Tethys Ocean (Ancient Greek: Τηθύς), Tethys Sea or Neotethys
was an ocean during much of the
Mesozoic Era located between the
ancient continents of
Gondwana and Laurasia, before the opening of the
Indian and Atlantic oceans during the
2 Terminology and subdivisions
3 Modern theory
3.3 Late Cretaceous
4 Historical theory
5 See also
The name stems from the mythological Greek sea goddess Tethys, sister
and consort of Oceanus, mother of the great rivers, lakes, and
fountains of the world and of the
Oceanid sea nymphs.
Terminology and subdivisions
The eastern part of the
Tethys Ocean is sometimes referred to as
Eastern Tethys. The western part of the
Tethys Ocean is called Tethys
Sea, Western Tethys Ocean, or
Paratethys or Alpine Tethys Ocean. The
Black, Caspian, and Aral seas are thought to be its crustal remains,
Black Sea may, in fact, be a remnant of the older
Paleo-Tethys Ocean. The Western Tethys was not simply a single open
ocean. It covered many small plates,
Cretaceous island arcs, and
microcontinents. Many small oceanic basins (Valais Ocean,
Piemont-Liguria Ocean, Meliata Ocean) were separated from each other
by continental terranes on the Alboran, Iberian, and Apulian plates.
The high sea level in the
Mesozoic flooded most of these continental
domains, forming shallow seas. As theories have
improved, scientists have extended the "Tethys" name to refer to three
similar oceans that preceded it, separating the continental terranes:
in Asia, the
Paleo-Tethys (Devonian–Triassic), Meso-Tethys (late
Early Permian–Late Cretaceous), and Ceno-Tethy
(Late-Triassic–Cenozoic) are recognized. Neither Tethys Ocean
should be confused with the Rheic Ocean, which existed to the west of
them in the
Silurian Period. To the north of the Tethys, the
then-land mass was called
Angaraland and to the south of it, it was
called Gondwanaland.
Ediacaran (600 Mya) into the
Devonian (360 Mya), the
Proto-Tethys Ocean existed and was situated between
Laurentia to the north and
Gondwana to the south.
Silurian (440 Mya) through the
Jurassic periods, the
Paleo-Tethys Ocean existed between the Hunic terranes and Gondwana.
Over a period of 400 million years, continental terranes
intermittently separated from
Gondwana in the Southern Hemisphere to
migrate northward to form Asia in the Northern Hemisphere.
Plate tectonic reconstruction of the Tethys realm at 249 Mya
About 250 Mya, during the Triassic, a new ocean began forming in
the southern end of the
Paleo-Tethys Ocean. A rift formed along the
northern continental shelf of Southern
Pangaea (Gondwana). Over the
next 60 million years, that piece of shelf, known as Cimmeria,
traveled north, pushing the floor of the
Paleo-Tethys Ocean under the
eastern end of northern
Pangaea (i.e.Laurasia). The Tethys Ocean
formed between Cimmeria and Gondwana, directly over where the
Paleo-Tethys used to be.
Jurassic period about 150 Mya, Cimmeria finally collided
Laurasia and stalled, so the ocean floor behind it buckled under,
forming the Tethyan Trench. Water levels rose, and the western Tethys
shallowly covered significant portions of Europe, forming the first
Tethys Sea. Around the same time,
Gondwana began drifting
apart, opening an extension of the Tethys Sea between them which today
is the part of the
Atlantic Ocean between the
Mediterranean and the
Caribbean. As North and South America were still attached to the rest
Laurasia and Gondwana, respectively, the
Tethys Ocean in its widest
extension was part of a continuous oceanic belt running around the
Earth between about latitude 30°N and the Equator. Thus, ocean
currents at the time around the Early
Cretaceous ran very differently
from the way they do today.
Plate tectonic reconstruction of the Tethys realm at 100 Mya
Jurassic and the Late Cretaceous, which started about 100
Gondwana began breaking up, pushing Africa and India north across
the Tethys and opening up the Indian Ocean. As these land masses
crowded in on the
Tethys Ocean from all sides, to as recently as the
Late Miocene, 15 Mya, the ocean continued to shrink, becoming the
Tethys Seaway or second Tethys Sea. Throughout the
million to the dawn of the Neogene, 23 Mya), global sea levels fell
hundreds of meters, and eventually the connections between the
Atlantic and the Tethys closed off in what is now the Middle
Oligocene (33.9 to 23 Mya), large parts of central and
eastern Europe were covered by a northern branch of the Tethys Ocean,
called the Paratethys. The
Paratethys was separated from the Tethys
with the formation of the Alps, Carpathians, Dinarides, Taurus, and
Elburz mountains during the Alpine orogeny. During the late Miocene,
Paratethys gradually disappeared, and became an isolated inland
Today, India, Pakistan, Indonesia, and the
Indian Ocean cover the area
once occupied by the Tethys Ocean, and Turkey, Iraq, and Tibet sit on
Cimmeria. What was once the western arm of the Tethys Sea was the
ancestor of the present-day
Mediterranean Sea. Other remnants are the
Black, Caspian, and Aral Seas via a former inland branch known as the
Paratethys. Most of the floor of the
Tethys Ocean disappeared under
Cimmeria and Laurasia.
