Wadi Allaqi regional
overview
Gippsland has the right to explore nine tenement areas located in the Wadi Allaqi region of South-eastern Egypt. Eight of the areas contain historical gold workings with the ninth containing a copper-nickel deposit
The Wadi Allaqi region is located to the southeast of Aswan in the south-western part of the Eastern Desert of Egypt covering an area of about 12,000km2. The area, which is bounded to the west by Lake Nasser and to the east by the Red Sea is accessible via an asphalt road from Aswan located to the northwest. Elsewhere access is available by 4-wheel drive vehicles along the wadis.
Egypt has a long history of gold mining with the earliest references to gold mining in the pre-4,000 BC period. It is estimated that up to 3,000t of gold could have been mined by the Pharaohs from lands held under their control. Within the Wadi Allaqi region the earliest reference to mining is the Twelfth Dynasty of the Middle Kingdom (1991-1786 BC) when the area was known as the region of Akita in the Land of Wawat. Mining probably continued in episodes during the Pharaonic period. Further mining took place during the Roman era from 181 BC to 5 AD and then again during Islamic times from the ninth century up until the fourteenth century. In the early 1900s the area was explored and mined by British and South African companies, principally the Nile Valley Company Ltd at Um Garayat and Haimur, through to the 1920s. Some small time mining continued through to the early 1950s.
The ancient historical mining was focused entirely on the near-surface high grade quartz veins and alluvial gold. Evidence of the historical mining activity is clearly seen in stoped out quartz veins at shallow depths by means of shafts and adits and the presence of numerous stone tools used in crushing the gold ore. Waste dumps and tailing are present at a number of these deposits indicating that they were sites of significant mining activity by the ancients.
Apart from limited regional exploration during the 1960s and 70s under the auspices of the United Nations there has been no significant exploration or mining since the early 1950s when Egypt became a republic.
The nine Wadi Allaqi prospects, each 16km2 in area, include:
| Gold |
Copper-nickel |
| Um Garayat |
Um Garayat regional |
Abu Swayel |
| Nile Valley Block A |
Nile Valley Block E |
|
| Seiga |
Um Tiur |
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| Haimur |
Um Shashoba |
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Geology
The geology of the Wadi Allaqi region comprises the most southerly segment of the late Precambrian Arabian Shield within Egypt. It contains a northwest and west-trending thrust belt of metasedimentary and metavolcanics schist, ophiolitic nappes and gabbro/granite complexes which are unconformably overlain by Nubia Group sandstones of upper Cretaceous age. Metasedimentary units are interleaved with serpentinite-talc nappes, which propagate through the volcanics/volcaniclastic units. The ophiolitic serpentinites are tectonically altered
to ankerite-silica-talc magnesian schist and calcite-brucite marbles along the strike. These lower to upper greenschist facies assemblages are intruded by a suite of magmatic and subvolcanic units ranging from layered ultramafic-mafic sills to gabbro-tonalite-granodiorite- monzogranite-felsite-rhyolite plutons. A swarm of basic and intermediate dykes infill tensional fractures in the oval shaped post-tectonic granites. Occurrences of trachyte and syenite plugs and trachytic pipes are located in the region and are possibly of Cretaceous age. Generally, the area is mainly built up of two folded volcanic belts separated by ophiolitic tectonic mélange belt.
Gold mineralisation
Wadi Allaqi district contains a number gold occurrences and deposits. The gold mineralisation occurs within quartz veins and veinlets within brittle-ductile shear zones concordant with the general northwest tectonic trend in the area. The steep dip of the veins and the hardness of the host rocks presented technical mining challenges to the ancients. The exposed parts of the veins were easily removed but continued exploitation required going underground. This was done in one of two ways; either by following the shoot down plunge or by digging an adit below the level of the vein intersecting the vein at different levels. The ancients panned powdered quartz samples taken from the vein to identify the ore zones.
Nickel-Copper Mineralisation
Copper at Abu Swayel was mined by the ancient Egyptians during the Twelfth Dynasty of the Middle Kingdom (1991-1786 BC) from shallow open cut workings which can be traced over a length of 180m.
The mineralised host unit is an elongated, lenticular amphibolite body which can be traced for some 500m along a northwest-southeast strike and enclosed by a garnet-mica schist. Copper-nickel mineralisation occurs both in the amphibolite body and in enclosing host. The mineralisation contains chalcopyrite, pyrite, nickel-bearing violarite, and ilmenite. The relict textures of the pyrite and the violarite show the primary ores to be pyrrhotite, pentlandite and chalcopyrite. The drilling intersected a persistent, apparently stratiform, sulphide-bearing zone of variable thickness, that hosts the mineralised amphibolite body.
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