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The mafic to felsic rocks at Yzerfontein form part of a composite 535 Ma post-orogenic pluton belonging to the Cape Granite Suite (CGS) of the Pan-African Saldania Belt of southwestern Africa. The pluton ranges from olivine gabbros (mostly at the northern end) to quartz monzonites, with monzonites the most abundant rock type. Minor felsic rocks in the form of quartz microsyenites and monzogranite occur more toward the southern end. The comparatively unaltered gabbro/monzonite has pyroxene δ18O values of 6.4‰, consistent with a mildly crustal-contaminated mantle-derived magma. Published εNd values of -1.9 to -0.3 similarly reflect crustal contamination of these mafic to intermediate rocks. The pluton is crosscut by extensive hydrothermal veining. Early quartz veining was followed by the precipitation of pyrite, calcite, tourmaline, jasper, epidote and a final stage involving the formation of barren quartz veins. The veins contain low-salinity (3 to 11 wt.% NaCl eq.), three phase (liquid + vapour ± opaques) fluid inclusions with total homogenisation temperatures of 125 to 320°C. The δ18O values of the quartz veins range from 9.8 to 14.7‰ and the fluid inclusion δD values range from -9 to -17‰. These ranges, together with the low salinities, are consistent with a meteoric origin for the vein fluids. Bulk-rock δ18O values range from 7.3 to 13.3‰ consistent with interaction of near surface fluids at temperatures of <300°C with the magmatic rocks. Open-space filling textures in quartz veins suggest vein formation in a hydrostatic regime. These, together with fluid inclusion isochores, suggest temperature-pressure conditions of no more than 170 to 300°C at ~0.5 kbar and no more than 1.6 kbar. The mineralised veins represent a shallow, poorly developed and possibly low-grade epithermal system. The mineralisation is likely related to drawdown of meteoric fluids during sub-solidus cooling of the dominantly intermediate pluton with little to no magmatic fluid influence. The mineralisation is poorly developed, possibly due to a lack of mixing between different fluid types. The various magmatic rocks, varying from mafic through dominantly intermediate to minor felsic, represents a minor mantle-derived mafic component of the Cape Granite Suite and likely related to the heat source that gave rise to voluminous crustal melting that generated the granitic magmas of the majority of the CGS. [ABSTRACT FROM AUTHOR]

• A continuum of Paleoproterozoic heritage, seen in Nd model ages, from N to S in the Bushmanland Domain (BD), with the Buffels River shear zone simply a regional discontinuity. • The southern BD (SBD) has a greater juvenile component than the northern BD (NBD), becoming more dominant post-1.10 Ga. • Orthogneisses derived from crustal magmas with subduction-influenced signatures with mixed Meso- to Paleoproterozoic model ages. The SBD Koperberg Suite derived from low degrees of melting of enriched SCLM, but at deeper levels than those of the NBD. • The paragneisses derived from largely reworked, mixed Meso- to Paleoproterozoic felsic to intermediate sources. • Paragneisses derived from largely reworked, mixed Meso- to Paleoproterozoic felsic to intermediate sources. • SBD Koperberg Suite derived from low degrees of melting of enriched SCLM, but at somewhat deeper levels than NBD Koperberg magmas. • D 2 deformation constrained to ~ 1.11-1.09 Ga, with peak M 3 metamorphism at ~ 1.05-1.02 Ga. The timing of tectonomagmatic events and petrogenesis of ortho- and paragneisses within the high-grade southern Bushmanland Domain (SBD) of the Namaqua Metamorphic Province is, largely, poorly constrained. U-Pb age dating and whole rock lithogeochemistry of the rocks of the upper granulite facies Kliprand dome provide constraints with regards to the evolution of the SBD during the 1.2–1.0 Ga Namaquan Orogeny. The SBD has a greater juvenile component, particularly added between ∼1.1 and 1.02 Ga, compared to the northern Bushmanland Domain (NBD). This is reflected in marginally younger T DM model ages (1.60–1.95 Ga) than for the NBD (∼1.9–2.4 Ga), and higher ε Nd(t) values for magmatic rocks, particularly for the late- to post-tectonic Spektakel Suite (SS), concentrated in the SBD. The ∼1.06 Ga Klein Lieslap Charnockite of the SS was derived from reworking of radiogenic Paleoproterozoic arc crust, but has a large juvenile depleted component compared to that of the ∼1.19 Ga Grootberg Gneiss of the syn-tectonic Little Namaqualand Suite. SBD mafic magmas were derived from low degrees of partial melting of subduction-influenced enriched subcontinental lithospheric mantle. The pre-tectonic ∼1.17 Ga Oorkraal Suite shows limited crustal contamination of mantle-derived melts. The post-tectonic ∼1.05 Ga Koperberg Suite was derived from deeper mantle melting than that in the NBD, but shows less crustal contamination. The supracrustal Kamiesberg Group was derived from mixed, reworked Meso- to Paleoproterozoic crust that showed a more dominant depleted component compared to that in the NBD. Incongruent anatexis of the paragneisses gave rise to crosscutting garnetiferous quartzofeldspathic segregations, notably the strongly peraluminous ∼1.07 Ga Ibequas Leucogranite. D 2 deformation, at ∼1.11–1.09 Ga, resulted in penetrative foliation. D 3 deformation, related to the development of a sub-vertical foliation in the limbs of F 2 folds, is constrained to ∼1.07–1.06 Ga, between emplacement of the Ibequas Leucogranite and the Koperberg Suite. Peak granulite facies M 3 metamorphism occurred at ∼1.05–1.02 Ga. These age constraints are similar to those of the NBD reflecting a synchronous tectonomagmatic and kinematic history. The SBD represents a deeper crustal level with a greater mantle influence than the NBD. [ABSTRACT FROM AUTHOR]