Eduard Suess have found fossils of ocean
creatures in rocks in the Himalayas, indicating that those rocks were
once under water, before the Indian continental shelf began pushing
upward as it collided with Cimmeria.
Similar geologic evidence can be seen in the
Alpine orogeny of Europe,
where the movement of the
African plate raised the Alps. Greece and
Levant also retain many units of limestone and other sedimentary
rocks deposited by various stands of the Tethys Ocean.[citation
Paleontologists find the
Tethys Ocean particularly important, because
many of the world's sea shelves were found around its margins for such
an extensive length of time with marine, marsh-dwelling, and estuarian
fossils from these shelves. The Solnhofen limestone
in Bavaria, originally a coastal lagoon mud of the Tethys Ocean,
yielded the famous
Eduard Suess in 1869
In 1885, the Austrian palaeontologist
Melchior Neumayr deduced the
existence of the
Tethys Ocean from
Mesozoic marine sediments and their
distribution, calling his concept Zentrales Mittelmeer and described
it as a
Jurassic seaway, which extended from the
Caribbean to the
In 1893, the Austrian geologist
Eduard Suess proposed the theory that
an ancient and extinct inland sea had once existed between Laurasia
and the continents which formed
Gondwana II. He named it the Tethys
Sea after the Greek sea goddess Tethys. He provided evidence for his
theory using fossil records from the Alps and Africa. He proposed
the concept of Tethys in his four-volume work Das Antlitz der Erde
(The Face of the Earth).
In the following decades during the 20th century, "mobilist"
geologists such as Uhlig (1911), Diener (1925), and Daque (1926)
regarded Tethys as a large trough between two supercontinents which
lasted from the late Palaeozoic until continental fragments derived
Gondwana obliterated it.
After World War II, Tethys was described as a triangular ocean with a
wide eastern end.
From 1920s to the 1960s, "fixist" geologists, however, regarded Tethys
as a composite trough, which evolved through a series of orogenic
cycles. They used the terms 'Paleotethys', 'Mesotethys', and
'Neotethys' for the Caledonian, Variscan, and Alpine orogenies,
respectively. In the 1970s and '80s, these terms and 'Proto-Tethys',
were used in different senses by various authors, but the concept of a
single ocean wedging into Pangea from the east, roughly where Suess
first proposed it, remained.
In the 1960s, the theory of plate tectonics became established, and
Suess's "sea" became clearly to have been in fact an ocean. Plate
tectonics provided an explanation for the mechanism by which the
former ocean disappeared: oceanic crust can subduct under continental
Tethys was considered an oceanic plate by Smith (1971); Dewey, Pitman,
Ryan and Bonnin (1973); Laubscher and Bernoulli (1973); and
Bijou-Duval, Dercourt and Pichon (1977).
^ Van der Voo, Rob (1993). Paleomagnetism of the Atlantic, Tethys and
Iapetus Oceans. Cambridge University Press. doi:10.2277/0521612098.
^ a b Metcalfe 2013, Introduction, p. 2
^ Stampfli & Borel 2002, Figs. 3–9
^ Palaeos Mesozoic: Triassic: Middle
Triassic Archived May 16, 2008,
at the Wayback Machine.
^ Kollmann 1992
^ Suess 1893, p. 183: "This ocean we designate by the name
"Tethys" after the sister and consort of Oceanus. The latest successor
of the Tethyan Sea is the present Mediterranean."
^ Suess 1901, Gondwana-Land und Tethys, p. 25: "Dasselbe wurde von
Neumayr das 'centrale Mittelmeer' genannt und wird hier mit dem Namen
Tethys bezeichnet werden. Das heutige europäische Mittelmeer ist ein
Rest der Tethys."
^ Metcalfe 1999, How many Tethys Oceans?, pp. 1–3
Kollmann, H. A. (1992). "Tethys—the Evolution of an Idea". In
Kollmann, H. A.; Zapfe, H. New Aspects on Tethyan
Assemblages. Springer-Verlag reprint ed. 1992. pp. 9–14.
ISBN 978-0387865553. OCLC 27717529. Retrieved 6 October
Metcalfe, I. (1999). "The ancient Tethys oceans of Asia: How many? How
old? How deep? How wide?". UNEAC Asia papers. 1: 1–9. Retrieved 6
Metcalfe, I. (2013). "
Gondwana dispersion and Asian accretion:
tectonic and palaeogeographic evolution of eastern Tethys" (PDF).
Journal of Asian Earth Sciences. 66: 1–33.
doi:10.1016/j.jseaes.2012.12.020. Retrieved 6 October 2015.
Stampfli, G. M.; Borel, G. D. (2002). "A plate tectonic model for the
Mesozoic constrained by dynamic plate boundaries and
restored synthetic oceanic isochrons" (PDF). Earth and Planetary
Science Letters. 196 (1): 17–33. doi:10.1016/S0012-821X(01)00588-X.
Retrieved 6 October 2015.
Suess, E. (1893). "Are ocean depths permanent?". Natural Science: A
Monthly Review of Scientific Progress. 2. London. pp. 180– 187.
Retrieved 6 October 2015.
Suess, E. (1901). Der Antlitz der Erde (in German). 3. Wien F.
Tempsky. Retrieved 6 October 2015.
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