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Gibeon Iron Meteorites
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Gibeon Iron Meteorites. Their Discovery, History and Research. By Svend Buhl

The Gibeon meteorite strewnfield today
The total known weight of the recovered meteorites today exceeds 26 tons and the preatmospheric size of the Gibeon body was determined larger than 3 meters (Bajo et al. 2008). More than 74 larger masses (>100 kg) are known today and the number of smaller masses (< 30 kg) collected very probably exceeds 1000. The Gibeon meteorite shower is the 6th largest in total mass known at present.

 

The Gibeon area witnessed fierce fighting, not only 1904/1905 during the Herero war, but also in World War One when the South African Army attacked an outnumbered detachment of the German Colonial Forces near Keetmanshoop and Grotfontein in April and May 1915. Gibeon Station cemetery. Image courtesy of Dr.-Ing. Klaus Dierks
The dimensions of the distribution field are approx. 230 x 115 miles which makes it the largest known meteorite strewn field. In contradiction to other known strewn fields the Gibeon distribution field lacks the typical mass distribution.

Apparently large and smaller masses are spread randomly in the strewn field, with most of the smallest masses concentrated in the central area southeast of Gibeon, where most of the specimens have been found. Obviously the flight parameters of the meteorites were influenced by the kinetics of a significant terminal mid air explosion rather than by the usual aerodynamic forces alone. This way the Gibeon meteorite created rather a distribution fan than an ellipse.

Meteorite prospectors have searched the area since the late 19th century and finds continued until the 1990ies (Ashwal 2001). At Buchwald’s time the locals made little use of metal detectors to prospect for Gibeon meteorites. This changed in the late 1970ies and 1980ies.

With the use of professional equipment also the mass distribution of the specimens recovered changed. Instead of few large masses many small specimens in the pound and kilo range were found. Unfortunately particularly these smaller finds distributed to museums and collectors lack precise find coordinates.

Gibeon meteorites today are widely distributed among museum and private collections. The material is valued not only for its beautiful etch pattern but also for its superior resistance to oxidation.

In 2004 Namibia passed a new National Heritage act and therewith placed an export ban on meteorites. Under these laws it is considered an offence to even uncover or move a Gibeon meteorite from its find location.

Gibeon specimens traded today among meteorite collectors and museums were usually exported from South Africa previous to the independency of Namibia and the current prohibition. Prices for Gibeon material have risen constantly since the export ban was established; from 50 $/kg and below for larger specimens in the 1970ies to 500 $/kg and above at present.

 

Ruins of the German colonial police station of Kub at the bank of the upper Fish River near Kalkrand, Hardap-region. Image courtesy of Dr.-Ing. Klaus Dierks

Field investigation at the site of the finds at present has ceased according to locals, and the current laws regrettably provide little encouragement for the local farmers to map and submit find locations and information on newly discovered meteorites to researchers. Despite the 2004 law, which even restricts any survey or investigation "for the purpose of finding […] a meteorite" (National Heritage Act 2004), it is to be hoped that Citron's expectations on the future research of the Gibeon meteorite strewnfield are fulfilled:

“A thorough field investigation of this area would undoubtly lead to the recovery of many additional tons of meteoritic material and the delineation of the boundaries of this enormous shower.” (Citron 1967)

 

Historic literature on the Gibeon meteorites from the author's collection

Literature

Alexander, J.E.: Report of an Expedition of Discovery, Through the Countries of the Great Namaquas, Boschmans and the Hill Damaras, in South Africa. In: Journ. Roy. Geogr. Soc., 1838, vol. 8, p. 8 ff.

Ashwal, L. D.: Korra Korrabes: A new, large H3 chondrite breccia from Namibia. In: Meteoritics & Planetary Science, vol. 36, no. 8, pp. 1027-1038 (2001)

Bajo, K. et al.: Noble Gases in a Gibeon Iron Meteorite Fragment Heavily Shielded to Cosmic Rays. In: 71st Annual Meeting of the Meteoritical Society, held July 28-August 1, 2008 in Matsue, Japan. Meteoritics and Planetary Science Supplement, Vol. 43, paper id. 5073

Berwerth, F.: Der Meteoreisenzwilling von Mukerop, Bezirk Gibeon, Deutsch-Südwest-Afrika. Extr. from: Sitzungsber. der kaiserl. Akademie der Wiss., vol. CXI, 1902, p.1ff.

Brezina, A.; Cohen, E.: Über ein Meteoreisen von Mukerop, Bezirk Gibeon Grossnamaland. In.: Jahresh. Ver. Vaterländ. Naturk., vol. 58, pp. 292-302

Britt, D.T et al.: Bidirectional reflectance properties of iron-nickel meteorites. In: Lunar and Planetary Science Conference, 18th, Houston, TX, Mar. 16-20, 1987, Proceedings (A89-10851 01-91). Cambridge and New York/Houston, TX, Cambridge University Press/Lunar and Planetary Institute, 1988, p. 503-512.

Buchwald, V.F.: Handbook of Iron Meteorites. Vols. 1-3, Berkeley, 1975

Citron, R.A.: On the Distribution of the Gibeon Meteorites of South-West Africa. 1967

Coetzee, J.A. (Ed.): Palaeoecology of Africa and the Surrounding Islands, vol. 18, Bloemfontein (1987)

Dierks, K. Dr. Ing.: Namibia-Bibliothek. www.klausdierks.com, 1999 – 2004.

