Photos courtesy of M.Aid & Svend Buhl, text Svend BuhlFirst meteorite finds
Several professional Moroccan meteorite prospectors launched search campaigns immediately after the first reports of a fireball sighting spread.
The terrain in the foothills of the High Atlas is challenging to say the least. Unlike the Hammadahs and Serirs of the Sahara desert it can not be searched by car due to steep ravines, boulder fields and numerous canyons and dry riverbeds with steep cliffs. It took the distinguished hunters two weeks to locate the first fragments by the help of local villagers.
On January 3, 2009 A. Habibi reported the first chondritic finds on the Meteorite Central mailing list. Fragments were sent to scientific institutions and distributed among collectors only days later under the synonyms, "Taliouine", "Ticka" and "Tamdaght".
The weather in the strewn field has changed in the second week of January, from dry cold to rain and storm. Thus search and preservation conditions for the meteorites still in field have worsened. While the first few reported finds displayed no or only minimal signs of oxidation, the finds from the end of January already show some rust staining on the fusion crusted surfaces. As the number of recovered fragments went from two to six it became clear that the bolide had fragmented and produced a strewn field. Many of the reassembled masses show angular shapes indicating that they stem from a larger mother body detonated in flight. The explosion sounds reported by the eye witnesses support the idea of one or more multiple detonations.
As most specimens we have been able to study so far show a thick (0.7 - 1.1 mm) fusion crust. The ablation process must have continued after the fragmentation. However, NO eye witnesses reported multiple fireballs.
The fusion crust of the Tamdakht meteorites shows a rough, vesicular texture and often displays bubbles in the submilimeter scale.
The strewn field
The strewn field was reported to stretch from Tourdjale to Oued. We could not locate these settlements on our topographic maps but we have been sent GPS find locations by three different finders who found a total of 6 masses.
These meteorites have been found 11 - 16 km northeast of the city of Tamdaght, at the far side of the Jebel Tachkoucht. Please note that this data may cover only a part of the actual strewn field.
Approximate trajectory according to eye witness reports and meteorite find location according to finder's GPS data given in red. Map public domain, courtesy of Texas University The meteorite finds were located on the southern flanks of the Jebel Anrhomer whose peak touches the sky at an altitude of 3607 meters. The terrain is shaped by dry river beds with a south orientation, which have cut into the limestone and clay bedrock. The common soil type in the wadis of the Asif Imouten and the Asif Anarhra are aluvial gravels composed of limestone, red sandstone, dolocretes and clay. The higher banks with little or no hydraulic gradient often show a blanket of a dark red laterite soil. The find locations are in altitudes around ~1550 meters. Most masses which have been found until present, including those with weights below 1kg, are commonly broken into many fragments due to the forces of impact.
The horizontal trajectory, shallow impact pits in the loose gravel soil and the total destruction of masses that did not impact rock but clay surfaces, may provide evidence that the meteorites did retain at least some of their cosmic velocity until they hit the ground at an altitude of 1500 meters. At present a total of at ~10 masses totalling ~45kg can be considered confirmed. As most masses were recovered in the shape of many fragments the exact number of recovered specimens is hard to establish. Several other masses of unknown weight have been reported, thus no second source was able to confirm these additional masses, of which one was said to have a weight of ~100kg. The largest mass reported fragmented on impact on the flank of a limestone outcrop and shattered in many pieces. These were distributed in a half circle around the impact site up to a distance of 30 meters. Images that show numerous small fragments of this mass in- situ can be found on the website of Phillipe Thomas.
Several other masses fragmented on impact. Among these a specimen of ~400g of which seven fragments were recovered. After reassembling this meteorite showed the shape of a delta or short boomerang, with thin flanks, but with no apparent signs of orientation (see 2nd image on this page). About 95% of the meteorite was recovered. More or less intact specimens found include a 2007g individual and a 1514g individual, both with impact marks and less than 5% of the mass missing. Cut sections of the Tamdaght meteorite show a chondritic matrix with small chondrules which are hard to spot, particularly on fragmented surfaces. Several of the specimens recovered show slickensides.
We will continue to report information on the Tamdakht meteorite fall here and we appreciate any assist from Morrocan meteorite enthusiasts providing images from the field and information on further finds.
The fusion crust of the Tamdakht meteorites shows a rough, vesicular texture and often displays bubbles in the submilimeter scale.
The strewn field
The strewn field was reported to stretch from Tourdjale to Oued. We could not locate these settlements on our topographic maps but we have been sent GPS find locations by three different finders who found a total of 6 masses.
These meteorites have been found 11 - 16 km northeast of the city of Tamdaght, at the far side of the Jebel Tachkoucht. Please note that this data may cover only a part of the actual strewn field.
Approximate trajectory according to eye witness reports and meteorite find location according to finder's GPS data given in red. Map public domain, courtesy of Texas University The meteorite finds were located on the southern flanks of the Jebel Anrhomer whose peak touches the sky at an altitude of 3607 meters. The terrain is shaped by dry river beds with a south orientation, which have cut into the limestone and clay bedrock. The common soil type in the wadis of the Asif Imouten and the Asif Anarhra are aluvial gravels composed of limestone, red sandstone, dolocretes and clay. The higher banks with little or no hydraulic gradient often show a blanket of a dark red laterite soil. The find locations are in altitudes around ~1550 meters. Most masses which have been found until present, including those with weights below 1kg, are commonly broken into many fragments due to the forces of impact.
The horizontal trajectory, shallow impact pits in the loose gravel soil and the total destruction of masses that did not impact rock but clay surfaces, may provide evidence that the meteorites did retain at least some of their cosmic velocity until they hit the ground at an altitude of 1500 meters. At present a total of at ~10 masses totalling ~45kg can be considered confirmed. As most masses were recovered in the shape of many fragments the exact number of recovered specimens is hard to establish. Several other masses of unknown weight have been reported, thus no second source was able to confirm these additional masses, of which one was said to have a weight of ~100kg. The largest mass reported fragmented on impact on the flank of a limestone outcrop and shattered in many pieces. These were distributed in a half circle around the impact site up to a distance of 30 meters. Images that show numerous small fragments of this mass in- situ can be found on the website of Phillipe Thomas.
Several other masses fragmented on impact. Among these a specimen of ~400g of which seven fragments were recovered. After reassembling this meteorite showed the shape of a delta or short boomerang, with thin flanks, but with no apparent signs of orientation (see 2nd image on this page). About 95% of the meteorite was recovered. More or less intact specimens found include a 2007g individual and a 1514g individual, both with impact marks and less than 5% of the mass missing. Cut sections of the Tamdaght meteorite show a chondritic matrix with small chondrules which are hard to spot, particularly on fragmented surfaces. Several of the specimens recovered show slickensides.
We will continue to report information on the Tamdakht meteorite fall here and we appreciate any assist from Morrocan meteorite enthusiasts providing images from the field and information on further finds.
(Note: this is a summary of Svend`s page 2; to view ALL photos and pages see the links below)
http://www.meteorite-recon.com/en/meteorite%20tamdaght%201.htm
http://www.meteorite-recon.com/en/meteorite%20tamdaght%202.htm
http://www.meteorite-recon.com/en/meteorite%20tamdaght%203.htm
http://www.meteorite-recon.com/en/meteorite%20tamdaght%201.htm
http://www.meteorite-recon.com/en/meteorite%20tamdaght%202.htm
http://www.meteorite-recon.com/en/meteorite%20tamdaght%203.htm
Source: Dr. Svend Buhl, Germany http://www.niger-meteorite-recon.de/ 1FEB09
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