[meteorite-list] Possible Sudanese Extraterrestrial Impact Crater Reexamined
From: Paul H. <oxytropidoceras_at_meteoritecentral.com>
Date: Thu, 10 Nov 2011 15:22:50 -0600 Message-ID: <20111110162250.DND22.18814.imail_at_eastrmwml41> Sparavigna (2010) conducted a survey of the Bayuda desert region in Sudan using satellite images from Google Maps. As a result of this survey and the use of AstroFracTool to enhance edges without loosing the "whole texture" of the image, they recognized a 10-km in diameter "crater-like landform" about 40 km west of Berber town at 18? 3' 25.52" N, 33? 30.22 W. Because of lack of information, Sparavigna (2010) noted that the origin, i.e. volcanic, hypervelocity impact, or other, of the crater-like landform remains unresolved. Both Anonymous(2010) and McNally (2010) reported this feature as being a brand new, undiscovered "crater." McNally (2010) also stated that "no one has gone to the Bayuda crater site to confirm that it was formed by a meteor impact." Contrary to what is stated by Sparavigna (2010), Anonymous (2010), and McNally (2010), this feature was discovered and investigated years before 2010. This feature was studied and mapped by Barth and Meinhold (1979, 1981) and Brath et al. (1983). The geology of this feature is also summarized and illustrated in Woolley (2001). These publications demonstrate that this feature is, as classified by the Earth Impact Database by David Rajom, a class 5 feature that is neither an extraterrestrial impact structure nor crater. Instead it is an igneous intrusion. According to Woolley (2001), this feature is the Singeir igneous ring complex. This intrusive complex is 15 km in diameter. To the northeast of it lies the smaller Kurbei igneous intrusion. The Singeir igneous ring complex consists of arcuate intrusions of sodic amphibole granite that contain stringers of biotite- hornblende granite (Barth and Meinhold, 1979, 1981; Brath et al., 1983; Woolley, 2001). References Cited, Anonymous, 2010, New Desert Crater Found Using Google Maps and Free Software. Physics arXiv Blog, MIT Technology Review, Massachusetts Institute of Technology, Cambridge, Massachusetts (August 10, 2010) http://www.technologyreview.com/blog/arxiv/25583/ Barth, H. and K.-D. Meinhold, 1979. Mineral prospecting in the Bayuda Desert. Part " Volume A. Investigation of mineral potential. Technical Rcport Sudanese-German Exploration Project. Hannover (Bundesanstalt fur Geowissenschaften und Rohstoffe ). Barth, H. and K.-D. Meinhold, 1981, Geological map of the Bayuda Desert, Sudan. 1:250,000. Bundesanstalt fur Geowissenschaften und Rohstoffe, Hannover and Geological and Mineral Resources Department, Khartoum. Barth, H., C. Besang, H. Lenz, and K.-D. Meinhold, 1983, Results of petrological investigations and RblSr age determinations on the non-orogenic igneous ring-complexes in the Bayuda Desert, Sudan. Geologisches Jahrbuch. v. 51, pp. 1-34. McNally, J., 2010, Asteroid Crater Hunting From Your Home. Wired Science (August 10, 2010) http://www.wired.com/wiredscience/2010/08/crater-hunting/ Sparavigna, A. C., 2010, Crater-like landform in Bayuda desert (a processing of satellite images). arXiv:1008.0500v1 [physics.geo-ph], Cornell University Library, Ithaca New York http://arxiv.org/abs/1008.0500 Woolley, A. R., 2001, Alkakline Rocks and Carbonatites of the World, Part 3: Africa. London, United Kingdom, The Geological Society of London. Yours, Paul H. Received on Thu 10 Nov 2011 04:22:50 PM PST |
StumbleUpon del.icio.us Yahoo MyWeb |