Dietz, Robert S.: Roter Kamm, Southwest Africa: Probable Meteorite Crater. In: Meteoritics, Vol. 2, No. 4, June 1965, p. 311ff.

El Goresy et al.: A Petrographic Study of Gibeon and Santa Clara Iron Meteorites: Possible Clues to 107Pd-107Ag Systematics. In: Lunar And Planetary Science XP, 1984, p. 244-245

Fletcher, L.: On Various Masses of Meteoritic Iron Reported to have been found in Great Namaqualand and the Adjacent Region. In: Mineralog. Mag. Vol. 14, 1904, pp. 28-36

Fukuhara, T. et al.: Magnetic contaminations of small iron meteorites, Odessa and Gibeon. In: Antarctic Meteorite Research. Twentysecond Symposium on Antarctic Meteorites, NIPR Symposium No. 11, held June 10-12, 1997, at the National Institute of Polar Research, Tokyo. Editor in Chief, Takeo Hirasawa. Published by the National Institute of Polar Research, 1998, p.178

Golub P et al.: Emission and Ablation of a Large Meteoroid in the Course of Its Motion through the Earth’s Atmosphere. In: Solar System Research, vol. 30, Issue 3 (1986) p.183

Goverment of the Republic of Namibia: National Heritage Act 2004. In: Goverment Gazette, No. 27 (2004), p.1ff.

Grünert, N.: Namibias faszinierende Geologie. Ein Reisehandbuch; Göttingen, 3rd ed., 2003

Hecht, L. et al.: New impact-melt rock from the Roter Kamm impact structure, Namibia: Further constraints on impact age, melt rock chemistry, and projectile composition. In: Meteoritics & Planetary Science, vol. 43, Issue 7, p.1201-1218

Herr, W. et al.: Versuch zur Datierung von Eisenmeteoriten nach der Rhenium- Osmium- Methode. Z. Naturforsch. A16, (1961), pp.1053-1058

Herschel, A.S.: Notice of a Chemical Examination of a Specimen of Native Iron from the East Bank of the Great Fish River, in South Africa. Phil. Mag., vol. 14, 1839, pp. 32-34

Honda, M. et al.: Irradiation Histories of Iron Meteorites, In: Proc. Int. Workshop Advances in Cosmic Ray Science. In: J. Phys. Soc. Jpn. 78 (2009) Suppl. A, pp. 12-17 (2009)

Khazanovich-Wulff, K.K.: A Consistent Spatial Position of the Kimberlite and Meteorite Fields Gibeon and Gross Brukkaros Structures (GB), Namibia: Random or Regular Pattern? In: Meteoritics & Planetary Science, vol. 36, Supplement, p.A97, 2001

Lovering J.F. et al.: Temperatures and mass losses in iron meteorites during ablation in the earth's atmosphere. In: Geochimica et Cosmochimica Acta, vol. 19, Issue 3, (1960) pp.156-158

Malvin, D.J. et al.: Compositional Variations Among Members of the IIIAB Cape York and IVA Gibeon Showers. In: Meteoritics, Vol. 16, 1981, p.353

Matsui,T. et al.: On the Brittle-Ductile Behavior of Iron Meteorites: New Experimental Constraints. In: J. Geophys. Res., Vol. 89, Suppl., 1984, p. C323 - C328

Olejnikov V. P. et al.: On the ablation mechanism of an iron meteorite under the action of a supersonic plasma flux. In: Nizkotemperaturn. plazma v kosmose i na Zemle. Moskva, (1978) p. 277 – 286

Petaev, M.I. et al.: Mineralogy and origin of brassy, sulfide-rich masses in the Gibeon IVA iron. In: 28th Annual Lunar and Planetary Science Conference, 1997, p. 093.

Petaev, M.I. et al.: Mineralogy of Sulfide-bearing Vugs in the Gibeon IVA Iron. In: 28th Annual Lunar and Planetary Science Conference, March 17-21, 1997, Houston, TX, p. 1095

Petaev, M.I. et al.: Cr-bearing Minerals in the Gibeon IVA Iron: Indicators of Sulfur and Oxygen Fugacities in the Parent Body. In: 28th Annual Lunar and Planetary Science Conference, March 17-21, 1997, Houston, TX, 1997, p.1091

Prinz, M. et al.: Silicate Inclusions in Irons and Metal-Silicate Assemblages. In: Lunar and Planetary Science XIII, 1982, p. 632-633

Range, P.: Meteoriten aus Deutsch-Südwestafrika. In: Mitteilungen aus den Deutschen Schutzgebieten, Vol. 26, Dr. H. Marquardsen (Ed.), 1913, p. 341ff.

Scott, E.R.D. et al. : Igneous Evolution of the Core and Mantle in the Parent Body of Group IVA Iron and Stony-Iron Meteorites. In: Meteoritics, vol. 27, no. 3, volume 27, 1992, page 287

Shepard, C.U.: Notice of Lion River, South Africa, Meteoritic Iron. Extr. from: The American Journ. Of Science and Arts, vol. XV, 2nd series, 1853, p. 1f.

Spencer, L.J.: The Gibeon Shower of Meteoritic Irons in South-West Africa. In: Mineralog. Mag., vol. 26, 1941, pp. 19-35

Moller, U. et al.: The IVA Parent Body: Evidence from Silicate-Bearing Group IVA Iron Meteorites. In: Meteoritics, vol. 27, no. 3, volume 27, 1992, page 301

Wasson, J.T.: Impact melting and 182W anomalies in magmatic iron meteorites. In: Meteoritics & Planetary Science 43, 2008, A167

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