Kalahari Craton

These arguments can be refined. In Appendix B, we calculate the mantle heat flow as a function of lithosphere thickness and show how it depends on the surface heat flow. Pressure and temperature estimates from mantle xenoliths may be combined to determine a best-fit geotherm consistent with heat transport by conduction. Mantle heat flow estimates obtained in this manner are in the following ranges 7-15 mW beneath the Fennoscandian Shield (Kukkonen and Peltonen, 1999), 17-25 mwm for the Kalahari craton. South Africa (Rudnick and Nyblade, 1999), and... 

The Kalahari Craton of southern Africa, consisting of the Kaapvaal and Zimbabwe Cratons and the Limpopo Mobile Belt, has formed a stable unit for the past 2.3 Ga (McElhinny ... 

James Pouch (2002) showed intermediate period fundamental mode Rayleigh wave phase and group velocity data measured across the Kalahari Craton and a shear-wave velocity model from inversion of these data. They find evidence for a weak low-velocity zone below 120-130 km depth. The phase velocity data of James Pouch (2002) are not significantly different from the Rayleigh wave phase velocity measured by Priestley (1999). However, such intermediate period fundamental mode dispersion data do not provide stringent constraints on mantle velocities below c. 200 km depth. 

Recent global tomographic models (Ritsema van Heijst 2000) include intermediate-frequency surface-wave data. These models show the high shear-wave velocities extending to no more than 200 km depth beneath the Kalahari Craton with PREM-like velocities below 200 km depth, consistent with the model shown in Figure 2. 

Unit IV). These basement rocks were over-ridden by the Mt Wegener nappe (Unit III, south), which was itself partly coveted by a slice of rocks (Unit III, north), which included an ophiolite (Unit II). The northern Shackleton Range is composed of remohUized basement rocks derived from the Kalahari craton of southern Africa (Unit I) (Adapted from Tessensohn et al 1999a)... 

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