[...]... [GEOL] That portion of the A horizon of a soil profile which is composed of pure humus { ¦a¦o hə rızиən } ¯ ¯ ¯ Aoo horizon [GEOL] Uppermost portion of the A horizon of a soil profile which consists of undecomposed vegetable litter { ¦a¦o¦o hə rızиən } ¯ ¯ ¯ ¯ apex [GEOL] The part of a mineral vein nearest the surface of the earth { a peks } ¯ aphotic zone [OCEANOGR] The deeper part of the ocean where... mamиəlz } ¯ Age of Man [GEOL] An informal designation of the Quaternary period of geologic time { aj əv man } ¯ age of parallax inequality [GEOPHYS] The time interval between the perigee of the moon and the maximum effect of the parallax (distance of the moon) upon the range of tide or speed of tidal current Also known as parallax age { aj əv parи ¯ ə laks inиe kwalиədиe } ¨ ¯ ¯ age of phase inequality... or speed of the tidal current occurs Also known as age of diurnal tide; diurnal age { aj əv dı ərnиəl inиe kwalиədиe } ¨ ¯ ¯ ¯ ¯ age of diurnal tide See age of diurnal inequality { aj əv dı ərnиəl tıd } ¯ ¯ ¯ Age of Fishes [GEOL] An informal designation of the Silurian and Devonian periods of geologic time { aj əv fishиəz } ¯ Age of Mammals [GEOL] An informal designation of the Cenozoic era of geologic... kilometers) of any runway of the airport { er kraft selиiŋ } ¯ aircraft electrification [METEOROL] 1 The accumulation of a net electric charge on the surface of an aircraft 2 The separation of electric charge into two concentrations of opposite sign on distinct portions of an aircraft surface { er kraft i lekиtrəи fə kaиshən } ¯ aircraft icing [METEOROL] The accumulation of ice on the exposed surfaces of aircraft... introduction of the mineral adularia { ə julи əиrə zaиshən } ¯ advance [GEOL] 1 A continuing movement of a shoreline toward the sea 2 A net movement over a specified period of time of a shoreline toward the sea [HYD] The forward movement of a glacier { əd vans } advection [METEOROL] The process of transport of an atmospheric property solely by the mass motion of the atmosphere [OCEANOGR] The process of transport... position of the poles at the time of firing This allows for dating, for example, of when a fire pit was used, based on the reconstruction of pole position for earlier times { ¦arиkeиo mag¦nedиik daиdiŋ } ¨ ¯ ¯ ¯ Archeozoic [GEOL] 1 The era during which, or during the latter part of which, the oldest system of rocks was made 2 The last of three subdivisions of Archean time, when the lowest forms of life... the new or full moon and the maximum effect of these phases upon the range of tide or speed of tidal current Also known as age of tide; phase age { aj əv faz inиe kwalи ədиe } ¨ ¯ ¯ ¯ ¯ age of tide See age of phase inequality { aj əv tıd } ¯ ¯ ageostrophic wind See geostrophic departure { ə jeиə¦strafиik wind } ¨ ¯ age ratio [GEOL] The ratio of the amount of daughter to parent isotope in a mineral being... down the flanks of a volcano or along the surface of the ground Also known as glowing avalanche; incandescent tuff flow 2 A deposit of volcanic ash and other debris resulting from such a flow and lying on the surface of the ground { ash flo } ¯ ash fusibility [GEOL] The gradual softening and melting of coal ash that takes place with increase in temperature as a result of the melting of the constituents... theory and practice of synoptic surfacechart analysis by the so-called Norwegian methods, which involve the concepts of the polar front and of the broad-scale air masses which it separates { er mas ə nalиəиsəs } air-mass climatology [CLIMATOL] The representation of the climate of a region by the frequency and characteristics of the air masses under which it lies; basically, a type of synoptic climatology... alluvial [GEOL] 1 Of a placer, or its associated valuable mineral, formed by the action of running water 2 Pertaining to or consisting of alluvium, or deposited by running ¨ ¯ water { ə luvиeиəl } alluvial cone [GEOL] An alluvial fan with steep slopes formed of loose material washed down the slopes of mountains by ephemeral streams and deposited as a conical mass of low slope at the mouth of a gorge Also . useful listings of data from the varioius disclriplines of earth science. It is the editors’ hope that the Second Edition of the McGraw-Hill Dictionary of Earth. Click Here for Terms of Use. How to Use the Dictionary ALPHABETIZATION. The terms in the McGraw-Hill Dictionary of Earth Science, Second Edition, are alphabetized