Located in an area of Upper Karoo sandstones in the Rufunsa Rift, which is in the mid-Zambezi-Luangwa rift zone, the Kaluwe occurrence forms a crescentic outcrop nearly 10 km in length.
You are here
The Nachomba carbonatite forms an isolated hill a little less than 100 m high, 8 km southeast of Kaluwe (No. 180-00-006). It lies in the Uma depression surrounded by lateritic soils that obscure outer contacts.
The Mwambuto Hills form a ring, approximately 5 km in diameter, of domed metasomatised Karoo mudstones, inside which is a ring of feldspathic breccias. The 1.5 km diameter core of the complex forms a depression and is composed of volcanic and intrusive carbonatites.
Chasweta is an eroded volcano with two principal vents indicated by shallow depressions. There are numerous satellite vents around the complex and the remnants of the products of these vents are widespread to the north.
The Mkwisi limestone is described by Bailey (1961) as intruding a series of late Precambrian metasediments. It is associated with a breccia which consists of country rock fragments in a calcite cement.
This limestone, like that of Mkwisi (No. 180-00-010), was thought to be carbonatitic by Bailey (1961), but mobilised sedimentary limestone by Cairney (1964). Keshya is much larger than Mkwisi (No. 180-00-010) and forms a substantial intrusion cutting sub-Katangan basement. Bailey (pers.
Matheson (1967) refers to limestones southeast of Kabanga as appearing to have been formed by the intrusion of a carbonatite magma. They are described as irregular bodies, banded in places, within granulitic gneisses and, as is clear from Matheson's map, are substantial bodies.
A range of alkaline rocks from probable peralkaline granites to foid syenites are described by Murray-Hughes and Fitch (1929), but this was a reconnaissance study and little detail is available.
This is an apparent Mesozoic carbonatite occurrence that is located some 6.5 km west-northwest of the Marindagomo trigonometrical Station northeast of Kariba. It is reported to lie within Karoo strata at the foot of the Zambezi Escarpment and is largely concealed by more recent sediments.
The Sadiman volcano is younger than Lemagrut the products of which it overlaps. It is made up largely of nephelinitic tuffs and agglomerates. Subsidiary lavas include nephelinite, phonolitic nephelinite, melilite nephelinite, phonolitic trachyte and sodalite phonolite.