municipalities, with its inhabitants sharing industry, housing, and many other forms of infrastructure.

metropolis : A large city or conurbation which is considered a significant economic, political, or cultural center for a country or geographic region and/or an important hub for regional or international connections and communications.

metropole : The homeland or central territory from which a colonial empire governs, as opposed to its colonies or overseas territories.

metes and bounds : A system of land survey that defines land parcels according to visible natural landscape features and distance. The resultant field pattern is usually very irregular in shape.

metamorphic rock : Rock that has been physically altered by heat and/or pressure

mesa : An isolated, relatively flat-topped natural elevation, usually more extensive than a butte and less extensive than a plateau

meridian : See longitude.

megalopolis : A chain of roughly adjacent metropolitan areas which have merged into a very large and heavily populated urban complex. See conurbation and metropolitan coalescence.

megacity : A very large city, typically with a population of at least 10 million people. Precise definitions vary, but criteria are usually based on total population and/or population density.

Mediterranean climate : Any climate characterized by mild, rainy winters and hot, dry summers, as experienced in the Mediterranean Basin.

MEDC : An acronym for More Economically Developed Country.

meander scar : Also called a meander scarp.

A typically crescent-shaped incision in a bluff or valley wall formed by the remnants of a dry, abandoned meander.

meander : One of a series of regular sinuous curves, bends, loops, turns, or windings in the main channel of a river, stream, or other watercourse. Meanders are produced by the repetitive upstream erosion and downstream deposition of sediments along the banks of a watercourse as the water flows back and forth across the axis of a valley or floodplain.

massif :

1.  Any section of the Earth’s crust which is demarcated by faults or flexures and tends to retain its internal structure while being displaced as a whole.

2.  A single large mountain mass or compact group of connected mountains forming an independent portion of a mountain range.

marsh : A wetland dominated by herbaceous rather than woody plant species and often found at the edges of lakes and streams, where it forms a transition between the aquatic and terrestrial ecosystems.

maritime climate : A climate strongly influenced by an oceanic environment, typically found on islands and the windward shores of continents. It is characterized by small daily and yearly temperature variation and high relative humidity.

map projection : A systematic transformation of the latitudes and longitudes of locations from the surface of a three-dimensional shape, such as a sphere or an ellipsoid, into locations on a two-dimensional plane. Maps of locations on the Earth require map projections to represent features in a convenient format that is easy to view and interpret, though all map projections necessarily distort the true properties of the Earth’s surface to some degree.

map : A picture of a place that is usually drawn to scale on a flat surface

mantle : A zone in the Earth’s interior between the crust and the core that is 2,900 kilometers (1,800 mi) thick. The lithosphere is composed of the topmost 65–70 kilometres (40–43 mi) of the mantle and the crust.

mammilated : Smooth and rounded in appearance, used of various landforms of different sizes from individual rocks to entire landscapes

makhtesh : A deep, closed valley (usually drained by a single wadi) surrounded by steep walls of resistant rock and superficially resembling a crater. The term is used primarily in the deserts of Israel and Egypt.

mainland : A term used to denote a contiguous landmass or political territory relative to its politically associated but geographically remote outlying territories. It is variously used to refer to the continental (i.e. non-insular) part of a polity relative to its exclaves or oceanic islands; or to the largest or most politically, economically, and/or demographically significant island within an island nation. For example, continental Europe is often considered “the mainland” relative to the British Isles, while the island of Great Britain is considered “the mainland” relative to Northern Ireland and the many smaller islands that constitute the United Kingdom.

main stem: Also called a trunk.

The primary downstream channel of a river as contrasted with its tributaries. Virtually all of the water in a river’s drainage basin eventually flows through the main stem.

magnetic north : The direction a compass points, towards the Magnetic North Pole. Magnetic north differs from true north and grid north.

magma : Molten rock containing liquids, crystals, and dissolved gases that forms within the upper part of the Earth’s mantle and crust. When erupted onto the Earth’s surface, it is called lava.

machair : A fertile, low-lying, grassy plain on the northwest coasts of Ireland and Scotland.

maar : A broad, shallow, flat-bottomed volcanic crater created by an eruption involving groundwater coming into contact with magma. Maars commonly have low rims and subtle relief and characteristically fill with water to form crater lakes.