Scholarly and journalistic work on the critical state of leadership in Africa abound. Hellicy Ngambi (2011) attributes Africa's poor development, despite its wealth of diversity in natural and human resources, to leadership issues that need to be explored, considered and addressed. To confront the development challenges of a continent diverse in human and natural resources she proposes her principal and value-based, RARE (Responsible, Accountable, Relevant and Ethical) leadership model, as the most effective leadership approach. Popular perceptions suggest that, under the leadership of Jacob Zuma, the reality surrounding the leadership of many African countries has now also become the reality of South Africa. This article makes a distinction between 'leadership as influence' and 'leadership with character' - the latter embodied in the attributes of Ngambi's RARE leadership model. Ngambi recommends that further studies be conducted to explore the application of RARE leadership. Referring to the controversial Nkandla case, in which unlawful conduct and maladministration was found to have occurred in relation to the upgrades of Jacob Zuma's private residence; this paper explores the applicability of the RARE leadership model to an assessment of the leadership of South Africa's president. [ABSTRACT FROM AUTHOR]

Abstract: The Mesoproterozoic Bushmanland Group is situated in the central region of the 1000 to 1200 Ma Namaqualand Metamorphic Complex (NMC). The NMC comprises a belt of highly deformed medium- to high-grade metamorphic rocks to the west of the Archean Kaapvaal Craton of southern Africa. The Bushmanland Group, one of the many supracrustal sequences that make up the NMC, is a metavolcano-sedimentary succession that hosts economically significant concentrations of sillimanite and base-metal sulfide deposits. The present investigation was carried out to study the geochemistry of a large set of representative samples of psammo-pelitic schists from the Bushmanland Group, which includes data from three different schist units: Namies Schist Formation, Shaft Schist Formation and Ore Equivalent Schist. The objective was three-fold: to test the lateral correlatability of these schist units as determined by field relationships, to identify the geochemical signature of the schists and to test the validity of an Artificial Neural Network approach as an exploration tool. Two multidimensional datasets, respectively comprising 10 major and 18 trace elements, were constructed using selected published schist analyses. Both schist datasets were analyzed using self-organizing neural maps for visualizing and clustering high-dimensional geochemical data. Geochemical differences between the various schists were visualized using colored two-dimensional maps that can be visually and quantitatively interpreted. The results of this study confirm the lateral correlatability of the schist units evaluated in this communication. It was also found that each schist unit or portions of them represent a distinct geochemical signature that is related to true lithological variations. The results show that the Artificial Neural Network approach can be used as a powerful tool for regional mineral exploration in poly-deformed and metamorphosed terrains where identification of stratigraphic units through lateral correlation by means of fieldwork and petrography remains highly speculative. [Copyright &y& Elsevier]