User:Greg Winterflood/Boxhole (meteorite)

In 1937 Joe Webb, a shearer at Boxhole sheep station, took geologist Cecil Madigan to examine the crater. Madigan discovered nickel-bearing metallic fragments and iron shale-balls similar to those found at Henbury to the south of Alice Springs. A later search found additional meteoritic metal including an iron mass of 181 pounds (82 kg) ,[4] now in the Natural History Museum, London.Evidence of the Boxhole (meteorite) was found in crater by the Geologist Cecil Madigan in 1937, on what is now known as Dneiper Station, a cattle property, in the Northern Territory. The main mass of 82kg was not unearthed until later; but proved to be a xxxx class Meteorite Boxhole Meteorite Crater, meteorite crater formed in alluvium near Boxhole Homestead, Northern Territory, central Australia. It is situated 155 miles (250 km) northeast of the Henbury meteorite craters. The bowl-shaped crater, discovered in 1937, is 583 feet (178 m) in diameter and 53 feet (16 m) deep. Numerous nickel–iron fragments have been found in the area. Because of its size, the crater is thought to have resulted from the explosion of a meteorite on impact, although no fused silica glass has been found at the site. ... (88 of 90 words)Iron. Octahedrite, medium (IIIA) “CM” REF: P. 79, “HBIM” REF: P. 338, and “ARN’S” REF: P. 40. The Boxhole Crater is a 170 meter diameter, circular depression, discovered during a geological surveying of the area in June, 1937 near Dneiper (Boxhole) Station. Several large masses of the Boxhole meteorite have been located, including one weighing 82 kg. It has been concluded, from scientific studies of the meteorites found, as well as from investigations of the crater site, that about 5,000 years ago a large iron body apparently penetrated the atmosphere with no appreciable loss of speed. At a high altitude, small parts of the surface of the meteorite, probably protuberances and other irregularities, were torn off and proceeded as independently falling bodies. The main mass exploded upon impact, created the crater, and hurtled numerous fragments up to a distance of a few kilometers away. A study of etched slices of specimens from Boxhole shows that the Widmanstatten lamellae are usually bent and torn out in long stringers, similar to specimens from Henbury. Slicing would probably reveal the distorted structure in all of the uncut examples below. Each is a complete individual, as field collected, with a very thin, reddish-brown, natural oxidized surface. If desired, a minimal amount of cleaning (i.e., with a wire brush) would expose the bright, silvery-metallic color and luster of the unweathered meteoritic material. Pricing is @ +/- $1.50 / gram.

References

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1. “Meteorite Craters”, Kathleen Mark, P. 90 and 100. 2. “Meteorite Craters and Impact Structures of the Earth”, Paul Hodge, P. 62. 3. “Rocks From Space”, First Edition, O. R. Norton, P. 142.

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