Vol. 65. 



KARROO SYSTEM IN NORTHERN RHODESIA. 



421 



The open character of the Intanga Valley and the high altitude 

 at which the Karroo beds occur lead me to suspect a rising synclinal 

 fold similar to the Muchinda, the limbs and head of which have 

 been removed by erosion. 



I have not traversed the Kafue gorge, but can recognize that 

 it presents evidence of the radical change which is overtaking the 

 drainage-system of the plateau. Above the railway-bridge (altitude 

 3205 feet) it meanders placidly over flats that seem to have no 

 perceptible variations of level ; but a few miles below it commences 

 a rapid descent of the Zambesi 'trench', and falls 1755 feet in 

 20 miles. 



III. The Karroo System. 



I may now proceed to describe the rocks that build up the 

 regions of the Karroo System in Northern Rhodesia, giving, first, a 

 table of correlation based on investigations south of the Zambesi. 

 Fossils found in these localities point to the Permo- Carboniferous 

 age of the deposits, and include them in the Karroo System of 

 South Africa. In the absence of discoveries of fossils from many 

 beds, and, as the succession is conformable, the grouping has to be 

 founded on lithological features or general relationship. The de- 

 marcation cannot, therefore, always be precisely defined. 



Silicified wood in fragments, or in prostrate trunks as long as 

 9 feet, is found in all beds up to the Forest Sandstone. It would 

 be interesting if specimens from the various horizons were carefully 

 investigated, for they might be found to possess distinctions such 

 as would give a key to the zonal stratigraphy of these regions, and 

 one more reliable than lithological characters. 



Gape Colony. 



Trans 



vaal. 



Rhodesia. 



Karroo. 



Karroo. 





Karroo. 



Storm- [ 7olcanio Bec1s - 

 ° ' \ Cave Sandstone. 



Volcanic Sei 



•ies. 



Volcanic Series (Batoka 







Basalts, Tuli Lavas, etc.). 



Bushveld Sandstone. 



Eorest Sandstones (and 









Samkoto Sandstones). 1 



Beaufort. 







Escarpment Grits and 

 Upper Matobola Beds. 



Ecca. 



Ecca. 





Lower Matobola Beds (and 

 Coal Series). 



Dwyka. 



Dwyka. 





Basal Beds and Boulder- 

 Conglomerates. 



1 It will be seen that the position assigned to the Samkoto Beds, in my paper 

 of 1903, is here altered, while the Sijarira Quartzites are left out, owing to tbe 

 doubt as to their horizon since Mr. Lamplugh investigated the Deka Fault, 

 Quart. Journ. Geol. Soc. vol. lxii (1907) p. 162. 



Q. J. G. S. No. 259. 



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