Mélanges represent a significant part of the Miocene Nabae accretionary complex. Such mélanges show sheath folds with D1 axial plane pressure-solution cleavage, whereas the coherent unit shows asymmetric folding with D1 slaty cleavage. In addition, the mélanges are characterized by D1 asymmetric shearing, which includes both thrust and right-lateral-sense components, in contrast to D1 pure shear that characterizes the coherent unit. Thus, this tectonic style acted on the climax of prism development can be referred to as a tectonic mélange. However, because the D1 shear displacement is almost negligible, D0 normal faults and basaltic dikes, operated when matrix sediments were not consolidated, are not disrupted. Oceanic materials such as basalt and chert cannot be incorporated into terrigenous matrix, given the small displacement associated with the D1 shearing. Exotic blocks of chert and sandstone show D minus 1 (D–1) cleavage, which is apparent in the older, probably Eocene, accretionary prism. When this prism was exhumed, it supplied debris to the Miocene trench, and then underwent additional D1 deformation, which included the above asymmetric shearing. This sedimentary and two-way-street tectonic process was recycled within the prism as the latter developed. Thus, as the block-in-matrix fabric was originally sedimentary and labeled D0, the tectonic mélange process that forms block-in-matrix fabric is only conjectural for the Nabae complex. Also it is suggested that these deformations are not progressive nor distinctive for each other.

Integrated geological studies in the Central Zone of the Limpopo Complex formed the basis for the construction of a composite deformation (D)–pressure (P)– temperature (T)–time (t) (D-P-T-t) diagram that shows the following: First, in the Neoarchean the Central Zone probably underwent high-pressure (HP) (P >14 kbar, T ~950 °C) conditions followed by near isothermal decompression to ultrahigh- temperature conditions (UHT) (T ~1000 °C, P ~10 kbar), before ca. 2.68 Ga. Second, the post-peak exhumation history linked to two distinct decompression cooling stages commenced at ca. 2.68 Ga and ended before the emplacement of the Bulai Pluton at ca. 2.61 Ga. Stage 1 started at P ~9 kbar, T = 900 °C, and culminated with the emplacement of leucocratic anatectic granitoids at ca. 2.65 Ga. Stage 2, linked to the development of major SW-plunging sheath folds and related shear zones, started at P ~6 kbar, T ~700 °C and ended at P ~5 kbar, T ~550 °C, before ca. 2.61 Ga. The rocks resided at the mid-crustal level for more than 600 m.y. before they were again reworked at ca. 2.02 Ga by a Paleoproterozoic event. This event commenced with isobaric (P ~5 kbar) reheating (T ~150 °C) of the rocks related to the emplacement at ca. 2.05 Ga of magma linked to the Bushveld Igneous Complex. This was followed by final exhumation of the Central Zone. The Neoarchean high-grade event that affected the Limpopo Complex is linked to a Himalayan-type collision of the Kaapvaal and Zimbabwe Cratons that resulted in over-thickened unstable crust and the establishment of HP and UHT conditions. This unstable crust initially responded to the compressional event by thrust-driven uplift and spreading of the marginal zones onto the two adjacent granite-greenstone cratons. The post-peak exhumation history was probably driven by a doming-diapiric mechanism (gravitational redistribution).