lowland : Any area of land that is lower in elevation relative to another area. The term is often used as a conditional descriptor to distinguish related habitats or ecosystems, especially freshwater riparian areas, on the basis of elevation above sea level. Lowland areas are usually relatively flat and characterized by slow-flowing waterways and alluvial plains. Contrast upland.

longitude : A measure of distance east or west of the Prime Meridian, a line drawn between the North and South Poles and passing through the Royal Observatory at Greenwich, England.^[2] Lines of longitude, also called meridians, are the imaginary lines that cross the surface of the Earth in a north-south direction (parallel to the Prime Meridian) and measure how far east or west of the Prime Meridian a place is located.

loess : A soil made up of small particles that were transported by the wind to their present location

location theory : A group of theories which seek to explain the siting of economic activities in particular locations.

location : A particular point or place in physical space. Compare absolute location.

loam : A type of easily worked, highly fertile soil composed of clay, silt, and sand in an approximate ratio of 20:40:40. Loams generally heat rapidly, are well-aerated, and drain neither too quickly nor too slowly

lithospheric plates: Also called tectonic plates.

A series of rigid slabs (16 major ones at present) that make up the Earth’s outer shell. These plates float on top of a softer, more plastic layer in the Earth’s mantle

lithosphere : The Earth’s hard, outermost shell. It comprises the crust and the upper part of the mantle. It is divided into a mosaic of 16 major slabs or plates, which are known as lithospheric plates or tectonic plates

levee: Also called a dike, embankment, floodbank, or stopbank.

An elongated naturally occurring ridge or an artificially constructed wall or barrier which regulates water levels in areas prone to flooding. It is usually earthen and often parallel to the course of a river or a coastline.

LEDC : An acronym for Less Economically Developed Country.

legend : A key for understanding the meanings of the symbols or pictures on a map

leeward : Toward the lee side; sheltered from the wind; the direction downwind from a point of reference. Contrast windward.

lee : The side or slope of a physical feature (such as a hill or mountain) which faces downwind, i.e. away from the direction in which the wind is blowing, or which faces away from an advancing glacier or ice sheet. The lee side is often sheltered by the topography from exposure to the wind and any moisture it brings.

leaching : A process of soil nutrient removal through the erosive movement and chemical action of water.

lava : The term used for magma once it has erupted onto the Earth’s surface

latitude : A measure of distance north or south of the Equator. One degree of latitude equals approximately 110 kilometers (68 mi).^[2] Lines of latitude, also called circles of latitude or parallels, are the imaginary lines that cross the surface of the Earth in an east-west direction (parallel to the Equator) and measure how far north or south of the Equator a place is located.

lateral blast : A sideways-directed explosion from the side or summit of a volcano

landscape : 1.  A broad or distinct area of land consisting of a collection of landforms which define a general geomorphologic form or setting, e.g. a mountain range, valley, plain, coast, etc. Landforms within a landscape are spatially associated but may vary in formation processes and age.^[4]2.  The visible features of an area of land, its landforms, and how they integrate with natural or man-made features. In the broadest sense, landscapes may include geophysical landforms such as hills and mountains; bodies of water such as rivers, lakes, and the sea; living elements of land cover such as vegetation; human elements such as buildings, structures, and various forms of land use; and transitory elements such as lighting and weather conditions. They reflect both physical origins and the cultural overlay of human presence in a living synthesis of people and place.

landmass : Any large contiguous area of land typically surrounded by an ocean or sea. Compare continent.

landmark : Any natural or artificial feature that is recognizable enough to be used for navigation; a feature that stands out enough from its environment to be visible across long distances.

landform : A natural feature of the solid surface of the Earth. A combined set of landforms makes up the terrain of a given area, and their arrangement in a landscape is known as topography.

land cover : The physical material present on the surface of the Earth, including categories such as vegetation (grasslands, shrubs, forests, etc.), bare ground, water, asphalt and artificial surfaces, and many others.

land bridge : Any piece of land connecting larger land areas that are otherwise separated by water, especially one over which living organisms, such as terrestrial animals and plants, are able to cross and thereby colonize previously inaccessible lands. Land bridges may be created by falling sea levels, tectonic activity, or post-glacial rebound. Compare isthmus.

lake : A body of water localized in a basin and surrounded entirely by land. Lakes are often defined as separate from any river or stream that serves to feed or drain them.