—stratigrapher, stratigraphist, n. —stratigraphic /strat'i graf"ik/, stratigraphical, adj. —stratigraphically, adv./streuh tig"reuh fee/, n.a branch of geology dealing with the classification, nomenclature, correlation, and interpretation of stratified rocks.[1860-65; STRATI- + -GRAPHY]
* * *Scientific discipline concerned with describing rock successions and interpreting them in terms of a general time scale.It provides a basis for historical geology, and its principles and methods are applied in such fields as petroleum geology and archaeology. Stratigraphic studies deal primarily with sedimentary rocks but may also encompass layered igneous rocks (e.g., those resulting from successive lava flows) or metamorphic rocks formed either from such extrusive igneous material or from sedimentary rocks.
* * *▪ geologyscientific discipline concerned with the description of rock successions and their interpretation in terms of a general time scale. It provides a basis for historical geology, and its principles and methods have found application in such fields as petroleum geology and archaeology.Stratigraphic studies deal primarily with sedimentary rocks but may also encompass layered igneous rocks (e.g., those resulting from successive lava flows) or metamorphic rocks formed either from such extrusive igneous material or from sedimentary rocks.A common goal of stratigraphic studies is the subdivision of a sequence of rock strata into mappable units, determining the time relationships that are involved, and correlating units of the sequence—or the entire sequence—with rock strata elsewhere. Following the failed attempts during the last half of the 19th century of the International Geological Congress (IGC; founded 1878) to standardize a stratigraphic scale, the International Union of Geological Sciences (IUGS; founded 1961) established a Commission on Stratigraphy to work toward that end. Traditional stratigraphic schemes rely on two scales: (1) a time scale (using eons, eras, periods, epochs, ages, and chrons), for which each unit is defined by its beginning and ending points, and (2) a correlated scale of rock sequences (using systems, series, stages, and chronozones). These schemes, when used in conjunction with other dating methods—such as radiometric dating (the measurement of radioactive decay), paleoclimatic dating, and paleomagnetic determinations—that, in general, have been developed within the last half of the 20th century, have led to somewhat less confusion of nomenclature and to ever more reliable information on which to base conclusions about Earth history.Because oil and natural gas almost always occur in stratified sedimentary rocks, the process of locating petroleum reservoir traps has been facilitated significantly by the use of stratigraphic concepts and data.An important principle in the application of stratigraphy to archaeology is the law of superposition—the principle that in any undisturbed deposit the oldest layers are normally located at the lowest level. Accordingly, it is presumed that the remains of each succeeding generation are left on the debris of the last.
* * *
Look at other dictionaries:
Stratigraphy — Stratigraphy, a branch of geology, studies rock layers and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy includes two related subfields: lithologic or lithostratigraphy and… … Wikipedia
Stratigraphy — Stra*tig ra*phy, n. [Stratum + graphy.] That branch of geology which treats of the arrangement and succession of strata. [1913 Webster] … The Collaborative International Dictionary of English
stratigraphy — (n.) 1865, from L. strati , comb. form of stratum (see STRATUM (Cf. stratum)) + GRAPHY (Cf. graphy) … Etymology dictionary
stratigraphy — [strə tig′rə fē] n. [< STRATUM + GRAPHY] 1. the arrangement of rocks in layers or strata 2. the branch of geology dealing with the study of the nature, distribution, and relations of the stratified rocks of the earth s crust stratigrapher n.… … English World dictionary
stratigraphy — stratigrafija statusas T sritis ekologija ir aplinkotyra apibrėžtis Geologijos šaka, tirianti Žemės plutą sudarančių uolienų sluoksnių susiklostymo seką, jų savitarpio santykį erdvėje ir santykinį amžių. atitikmenys: angl. stratigraphy vok.… … Ekologijos terminų aiškinamasis žodynas
stratigraphy — noun Etymology: International Scientific Vocabulary Date: 1865 1. geology that deals with the origin, composition, distribution, and succession of strata 2. the arrangement of strata … New Collegiate Dictionary
stratigraphy — noun a) The study of rock layers and the layering process (stratification) b) the layering of deposits, with newer remains overlaying older ones, forming a chronology of the site … Wiktionary
stratigraphy — SYN: tomography. [L. stratum, layer, + G. graphe, a writing] * * * stra·tig·ra·phy strə tig rə fē n, pl phies TOMOGRAPHY * * * stra·tig·ra·phy (strə tigґrə fe) [stratum + graphy] tomography … Medical dictionary
stratigraphy — The branch of geology that deals with the definition and interpretation of layered earth materials; the conditions of their formation; their character, arrangement, sequence, age, and distribution; and especially their correlation by the use… … Glossary of landform and geologic terms
stratigraphy — study of geological layers or strata Sciences and Studies … Phrontistery dictionary