
Sorry for posting a photo of 2 juxtaposed slightly differently scaled, differently aged geologic maps in Portugese, but what can I do. The power was out at the DNG. Lorenço Marques was the Portugese name for Maputo.

Check out the purple/pink units along the western edge of the map - These are the Lebombo Volcanics. You can see that they continue both north and south into South Africa, where they have been studied. The Lebombo (or Lubombo) "Mountains" begin about 40km inland from Maputo. The highest ridge defines the borders between Mozambique-Swaziland. Geologists refer to this area as the Lebombo Monocline (means all the beds gently dip the same way) or the Lebombo Bimodal Volcanics - as the rocks here are either basalt or rhyolite. More on that later.
The second week was spent in the Nampula area - This Google Earth image shows the city of Nampula in the lower left (find the airstrip) and the outskirts to the east and north. Flat, flat land. 15-ft Ant Hills but Dad has never heard of this so he says there are not. And then there are... "inselbergs"... gneissic and granitic monoliths, looking like Half Dome (or Whole Dome), jutting every which way out of the landscape. Google Earth doesn't show them up so well, but there are many:

As you can see from the plane while descending into Nampula:

I'm getting carried away here so I'll quit - suffice to say that these provide tiny areas of perfect outcrop in an otherwise impermeable landscape - More on that later.
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