The Burnt Mountain on Farm Verbrandeberg. Not to be confused with the Brandberg Mountain that
lays some 50km south. It looks like an industrial slag
heap, and if you have seen the waste piles from any first world metal
foundry then this site will give you food for thought. The rocks that
you see exposed, did in fact burn, but what caused this 'colored 'ash heap' to be
placed so far away from 'big industry' ?
How The Rocks
Were Baked.
A long, long time ago when Namibia formed
part of the ancient and giant continent of
Gondwana
this particular area of Namibia was part of an inland lake rich in
marine life and vegetation. The dead organisms (plant and creatures) that drifted to the
bottom of the lake mixed-in with the silt. The countless years of wind
blown sands and dusts that settled in the lake grew into thick
sedimentary beds that covered the layers of decomposed organic material.
Namibia then experienced a long dry period. Many of the great inland
lakes dried-out and over the millions of years the winds blew in more sands
that covered the lake and its sedimentary layers to considerable depths. The
great weight of the overburden caused the sedimentary beds containing the
organic material to solidify into
shale. Time marched on and about
125 million years ago
Gondwana was experiencing the separation of was was to become
the African and South American continents. Many areas of Namibia and
particularly Damaraland experienced what is known as Karoo Volcanism.
Basaltic rock magma at temperatures in excess of 1000 Celsius pushed up
towards the earth's surface. It was at the site of the 'Ancient Lake'
where one particular up-thrust of the molten magma came into contact with
the 'organic material bearing shale' sandwiched between the layers of
sedimentary rock. The extreme heat ignited the organic material which
vaporized. The residual shale was literally baked resulting in a blackish
colored compacted rock. The shale contained particles of iron and manganese
that where later exposed to the atmosphere by ongoing erosion, oxidized
giving the purple shiny effect. The westward cliff-face is made up of clear
bands of sedimentary rocks that show a variety of reds, browns and creams
during the early morning and late afternoon sunlight.
The sedimentary rock formations at the Burnt Mountain are from the
oldest:
Tsarabis sandstone, Huab mudstone, Gai-As lacustrine
red mudstone, Etjo acolian sandstone.
Photographing the
Burnt Mountain:
Early in the morning, the low sun does allow for some
colorful photographs. Afternoon is also good, but don't leave it too
late as the western cliffs, being much higher, cast shadows over the
Burnt Mountain
Acknowledgements and
further reading: G1, G2, H12, P1
