Quaternary period


Also found in: Dictionary, Thesaurus, Medical, Wikipedia.
Related to Quaternary period: Tertiary period, Neogene Period

See also: Geologic Timescale (table)Geologic Timescale
Era Period Epoch Approximate duration
(millions of years)
Approximate number of years ago
(millions of years)

Cenozoic Quaternary Holocene 10,000 years ago to the present  
Pleistocene 2 .
..... Click the link for more information.

Quaternary period

(kwətûr`nərē), younger of the two geologic periods of the Cenozoic eraCenozoic era
, last major division of geologic time (see Geologic Timescale, table) lasting from 65 million years ago to the present. The Cenozoic is divided into the Tertiary (from 65 million years ago until 2 million years ago) and Quaternary (2 million years ago to the
..... Click the link for more information.
 of geologic time (see Geologic TimescaleGeologic Timescale
Era Period Epoch Approximate duration
(millions of years)
Approximate number of years ago
(millions of years)

Cenozoic Quaternary Holocene 10,000 years ago to the present  
Pleistocene 2 .
..... Click the link for more information.
, table) from 2 millon years ago to the present. Comprising all geologic time from the end of the Tertiary periodTertiary period
, name for the major portion of the Cenozoic era, the most recent of the geologic eras (see Geologic Timescale, table) from around 26 to 66 million years ago. The name Tertiary was first applied about the middle of the 18th cent.
..... Click the link for more information.
 to the present, it is divided into the PleistocenePleistocene epoch
, 6th epoch of the Cenozoic era of geologic time (see Geologic Timescale, table). According to a classification that considered its deposits to have been formed by the biblical great flood, the epoch was originally called the Quaternary.
..... Click the link for more information.
 and HoloceneHolocene epoch
or Recent epoch,
most recent of all subdivisions of geologic time, ranging from the present back to the time (c.11,000 years ago) of almost complete withdrawal of the glaciers of the preceding Pleistocene epoch.
..... Click the link for more information.
, or Recent, epochs. It was named (1759) by Giovanni Arduino, an Italian scientist who thought that the biblical great flood was responsible for its deposits. During the early Quaternary, Europe and North America were covered by the glaciers of the Pleistocene epochPleistocene epoch
, 6th epoch of the Cenozoic era of geologic time (see Geologic Timescale, table). According to a classification that considered its deposits to have been formed by the biblical great flood, the epoch was originally called the Quaternary.
..... Click the link for more information.
. Retreat of the glaciers led to isostatic rebound (see continentcontinent,
largest unit of landmasses on the earth. The continents include Eurasia (conventionally regarded as two continents, Europe and Asia), Africa, North America, South America, Australia, and Antarctica.
..... Click the link for more information.
) of the crust in the Holocene. In the Quaternary the climate and present physical features of the earth continued to develop. Significant changes in sea level within historic times are demonstrated by the submergence of the temple of Jupiter Serapis near Naples and by the rising of the shores of the Baltic. The life of the Quaternary has been marked by the rise and dominance of humans.
References in periodicals archive ?
In the Neotropical regions during the Quaternary period, there were periods of high annual precipitation followed by the expansion of forest formations.
Thus, during the Quaternary period, higher plateaus could have locally concentrated precipitations that preserved local wetness (Oliveira Filho and Ratter, 2000; Pennington et al., 2000) and favoured the existence of forest formations.
They create at a view of lowland neotropical vegetation alternating between closed forest and more dry open forest or savanna-like vegetation during the environmental fluctuations of the late Tertiary and Quaternary Period."
tectonic uplift or subsidence, over large regions or by more localized (orogenic) mountain building during the last 60 million years (Cenozoic era; Tertiary and Quaternary periods) and before; or these changes were caused by fluctuations of world sea-level leading to repeated flooding (and subsequent falling dry) of low lying areas in Amazonia and on the continental shelves.
Five cores collected on ODP Leg 130 (in 1990) at Site 806 provide an excellent record of ice-mass fluctuations over the last two million years (the Quaternary period).
Other researchers agree that during some times (such as the Quaternary period starting 2 million years ago) the waxing and waning of ice sheets has triggered third-order sea level falls and rises.
Controversy over when exactly the Quaternary Period began has raged for decades, with attempts in 1948 and 1983 to define the era.
His research has focused on the Quaternary period (the past 1.8 million years), identifying glacial and interglacial climatic cycles in marine sediment, examining the role of carbon dioxide in ancient climate change and linking variation in the Earth's orbit to predictions of future climate change.
During the past 25 years, the ocean drilling programs have recovered numerous shallow carbonate sequences, ranging in age from the late Triassic (230 million years ago) to the Quaternary period (the last 1.6 million years), along continental passive margins and aseismic volcanic ridges in intra-oceanic basins.

Full browser ?