Impact craters on Earth

Impact craters on Earth

on earth there are close to 100 impact craters with a diameter of 0.1km or more, many of them either so eroded or large that they can only be recognised on satellite images. for the uninitiated, impact craters are formed by the hypervelocity impact of a meteoroid, asteroid or comet on the earth’s surface (or the surface of any large object in space). i’ve chosen 5 of these incredible craters and used my computer’s keyboard and mouse to present the results below.
any photos i found on flickr are linked to the account.

1. barringer crater, arizona, united states (google maps)

age - 49′000 yrs
diameter - 1.2 km




it’s hard to believe that the photo above is actually of our planet.
probably the most famous crater on earth and also the first on the planet to be recognized as an impact crater, barringer crater in arizona is actually one of the smaller examples with a piddly diameter of 1.2km and depth of 570ft. the impact occured 49′000 years ago.



here’s a flyby of the crater…




2. gosses bluff, northern territory, australia (google maps)

age - 142.5 million yrs
diameter - 5 km



around 142.5 million years ago gosses bluff crater was formed by an object thought to be around 600 metres in diameter. the crater you see today is actually a lot smaller than the original depression due to erosion. its diameter currently stands at 5km, the original diameter thought to have been closer to 20km.



3. vredefort crater, johannesburg, south africa (google maps)

age - 2 billion yrs
diameter - 300 km



with an astounding diameter of around 300km, vredefort basin in south africa is currently the largest confirmed impact crater on earth and also one of the oldest at 2 billion years. the crater was the result of an extreme impact with an object whose diameter was 10km.



4. manicouagan reservoir, quebec, canada (google maps)

age - 212 million yrs
diameter - 72 km



this incredible 72km wide impact crater in quebec has slowly transformed into its current state, what was originally the rim of the crater has since eroded away due to glaciation. the impact occured around 212 million years ago and the diameter of the asteroid is estimated to have been approximately 5km.

you can clearly see the reservoir in the amazing photo below, taken from the international space station during the sts-100 mission.



5. bosomtwe crater, lake bosomtwe, ghana (google maps)

age - 1.2 million yrs
diameter - 10.5 km



the actual impact crater which holds lake bosomtwe is 10.5km in diameter, the lake itself 7km. the impact took place 1 million years ago and since then, due to heavy rainfall, the water level has sometimes spilled over the rim and flooded surrounding areas.



sources: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12

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