This talk will be presented by Matthys A. Dippenaar, and will run through the stratigraphy and examples of South African gneisses and, to a lesser extent, granites. These rocks underlie very large and developed portions of South Africa. They are referred to as basement granites in places, and should be understood in lithostratigraphic context and distribution by geologists and geoscientists. This will also benefit people working with geology and requiring a better understanding of these rocks.

The focus on the talk will be specifically on the engineering geology, hydrogeology, and vadose zone hydrology. Geology determines what fieldwork is conducted, and what data is required. Development and agriculture require investigation of these lithostratigraphic units within different climatic domains that result in different weathering products that will have different geotechnical properties and problems.

The lecture will be presented in person in Mineral Sciences Building Room 4-22 and online via Zoom (information below) Wednesday 5 November 2025 from 15:00 until 16:00. Information and requesting of details are available at https://forms.gle/4HRWqQJP8G1MNZ2P7 to ensure that your details are on record and that your participation can be verified.

Makhutswi Gneiss (Photograph by Matthys Dippenaar, June 2025, Limpopo Province)

Matthys A. Dippenaar is inviting you to a scheduled Zoom meeting. Join Zoom Meeting: https://up-ac-za.zoom.us/j/92097125477?pwd=blxGuARvizSk8Fhl8asQoxXN8Q3WaG.1

Meeting ID: 920 9712 5477; Passcode: 430619