Brukkaros - how it was formed:
Following the final stages of the break up of
Gondwana there were
many places in Southern Africa where molten rock continued forcing its way up through the
earth's crust. It was about 80 million years ago, at the location of Brukkaros,
that one particular up-welling of magma found its way to the surface
blocked by one of the oldest rock formations in Africa, that of the Namaqualand
Metamorphic Complex. The enormous pressures being exerted resulted in
the earth's surface to bulge upwards causing a dome like mountain to be formed,
but the magma still did not break through. The upheaval the rocks were
subjected to would have resulted in extensive crack systems into
which the ground water would have seeped. The water in the deeper
fissures would have been under considerable pressure and would have
required to have been heated to a far higher temperature than 100°Celsius
before flashing off to form steam. The temperature of the
rock near to the magma would have been several hundred degrees and
at this depth would have caused the 'ground-water' to flash off as
superheated steam.
The Brukkaros Caldera measures about 2km across, a
considerable surface area, and it was in this vicinity that the rock
structure already being subjected to the up-welling pressures from
the magma that
were causing it to fracture would also have suffered the further aggravation of
the enormous series of energy forces from both hydrostatic shock
waves and ongoing expansion of pockets of superheated-steam. When
these pressures found release, massive amounts of overlaying rock
would have been blown into the atmosphere. having a similar effect
to that of a volcanic explosion, but without the issue of pumice or
lava-rock. Following this activity, the eventual collapse of the
dome resulted in the formation of a caldera, similar in appearance
to that of a "true volcano".
Hiking into the Brukkaros Caldera:
You
must carry enough water. Time - about 3-4 hours.
You need to be reasonably fit and have strong ankles
and knees as there is quite an amount of rock hopping involved. The
trail is not well developed and certainly should be avoided during
rains or following a downpour as the rock surfaces can become very
slippery. The wearing of a good pair of Hiking or Trail boots is recommended,
and preferably leather. A sprained ankle or fall would mean a long wait
and cause a considerable amount of problems for
the rescue team, and be expensive. There is no mobile phone reception
in this area.
