Neotectonics

Neotectonics is a subdiscipline of tectonics. It is the study of the motions and deformations of the Earth's crust (geological and geomorphological processes) which are current or recent in geologic time.^[1] The term may also refer to the motions/deformations in question themselves. The corresponding time frame is referred to as the neotectonic period. Accordingly, the preceding time is referred to as palaeotectonic period.

The term is attributed to Vladimir Obruchev,^[2] who defined it in his 1948 article as "recent tectonic movements occurred in the upper part of Tertiary (Neogene) and in the Quaternary, which played an essential role in the origin of the contemporary topography". Since then there has been a disagreement as to how far back in time "geologically recent" is, with the common meaning being that neotectonics is the youngest, not yet finished stage in Earth tectonics. Some authors consider neotectonics to be basically synonymous with "active tectonics", while others start the neotectonic period from the middle miocene. A general agreement has been emerging that the actual time frame may be individual for each geological environment and it must be set back in time sufficiently far to fully understand the current tectonic activity.^[3]

In 1989 Spyros B. Pavlides suggested the following definition: "Neotectonics is the study of young tectonic events which have occurred or are still occurring in a given region after its orogeny or after its last significant tectonic set-up"..."The tectonic events are recent enough to permit a detailed analysis by differentiated and specific methods, while their results are directly compatible with seismological observations. "^[4] This approach has been accepted by many researchers.^[3]

At the University of Nevada, Reno Center for Neotectonic Studies,^[5] neotectonics is defined as “the study of geologically recent motions of the Earth's crust, particularly those produced by earthquakes, with the goals of understanding the physics of earthquake recurrence, the growth of mountains, and the seismic hazard embodied in these processes.”

Another source of different interpretations for a region is that changes in different tectonic plates of the region may occur at different times, giving rise to the notion of the "transitional time", during which both palaeotectonic and neotectonic features coexist. For example, for central/northern Europe, the transitional period stretches from the middle early Miocene to the Miocene-Pliocene boundary. ^[6]

References

1. ^ "Encyclopedia of Coastal Science" (2005), Springer, ISBN 978-1-4020-1903-6, Chapter 1: "Tectonics and Neotectonics" doi:10.1007/1-4020-3880-1
2. ^ V.A. Obruchev (1948). "Osnovnye cherty kinetiki i plastiki neotektonik". Izv. Akad. Nauk, Ser. Geol., 5: 13-24,
3. ^ ^{a b} Eduard A. Koster (2005) "The Physical Geography of Western Europe", ISBN 0199277753, Ch. 2: Neotectonics
4. ^ Spyros B. Pavlides (1989) "Looking for a definition of neotectonics", Terra Nova, Vol. 1 Issue 3, pp. 233-235 doi:10.1111/j.1365-3121.1989.tb00362.x
5. ^ University of Nevada, Reno. "Center for Neotectonic Studies". http://neotectonics.seismo.unr.edu/CNSHome.html. 
6. ^ A. Becker, " An attempt to define a “neotectonic period” for central and northern Europe", International Journal of Earth Sciences, Volume 82, Number 1, 1993 doi:10.1007/BF00563271

Further reading

• P. L. HANCOCK and G. D. WILLIAMS, "Neotectonics", Journal of the Geological Society; March 1986; v. 143; no. 2; p. 325-326; doi:10.1144/gsjgs.143.2.0323 (article abstract)

See also

Seismic hazard