Vepriai crater
Encyclopedia
Vepriai is the largest impact crater
Impact crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...

 in Lithuania
Lithuania
Lithuania , officially the Republic of Lithuania is a country in Northern Europe, the biggest of the three Baltic states. It is situated along the southeastern shore of the Baltic Sea, whereby to the west lie Sweden and Denmark...

, named after the town of Vepriai
Vepriai
Vepriai is the largest town in Ukmergė district, Lithuania, situated south-west of Ukmergė with population of about 1,000 . The capital of Vepriai elderate.-History:Vepriai was founded on a hill near Vepriai Lake and south of Šventoji River...

 located at its center. The crater is not exposed to the surface, having been eroded
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...

 and covered by sedimentary rocks during the last glacial period.

Vepriai crater is 8 km (5 mi) in diameter
Diameter
In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints are on the circle. The diameters are the longest chords of the circle...

 and its age is estimated to be greater than 160 ± 10 million years (Upper Jurassic or earlier). The meteorite struck soft sandstone
Sandstone
Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

 and limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

 rocks thus its initial depth exceeded 500 m (1,640.4 ft) but the site was soon covered by sedimentary rocks, sand
Sand
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...

 and clay
Clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...

. A small lake has formed in the Jurassic period in the impact site.

The crater was reported in 1978, as proven by occurrence of shatter cone
Shatter cone
Shatter cones are rare geological features that are only known to form in the bedrock beneath meteorite impact craters or underground nuclear explosions...

s and impact glass in drill-core samples acquired during a geophysical research of the locality.
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