The Holleford Crater is a

meteorite A meteorite is a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the atmosphere to reach the surface of a planet or Natural satellite, moon. When the ...

crater Crater may refer to: Landforms *Impact crater, a depression caused by two celestial bodies impacting each other, such as a meteorite hitting a planet *Explosion crater, a hole formed in the ground produced by an explosion near or below the surfac ...

near the community of Holleford, part of

South Frontenac South Frontenac is a township in Frontenac County in eastern Ontario, Canada. It was amalgamated in 1998 from the former townships of Bedford, Loughborough, Portland, and Storrington. The Holleford crater is located in the township near the comm ...

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...

, Canada. It is in

diameter In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle. Both definitions are also valid for ...

and the age is estimated to be 550 ± 100

million One million (1,000,000), or one thousand thousand, is the natural number following 999,999 and preceding 1,000,001. The word is derived from the early Italian ''millione'' (''milione'' in modern Italian), from ''mille'', "thousand", plus the au ...

years (

Ediacaran The Ediacaran Period ( ) is a geological period that spans 96 million years from the end of the Cryogenian Period 635 million years ago (Mya), to the beginning of the Cambrian Period 538.8 Mya. It marks the end of the Proterozoic Eon, and th ...

Cambrian The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million ...

). Although there is a surface depression over the area, the crater itself is not exposed at the surface. Holleford Crater was discovered in the 1950s during analysis of

aerial photographs Aerial photography (or airborne imagery) is the taking of photographs from an aircraft or other airborne platforms. When taking motion pictures, it is also known as aerial videography. Platforms for aerial photography include fixed-wing aircra ...

under the direction of Carlyle S. Beals of the

Dominion Observatory The Dominion Observatory was an astronomical observatory in Ottawa, Ontario that operated from 1902 to 1970. The Observatory was also an institution within the Canadian Federal Government. The observatory grew out of the Department of the Int ...

Ottawa Ottawa (, ; Canadian French: ) is the capital city of Canada. It is located at the confluence of the Ottawa River and the Rideau River in the southern portion of the province of Ontario. Ottawa borders Gatineau, Quebec, and forms the core ...

. In the late 1950s, the

Geological Survey of Canada The Geological Survey of Canada (GSC; french: Commission géologique du Canada (CGC)) is a Canadian federal government agency responsible for performing geological surveys of the country, developing Canada's natural resources and protecting the en ...

conducted a series of four

geophysical Geophysics () is a subject of natural science concerned with the physical processes and physical properties of the Earth and its surrounding space environment, and the use of quantitative methods for their analysis. The term ''geophysics'' som ...

studies:

magnetic Magnetism is the class of physical attributes that are mediated by a magnetic field, which refers to the capacity to induce attractive and repulsive phenomena in other entities. Electric currents and the magnetic moments of elementary particle ...

observations,

seismic Seismology (; from Ancient Greek σεισμός (''seismós'') meaning "earthquake" and -λογία (''-logía'') meaning "study of") is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other ...

studies,

gravity In physics, gravity () is a fundamental interaction which causes mutual attraction between all things with mass or energy. Gravity is, by far, the weakest of the four fundamental interactions, approximately 1038 times weaker than the stro ...

studies, and a

diamond drilling Exploration diamond drilling is used in the mining industry to probe the contents of known ore deposits and potential sites. By withdrawing a small diameter core of rock from the orebody, geologists can analyze the core by chemical assay and cond ...

program. The seismic and gravity studies and the drilling all produced data consistent with the impact theory. The

drill core A modern core drill is a drill specifically designed to remove a cylinder of material, much like a hole saw. The material left inside the drill bit is referred to as the ''core''. Core drills used in metal are called annular cutters. Core dri ...

revealed

breccia Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix. The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of di ...

and similar materials at predicted depths. The studies concluded that an ancient meteorite impact crater is present in the

Precambrian The Precambrian (or Pre-Cambrian, sometimes abbreviated pꞒ, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the ...

bedrock below the surface. The meteorite was estimated to be approximately in diameter and to have impacted at approximately .

Location

Holleford Crater is located on the Babcook Family Homestead Farm properties (including the original Babcook Homestead Farm, established 1803, owned by the family of the late Frederick and Jean Babcook, at

Hartington, Ontario Hartington is a small village in South Frontenac Township, located about 14.5 miles (23.3 km) north of Kingston, Ontario, Canada on Provincial Route 38 (previously Highway 38). It was formerly a stop on the Kingston and Pembroke Railway The ...

(about 1/2 hour north of

Kingston Ontario Kingston is a city in Ontario, Canada. It is located on the north-eastern end of Lake Ontario, at the beginning of the St. Lawrence River and at the mouth of the Cataraqui River (south end of the Rideau Canal). The city is midway between Toron ...

). (It was the birthplace of the last surviving veteran of the Canadian army in World War One, Jack Babcock, who died on February 18, 2010, at the age of 109.) Starting in the 1960s, the site has been visited frequently by geology students from Queen's University, at Kingston. In the 1970s, as a result of efforts by the late Frederick Babcook, an official commemorative plaque was erected along the road beside the Babcook Homestead Farm by the Province of Ontario. Queen's University's Miller Hall Museum of Geology maintains a display dedicated to the Holleford Meteorite Crater.

References

External links

Aerial Exploration of the Holleford Structure
{{Impact cratering on Earth Impact craters of Ontario Proterozoic impact craters Landforms of Frontenac County