The Kamil Meteor Crater (Gilf Kebir region, Egypt)

A rare sample for small-scale meteorite impact craters on Earth

Norbert Brügge, Germany
Dipl.-Geol.

The so named "Kamil Crater" was located during a Google Earth "low flight" (1,000 m above ground level) by Vincenzo De Michele (Istituto Gemmologico Italiano).
The necessary on-site verification of the Kamil Crater was undertaken in the February 2009 expedition by members of Zerzura Club: Massimo Cammelli, Lorenzo De Cola, Vincenzo de Michele, Mario Di Martino, Adriano Furlani, Giancarlo Negro, Gil Ruozzi e Tommaso Vannini.
The thousands of iron meteorite (ataxite rich in nickel) specimens found scattered within the crater and in the surrounding area confirmed the meteoritic impact origin of the crater. The crater is locate at Jebel Kamil, south of Gilf Kebir nearby the Sudanese border. The crater is 45 m in diameter.
A Italian-Egyptian geophysical expedition was then carried out in February 2010 in order to describe this model impact structure and to collect most meteorites specimens in the crater area. The Team identified 5,178 meteoritic fragments totaling 1.7 tons � the biggest single specimen weighs 83 kg

The Kamil Meteor Crater is not related to the widespread crater-shaped structures in the Gilf Kebir region as well as in the Jebel Kamil/northern Sudan. These are much older (28.2 to 26.7 million years) and are of subvolcanic origin.

Published in Meteoritical Bulletin, no. 98, in preparation (2010). Authors are:

L. Folco1, M. Di Martino2, A. El Barkooky3, M. D'Orazio4, A. Lethy5, S. Urbini6,
I. Nicolosi6, M. Hafez5, C. Cordier1, M. van Ginneken1, A. Zeoli1, A. M. Radwan5,
S. El Khrepy5, M. El Gabry5, M. Gomaa5, A. A. Barakat7, R. Serra8, M. El Sharkawi3

1 Museo Nazionale dell'Antartide Universit� di Siena, 53100, Siena, Italy.
2 Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Torino, 10025 Pino Torinese, Italy.
3 Department of Geology, Faculty of Sciences, Cairo University, Giza, Egypt.
4 Dipartimento di Scienze della Terra, Universit� di Pisa, 56126 Pisa, Italy.
5 National Research Institute of Astronomy and Geophysics, Helwan, Egypt.
6 Istituto Nazionale di Geofisica e Vulcanologia, 00143 Roma, Italy.
7 Egyptian Mineral Resources Authority, Abassiya, Cairo, Egypt.
8 Dipartimento di Fisica, Universit� di Bologna, 40126 Bologna, Italy.

Location: 22�01'06''N / 26�05'16''E

  Meteorite

The biggest meteorite specimen found 230 m due north of the crater showing regmaglypts

Polished and etched internal surface  Impct mof shrapnels showing schreibersite inclusions
  

 The geological age of the target-rocks

 
Observations and Conclusions by Stefano Urbini et al, 2012:
"The outcropped 10 m thick sediments at the crater wall consist of layered, pale (top), and reddish brown (bottom), coarse to very coarse-grained, gritty, and ferruginous quartz arenites. The topmost layers are whitish, kaolinitic, and fine-grained. The base of the crater is filled by the impact-breccia, preventing direct investigation of the lower layers of the target rocks.
Seismic data and the surface geology thus indicate that the first 15 m of the preimpact stratigraphic sequence consists of layered sandstones with subhorizontal bedding belonging to the Gilf Kebir Formation, topped by an approximately 2 m thick unconsolidated cover."

My Conclusions:
The Jebel Kamil is known for the widespread outcrop of the Precambrian Basement. According to geological maps are some prominent sandstone hills in the Jebel Kamil  of  lower Cretaceous origin  ("Gilf Kebir Formation�). But the habitus of this brownish sandstones is similar to the sandstones of the northwestern Gilf Kebir (Wadi Talh area) and in a large Clayton Crater, and therefore probably as there also of Carboniferous age. The light sandstones should be of Devonian age. The basement lie deeper and is in this area not to see.

Gilf Kebir (Wadi Talh)			Clayton Crater	Kamil Crater

The Gilf Kebir and Jebel Kamil are the remnants of a once uniform blanket of Paleozoic sandstones. They lie on an uplifted block of the Basement, which is bounded by main-faults. Since the end of the Devonian sedimentation only erosion took place, interrupted only by a  marine nearshore sedimentation in the Carboniferous period. These sediments have filled up valleys between the eroded blocks of the Paleozoic sandstones. Deposits of the Cretaceous period are found only in the Abu Ballas region, in the eastern direction of a presumed main-fault of the uplifted block, where the Basement and Paleozoic sandstones are about 500 m deeper.
Therefore, the target-rocks of the Kamil Meteorite could be Carboniferous layer in such erosional areas.  Finds of plant imprints between 30 and 55 meters above the Basement (incorrectly determined as Cladophlebis and Phlebopteris) suggest a typ of Carboniferous plant (probably the hitherto unknown Paleoweichselia halfa n.sp.).
 The existence of the so-called Gilf Kebir Formation here is very doubtful.