Age (mln years): 167
Coordinates: 56°58′N 43°43′E
Puchezh-Katunki is
a meteor crater in the Chkalovsky District of Nizhny Novgorod Oblast in Volga
Federal District, Russia. It is 80 km (50 mi) in diameter and is estimated to
be 167 ± 3 million years old, placing it in the Middle Jurassic. The crater is
not exposed to the surface, but appears as variation in the vegetation. The central dome,
ring depression, and ring terrace of the 80 km (50 mi) wide impact structure
are nearly completely buried under Neogene and Quaternary sediments, with the
only exposed impactites found on the banks of the Volga River.
9. Chesapeake Bay Crater
Age (mln years): 35.5
Coordinates: 37°17′N 76°1′W
The Chesapeake Bay
impact crater was formed by a bolide that impacted the eastern shore of North America about 35 million years ago, in the late
Eocene epoch. It is one of the best-preserved "wet-target" or marine
impact craters, and the largest known impact crater in the U.S. Continued
slumping of sediments over the rubble of the crater has helped shape Chesapeake Bay.
8. Acraman Crater
Age (mln years): 580
Coordinates: 32°1′S 135°27′E
Acraman crater is a
deeply eroded impact crater in the Gawler
Ranges of South Australia. Its location is marked by Lake Acraman,
a circular ephemeral playa lake about 20 km in diameter. The discovery of
the crater and independent discovery of its ejecta were first reported in the
journal Science in 1986. The evidence for impact includes the presence of shatter
cones and shocked quartz in shattered bedrock on islands within Lake Acraman.
7. Popigai Crater
Age (mln years): 35.7
Coordinates: 71°39′N 111°11′E
The Popigai crater
(or astrobleme) in Siberia, Russia
is tied with Manicouagan Crater as the seventh largest verified impact crater
on Earth. A large bolide impact created the 100 kilometres (62 mi) diameter
crater 35.7 ± 0.2 (2σ) million years ago during the late Eocene (Priabonian
stage). The crater is 300 km east from the outpost of Khatanga and 880 km (550
mi) NE of the city of Norilsk.
It is designated by UNESCO as a Geopark, a site of special geological heritage.
6. Manicouagan
Crater
Age (mln years): 215
Coordinates: 51°23′N 68°42′W
The Manicouagan
Crater is one of the oldest known impact craters on Earth and is located
primarily in Manicouagan Regional County Municipality in the Côte-Nord region
of Québec, Canada, about 300 km (190 mi) north of the city of Baie-Comeau. At
roughly 213-215 million years old, Manicouagan is one of the youngest large
astroblemes visible on the surface. Its northernmost part is located in Caniapiscau Regional County
Municipality. It is thought
to have been caused by the impact of a 5 km (3 mi) diameter asteroid about
215.5 million years ago (Triassic Period). It was once thought to be associated
with the end-Carnian extinction event. The crater is a
multiple-ring structure about 100 km (60 mi) across, with its 70 km (40 mi)
diameter inner ring its most prominent feature; it contains a 70 km (40 mi)
diameter annular lake, the Manicouagan Reservoir, surrounding an inner island
plateau, René-Levasseur Island. It is the earth's sixth largest confirmed
impact crater according to rim-to-rim diameter.
5. Kara Crater
Age (mln years): 70.3
Coordinates: 69°6′N 64°9′E
Kara is a meteor
crater in the Yugorsky Peninsula, Nenetsia,
Russia. It is 65 km in
diameter and the age is estimated to be 70.3 ± 2.2 million years old (Upper
Cretaceous). Impactite outcrops located on the Baydarata Gulf shore north-east
of the crater imply that the original size of the crater, now greatly eroded,
was 120 km in diameter, making it the 4th largest on earth. The crater is not
exposed to the surface.
4. Woodleigh Crater
Age (mln years): 364
Coordinates: 26°3′S 114°40′E
Woodleigh is a
large meteorite impact crater (astrobleme) in Western
Australia, centred on Woodleigh Station east of Shark Bay.
A team of four scientists at the Geological Survey of Western Australia and the
Australian National University,
led by Arthur J. Mory, announced the discovery in the 15 April 2000 issue of Earth
and Planetary Science Letters. The crater is not
exposed at the surface and therefore its size is uncertain. The original
discovery team believe it may be up to 120 km (75 mi) in diameter, but others
argue it may be much smaller, with one study suggesting a diameter closer to 60
km (37 mi). The larger estimate of 120 km, if correct, would make this crater
tied for the fourth largest confirmed impact structure in the world, and imply
a bolide (asteroid or comet) about 5–6 km (3.1–3.7 mi) in diameter. A more
recent study suggest the crater could be between 60 to 160 km or more, and was
produced by a comet or asteroid 6 to 12 km wide.
3. Chicxulub Crater
Age (mln years): 65
Coordinates: 21°20′N 89°30′W
The Chicxulub
crater is a prehistoric impact crater buried underneath the Yucatán Peninsula
in Mexico.
Its center is located near the town of Chicxulub,
after which the crater is named. The age of Chicxulub asteroid impact and the
Cretaceous–Paleogene boundary (K–Pg boundary) coincide precisely, leading to
the conclusion that the cause of the crater was the same cause resulting in the
demise of nonavian dinosaurs on Earth. The crater is more than 180 km (110 mi)
in diameter, making the feature one of the largest confirmed impact structures
on Earth; the impacting bolide that formed the crater was at least 10 km (6 mi)
in diameter.
2. Sudbury Basin
Age (mln years): 1849
Coordinates: 46°36′N 81°11′W
The Sudbury Basin,
also known as Sudbury Structure or the Sudbury Nickel Irruptive, is a major
geologic structure in Ontario,
Canada. It is
the second-largest known impact crater or astrobleme on Earth, as well as one of
the oldest. The basin is
located on the Canadian Shield in the city of Greater
Sudbury, Ontario.
The former municipalities of Rayside-Balfour and
Valley East lie within the Sudbury
Basin, which is referred
to locally as "The Valley". The urban core of the former city of Sudbury lies on the
southern outskirts of the basin. The Sudbury Basin
is located near a number of other geological structures, including the Temagami
Magnetic Anomaly, the Lake
Wanapitei impact crater,
the western end of the Ottawa-Bonnechere Graben, and the eastern end of the
Great Lakes Tectonic Zone although none of the structures are directly related
to each other in the sense of resulting from the same geophysical processes.
1. Vredefort Crater
Age (mln years): 2023
Coordinates: 27°0′S 27°30′E
Vredefort crater is
the largest verified impact crater to have existed on Earth, more than 300 km
across. It was located in the present-day Free State Province of South Africa
and named after the town of Vredefort,
which is situated near its centre. While the crater itself has long since
eroded away, remaining geological structures at its centre are known as the Vredefort
Dome or Vredefort impact structure. In 2005, the Vredefort Dome was added to
the list of UNESCO World Heritage Sites for its geologic interest.
Source :
http://www.worldsbiggests.com
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