Neotectonics
Encyclopedia
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
. 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
, 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.
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. " This approach has been accepted by many researchers.
At the University of Nevada, Reno
Center for Neotectonic Studies, neotectonics is defined as “the study of geologically recent motions of the Earth
's crust
, particularly those produced by earthquake
s, with the goals of understanding the physics
of earthquake recurrence, the growth of mountain
s, 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.
Tectonics
Tectonics is a field of study within geology concerned generally with the structures within the lithosphere of the Earth and particularly with the forces and movements that have operated in a region to create these structures.Tectonics is concerned with the orogenies and tectonic development of...
. It is the study of the motions and deformations of the Earth's crust (geological
Geology
Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which it evolves. Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates...
and geomorphological
Geomorphology
Geomorphology is the scientific study of landforms and the processes that shape them...
processes) which are current or recent in geologic time
Geologic time scale
The geologic time scale provides a system of chronologic measurement relating stratigraphy to time that is used by geologists, paleontologists and other earth scientists to describe the timing and relationships between events that have occurred during the history of the Earth...
. 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
Vladimir Obruchev
Vladimir Afanasyevich Obruchev was a Russian and Soviet geologist who specialized in the study of Siberia and Central Asia. He was also one of the first Russian science fiction authors.- Scientific research :...
, who defined it in his 1948 article as "recent tectonic movements occurred in the upper part of Tertiary
Tertiary
The Tertiary is a deprecated term for a geologic period 65 million to 2.6 million years ago. The Tertiary covered the time span between the superseded Secondary period and the Quaternary...
(Neogene
Neogene
The Neogene is a geologic period and system in the International Commission on Stratigraphy Geologic Timescale starting 23.03 ± 0.05 million years ago and ending 2.588 million years ago...
) and in the Quaternary
Quaternary
The Quaternary Period is the most recent of the three periods of the Cenozoic Era in the geologic time scale of the ICS. It follows the Neogene Period, spanning 2.588 ± 0.005 million years ago to the present...
, 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
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
. 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.
In 1989 Spyros B. Pavlides
Spyros B. Pavlides
Dr. Spyros B. Pavlides is Greek geologist, professor of the Department of Geology and Physical Geography,Aristotle University of Thessaloniki, Greece, vice-president of the School of Geology, AUTh . His primary interests include neotectonics, paleoseismology, archaeoseismology, and use of...
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
Orogeny
Orogeny refers to forces and events leading to a severe structural deformation of the Earth's crust due to the engagement of tectonic plates. Response to such engagement results in the formation of long tracts of highly deformed rock called orogens or orogenic belts...
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. " This approach has been accepted by many researchers.
At the University of Nevada, Reno
University of Nevada, Reno
The University of Nevada, Reno , is a teaching and research university established in 1874 and located in Reno, Nevada, USA...
Center for Neotectonic Studies, neotectonics is defined as “the study of geologically recent motions of the Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
's crust
Crust (geology)
In geology, the crust is the outermost solid shell of a rocky planet or natural satellite, which is chemically distinct from the underlying mantle...
, particularly those produced by earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
s, with the goals of understanding the physics
Geophysics
Geophysics is the physics of the Earth and its environment in space; also the study of the Earth using quantitative physical methods. The term geophysics sometimes refers only to the geological applications: Earth's shape; its gravitational and magnetic fields; its internal structure and...
of earthquake recurrence, the growth of mountain
Mountain
Image:Himalaya_annotated.jpg|thumb|right|The Himalayan mountain range with Mount Everestrect 58 14 160 49 Chomo Lonzorect 200 28 335 52 Makalurect 378 24 566 45 Mount Everestrect 188 581 920 656 Tibetan Plateaurect 250 406 340 427 Rong River...
s, and the seismic
Seismology
Seismology is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other planet-like bodies. The field also includes studies of earthquake effects, such as tsunamis as well as diverse seismic sources such as volcanic, tectonic, oceanic,...
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
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
to the Miocene-Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
boundary.
Further reading
- P. L. HANCOCK and G. D. WILLIAMS, "Neotectonics", Journal of the Geological Society; March 1986; v. 143; no. 2; p. 325-326; (article abstract)