Komatiitic greenstones were first recognised in South Australia from drillcore at Lake Harris on the Gawler Craton by Mines and Energy SA personnel in 1991. Subsequent petrography and detailed aeromagnetic data interpretation led to targeted drilling by PIRSA's Geological Survey Branch in 2001 and 2002. That drilling aimed to confirm the greenstone strike continuity, define stratigraphy and contact relationships, elucidate details of the lava flows, establish the depth of cover, and identify the regolith assemblages, geochemistry and landscape evolution of the targeted areas. Over 130 aircore holes were drilled into regolith, unweathered greenstone and quartzo-feldspathic basement. Eleven of these holes had additional diamond core tails, and significant diamond core into fresh basement was retrieved from another eight earlier-drilled exploratory holes. This regolith study was run in parallel with the 2001-2002 basement drilling programs, and used a selection of the available aircore samples, augmented by an additional three fully cored regolith profiles drilled in mid-2002. These provided control on the earlier aircore chip logging, and more detail of weathering and related geochemical dispersion. Together, these projects have provided significant new information for key sections of the Harris Greenstone Belt. Aircore drill cuttings provided a good orientation sample set within the weathered greenstone terrain. Later on, drill cuttings and core required revisiting and reinterpretation when assay, petrographic and other results became available. As the drill core dried out, some subtle regolith features became more apparent. Erosion of the deeply weathered greenstone has produced, in at least one area, a mass wasting or landslip of a surface to form a debris flow deposit (>5 m thick) with remarkably similar properties to its source. Ferruginous cappings on the Harris Greenstone Belt are very thin (<1 m) or have been removed by erosion. Greenstone spinifex textures in the serpentinised komatiite are preserved in saprolite at Lake Harris to within 17 m of the surface and to within about 2.5 m of the main unconformity (transported on in situ). Bioturbation of greenstone-derived ferruginous resistate materials may provide a supplementary exploration sample medium and may make it possible to 'see through' 5-10 m of transported cover. Soil sampling has revealed that komatiite indicator elements (Mg, Cr, Ni, As, Co, Fe, Mn and V) are elevated over exposed weathered greenstone or where that lithology is mantled by very thin cover. Mineralisation-related elements (Au, Bi, Cu, Pb and W) are elevated there too, indicating prospective ground for base metals. Detailed regolith mapping at prospect or 1:10,000 scale can provide an 'outcrop versus transported cover' framework to better target surficial geochemical sampling. It can also lead to landscape evolution models that may provide vectors to dispersed mineral signatures or from those towards concealed mineralisation. These findings should prove useful, as there has not previously been any similar study done over greenstones in South Australia.