"Qaret-el-Hanash" structure in the Western Desert (Egypt)
(Probably the first detected
Kimberlite pipe nearby the Silica strewnfield)

 Norbert Brügge, Germany
Dipl.-Geol.

Upload: April 2018
Update:
13.10.2018


The Qaret-el-Hanash is a prominent doming structure with a wall on top in the southeast direction of the Libyan Desert Glass area. The hight of the hill is 96 m above ground. The slopes of the elevation are covered with broken sandstones.
During an expedition in 1996 traces of an eroded zone of megascopic sandstone breccia, of about 2-m thickness, have been recognized. The breccia occurs within the wall of Qaret-el-Hanash. Its matrix appears as dull greyish-black material.
Petrographical and mineralogical studies have shown that there are breccias, that consists of local sandstone rock fragments within a matrix of finer quartz grains with glass and several other mineral phases. The results were published in 2004 and declared as evidence of the emergence of Qaret-el- Hanash by an impact.
(Aly Barakat)

However, the most important indication for the emergence of Qaret-el-Hanash, which I postulate now as a kimberlite pipe, are the photos of
Ursula Steiner (Switzerland), which come from the top and southwestern outside slope of the structure and are available to me.
The photos document clear the volcanic origin of Qaret-el-Hanash impressively. The structure is crater-shaped, as it occurs in the Gilf Kebir Crater Field (GKCF), but without (and that is the significant difference) the tilted layers on the edge, indicating an explosion event.



25°04'46"N / 25°56'02"E

 It seems that the most visibly material of the structure is burned sandstone. But some photos from the debris outside (below) also show a strange material of a dark (carbonaceous ?) melt with included many diverse fragments, among ferruginous pieces, debris of basement (BIF), glass, yellow jasper and minerals. The melt contain also visible large dark brown diamonds. The whole composition is chaotic.
Important to mention are the intersecting (tectonic) dark lines visible from the air on the southwestern slope of the structure, where the melt with breccias and diamonds were found.


Photos by Ursula Steiner (2012)
The exact coordinates are known to the author. All photos are available in high resolution

  

Top of the Qaret-el-Hanash: Jasper on ferruginous sandstone

Unexplored crater bottom

Breccia

Breccia outside slope

Quartz flow with cracks

Glass

  Diamonds (or Moissanite ?)  

Dark (carbonaceous ?) melt Jasper  



 


Mysterious dark (tectonic?) crosscut lines on the southern slope of the structure


DISCOVERY OF Fe-Cr-Ni SPECKS WITHIN QARET EL-HANASH BRECCIA OF THE LIBYAN GLASS AREA SOUTH WESTERN EGYPT
A. El-Kammar, I. Arafa, K. A. Soliman & A. Barakat --7th International Conference on the Geology of the Arab World, Cairo University, Feb. 2004, P. 1-7


The rock consists of various fragments of local sandstone, i.e., from the area of the glass distribution itself. Fragments of igneous source have never been recorded. The rock fragments range from fraction of mm up to 4-cm in diameter, in the collected specimens. The rock fragments vary in colour from creamy white to brownish-red. They are angular to subrounded and embedded in a dull greyish-black matrix. The microscopic investigation and scanning electron microanalysis confirmed the above-mentioned observation and showed that the matrix consists of shattered and fragmented quartz grains of various sizes. In addition to quartz, the matrix contains many other phases, such as glass, zircon, clay minerals, wollastonite, ilmenite, Mg-ilmenite, rutile and Fe-Cr-Ni specks.

There are several metallic specks of various sizes ranging from 1 micron up to about 10 micron, dispersed in the matrix of Qaret el Hanash breccia. They invade some of the quartz grains. These specks are mainly of irregular outlines and some of them show clear fissures. They are associated with glass and intercalated in some cases with halite. EDAX analyses of such specks indicate that they consist of native Fe, Cr and Ni, in addition to subordinate Si and Ca. Finer particles of similar appearance have also been noticed by the petrographical microscope through the fractures of some of the quartz grains.

The most interesting achievement of the chemical analyses is the detection of high Ir content (2.0-2.2 ppb) within the breccias. This value represents the highest reported values for the area. The reported value of Ir in other breccias in the area is around 1.6-1.9 ppb. The highest reported concentration of Ir by the previous studies was detected from the black streak portions from the Libyan glass itself is 1.25 ppb. (Barakat 2018)
Personal information by Aly Barakat on May 19, 2018: Samples of other phases includes tiny grains of moissanite and diamond.

 

Micro-diamonds
 in Qaret-el-Hanash breccia
Source: E.Diemer (2003)
The analysis of the glassy matrix confirm a similarity to the
 dark LDG variety
Thanks to Aly Barakat
Photomicrograph breccia showing shattered and fragmented quartz grains in the glassy matrix admixed with other phases SEM image and EDS analysis of quartz and glass of worm like structure in the matrix Photomicrograph showing finer particles of the Fe-Cr-Ni phase dispersed within the glassy matrix

 


In Addition:
 

1.) The so-called Siwa-meteorite (not Serra's 36g chondrite) is a breccia-bearing sandstone similar to the Qaret-el-Hanash. The site is located nearby the borehole-spring "Bir Wahed" (29°07'19 " / 25°26'03"), about 15 km southwest of the Siwa Oasis.
 


2.)
Three extraordinary finds of debris in the GSS (dune corridors in the Silica-area) indicate that there are further structures like the Qarat-el-Hanash that are either eroded or covered by dunes.

 

Source: Bogumil Dec, on Youtube, 2016


3.) Three conspicuous breccias from the Gilf Kebir Crater Field (GKCF) in the eastern to southeastern direction

 

GKCF-01
23°14'37"N / 27°27'37"E

 GKCF-01
 

GKCF-05
23°32'42"N / 27°09'33"E