The Six Mile Hill area was one of three areas targeted in the Minerals Systems Drilling Program (MSDP) during 2015-2016. