Sources and Effects of Fluids in Continental Retrograde Shear Zones: Insights from the Kuckaus Mylonite Zone, Namibia

Figure 1

Geological setting of the Kuckaus Mylonite Zone (KMZ) in the Namaqua Metamorphic Complex (NMC) of southern Africa (a). The KMZ is part of the Marshall Rocks-Pofadder shear zone system (MRPSZ), subparallel to the Southern Namaqua Front (SNF) and the Lord Hill - Excelsior Shear Zone (LHESZ) (b). In the study area, the KMZ is exposed over a 2 by 5 km area (shape of mapped area is a function of Quaternary sands coverage), with Tsirub Gneiss (TG) in the NE, the main leucogranite (LG) bodies in the middle, and biotite gneiss (BG) in the SW (c). Strain is heterogeneously distributed over 1-2 km (same strain gradient key as in Figure 2). Red boxes show locations of areas A-D in Figure 2.

(a)

(b)

(c)