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Figure 4: Graph illustrating the average monthly rainfall and maximum and minimum temperatures for the Letaba RanchNature Reserve (Masalale Pack House Weather Station: Latitude: 23.7004°S; 30.7888°E; 375 m above sea level).2.4.3 TopographyThe topography of the LRNR consists of gently undulating landscapes located at altitudes of between340 and 400 m above sea level, with the occasional hill located at altitudes of up to 450 m above sealevel (Figure 3). The most distinct topographical feature of the LRNR is a number of koppies located inthe central zone of the southern section of the reserve, collectively known as Sable Mountain. Thehighest koppie, Middelkop, is located at an altitude of 446 m above sea level (Figure 3).Undulating landscapes comprise approximately 88% of the surface area of the reserve, with 2% of thearea characterised by granite koppies. The remaining 10 % of the surface area of the reserve consists ofdry drainage lines that drain towards the perennial Letaba River.2.4.4 Geology and Soils2.4.4.1 GeologyA variety of geological formations occurs in the LRNR and can generally be grouped according to thevegetation unit it supports.The geology on which Granite Lowveld occurs, ranges from Archaean granite and gneiss, SwazianGoudplaats Gneiss, Makhutswi Gneiss and Nelspruit Suite to the younger Mpuluzi Granite.Lowveld Rugged Mopaneveld geology is mostly underlain by Goudplaats Gneiss and Makhutswi Gneiss,with some ultramafic metavolcanics (rocks rich in chlorite, amphibole, talc and serpentine) andmetasediments of the Giyani Greenstone Belt (all Swazian Erathem).Phalaborwa-Timbavati Mopaneveld geology consists of quartz-feldspar rocks of the Makhutswi Gneiss(Swazian) dominate, intruded by the Lekkersmaak Granite (Randian).Tsende Mopaneveld geology includes quartz-feldspar rocks (Goudplaats Gneiss Basement), which arelow in potassium.Reserve Management Documents: Letaba Ranch Nature Reserve (Strategic Plan) 27