2015 GSA Annual Meeting in Baltimore, Maryland, USA (1-4 November 2015)

Paper No. 152-7
Presentation Time: 3:00 PM

GETTING TO KNOW THE DIMENSION STONES OF MALAWI: A HERITAGE CONCERN


KAMANGA, Tamara Faith, Geological Survey Department of Malawi, P.O Box 27, Zomba, Malawi, tamarakamanga@gmail.com

The geology of Malawi is grouped into four main lithological units that is the Basement Complex, Karoo super group, Chilwa alkaline province and the Tertiary to Quaternary sedimentary deposits. The rocks of the Basement Complex cover 80% of the country and range in age from late Precambrian to early Paleozoic. The basement rocks comprise gneiss, granulite and schist with associated mafic, ultramafic, syenite and granite rocks.

Malawi is endowed with different types of dimension stone deposits most of which remain unexploited and explored. Some of these have been preserved as World Heritage sites by UNESCO.

In Northern Malawi, there are several granite deposits including the Nyika, which is the largest single outcrop occupying approximately 260.5 km2, Mtwalo Amazonite an opaque to translucent bluish-green variety of microcline feldspar that occurs in alkali granites and pegmatite, the Ilomba granite (sodalite) occuring in small areas within biotite; apatite, plagioclase and calcite. In the Center, there are the Dzalanyama granites, Chongoni and the Sani granites. In the South, there are the Mangochi granites.

Dolerite and gabbroic rocks spread across the country, treading as black granites. Malawi is also endowed with many deposits of marble. A variety of other igneous, metamorphic and sedimentary rocks are also used as dimension stones.

The major application of dimension stone is within the construction sector, which accounts for over 80% of consumption, with the memorial monumental industry accounting for 10%, and various special applications for around 3%.

In ancient times stone was used for building, decorative purposes and as a medium with the spirit world. This is evident today with ancient stone buildings still standing, and stone carvings found on stones, some of which have been preserved as cultural heritage sites. Ancient artists drew for inspiration on traditional culture, the mythology, folklore, rituals and beliefs in ancestral spirits that remain strong strands even in contemporary, urban Malawian life.

Discovery of more dimension stone deposits through research is essential to minimize forex lose and increase the social- economic growth through exports as well as to preserve the stone heritage of the country.