www.niger-meteorite-recon.de
The Tamdaght, Morocco meteorite fall page
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Photos courtesy of M.Aid & Svend Buhl, text Svend Buhl
First 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" "Tamdakhte" and "Tamdaght".
Challenging terrain and worsening weather conditions hamper the search in the Tamdakht meteorite strewn field. Photo courtesy of M.Aid.
The weather in the strewn field did change in the second week of January, from a dry cold to slight rain and storm. Thus
search and preservation conditions for the meteorites still out in the field had 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 halos around the iron aggregates visible on fractured surfaces.
As the number of recovered fragments went from two to ten 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 ore multiple fragmentations.
Individual 399 g Tamdakht meteorite, reassembled from seven fragments. Note the white impact marks
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 well after the fragmentation occurred. However no eye witness did report having seen
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 12 masses.
The documented find locations are given in the map below.
These meteorites have been found 6 - 15 km northwest, north and northeast of the city of
Tamdaght (Tamdakht), at both sides of the Jebel Tachkoucht. By clicking on the map below the
reader may view a lerger map with the distribution ellipse marked.
Please note that this
data at present may cover only a part of the actual strewn field and that several find locations must be considered uncertain
depending further research. (Click in the map to view a large size version)
The larger meteorites (>10 kg) 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 alluvial 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 situated in altitudes of 1500 to 1600 meters.
Many masses which have been found until present, including those with
weights below 1 kg, are commonly broken into many fragments due to the forces of impact.
133 g fragment of the Tamdakht meteorite with prominent impact marks
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 a fraction of their cosmic velocity until they hit the ground at an altitude between
1500 and 1600 meters.
At present (February 2009) a total of at ~13 masses totaling ~77 kg
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 in photo, of
which one was said to have a weight of 87 kg.
The largest mass confirmed until present fragmented on impact on the
flank of a limestone outcrop and was shattered into many hundred pieces. These were
distributed in a half circle around the impact site
up to a distance of 10 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 percent of the meteorite was recovered. Other more or less intact
specimens found include a 3800g, a 2007g individual, a 1514g and a 1407g individual, all
with impact marks and less than 5 percent of their complete mass missing.
Cut sections of the Tamdakht meteorite show a chondritic matrix
with small chondrules which
are hard to spot. Particularly on fragmented surfaces the chondrule patterns
fade with the busy dark ash-grey and blue matrix. Several
of the specimens recovered show slickensides indicating a shock event on the motherbody.
Tamdakht village sign, 6 - 15 km southwest from the strewn field. Photo courtesy of M. Aid.
