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Johannesburg Centre,
Astronomical Society of Southern Africa
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Deo Gloria 2001.01.05 Easter 2000 Expedition Members
The overlap of membership between the two expeditions is a cause for concern. So far, only Lynithe and the writer have attended both. The cumulative experience we should be building is therefore limited, and the program needs to attract individuals with a desire to build experience over a long period of time. The alternative is to attract participants who already have collected meteorites in the field and can share their experience. It is noted with regret that no professional geologists, or representatives of SAHRA have been able to attend either of the expeditions conducted to date. Although the intention is for amateurs to contribute to science, it would be helpful for those with knowledge to assist on site. I am sure that we will be fortunate to have the pleasure of knowledgeable company on future expeditions. The role of the Geology Department of Wits U in analysing sample returns.Expedition members would like to thank the Geology Department, and especially Prof Uwe Reimold, for help both prior to, and after, expeditions conducted in 2000. Additionally, I would like to thank Prof Reimold for taking us seriously and for the handling the additional burden of our ‘meteor-wrong’ samples on his workload so graciously. Acknowledgements The members of the two expeditions conducted in 2000 would like to thank the SAHRA, and especially Mary Leslie, for granting a permit for the collection of meteorites to people who have no experience and are not professionals in that field. Should the SAHRA see fit to issue a further permit, we would be extremely grateful. Forms: Status Originals of the forms have been returned to SAHRA with a letter dated 5 June 2000. Expedition Area The expedition area was to the North of Verneukpan [S29d52m / E21d9m30s]. The farm name is Vaderlandspan. The 1:50 000 map number is 2921cc. The geology map states rock type = PPr [Pietermaritzburg Series shales Dates
The intended search area was Verneukpan where Donald Campbell made a Land Speed Record attempt in 1929. Unfortunately this proved to be under water. [It was still partially muddy and under water during the Spring Expedition]. Subsequent thinking has led us to believe that dry pan surfaces would prove to good for RECENT falls. Older falls would become covered in mud and could sink. We therefore moved North of Verneukpan to a desert pavement surface on the farm Vaderlanspan. The expedition intention was to concentrate on any area likely to have soaked up meteorite falls over a long period of time and to leave them exposed. The underlying shale geology looked likely as a reasonably good contrast area. [Contrast shales with dark rocks with possible fusion crusts]. The geology map proved to be too generic, and one with sufficient detail was not available. In fact, the shales were interspersed with banded iron formations [BIFs] which proved to be a problem. We were sidetracked by the discovery of small stones that were heavy, were attracted by a magnet, and had a shiny black [fusion?] crust. They proved to be BIFs, rich in iron and covered with desert patina. It was hoped that at least one would prove to a meteorite, and while Wits Geology sawed all sample returns open for study, this group proved all to be BIFs. As an aside, the conventional wisdom of hunting for meteorites with a metal detector would have suffered the same fate. Other rock types proved to be lavas. If anything, these samples got my hopes up that one would be meteoritic. One contained visible olivine, had an apparent fusion crust with deep cracks [as mentioned by Dr Mike Zolensky / Johnson Space Centre]. On analysis, one of these also contained nickel, but Wits identified all samples as terrestrial. Karl Sagan stated that "extraordinary claims require extraordinary evidence" and it is right to be quite skeptical in declaring an object to have originated in space. It is suggested that we locate concentration mechanisms close to old surfaces for the next Expedition. It can be assumed that 500 year rains and greater could conceivably move meteorites and other rock from old surfaces and concentrate them in runoff areas. This option has yet to be explored. In conjunction with a move westwards, this could prove to be rewarding. SummaryWhile South Africa’s 50th meteorite remains elusive, the experience gained will pay dividends in future and further explorations. It is felt that any experience gained can be beneficially used in future and therefore the expedition was not wasted, despite the high fuel cost. The lack of success in returning a valid meteorite is probably a function of lack of experience in identifying one in the field. Once the first is found, I predict a spate of finds! Easter 2001, a meteoritical odyssey The next expedition should be conducted to the west of the current permit area [thus necessitating a new permit]. A permit application for an area bounded by Upington, Vredendal, the West coast, and the Namibian border will be made. Should a permit be issued, we should invest in 1:50 000 topographical maps to speed identification of likely sites. This will allow freedom ‘on the ground’ to move to better spots. Therefore a provisional set of dates is proposed here:
The expedition is designed to maximise use of public holidays [ non-revenue earning days!] at a point where the temperatures are neither too hot nor too cold. Please pencil in your diaries now! Some members of the Spring Expedition 2001 would like to extend a visit to the Richtersveld [for those with 4X4s]. I suspect that no permit will be issued to recover meteorites in National Parks, though. [1] There are a number of ‘geological tourist attractions’ to the West including Black Rock, the O’Kiep copper mines, the Steinkopf Reserve area, Gamsberg etc. Trevor Gould | |||||||||||||||||||||||||||||||||||||||
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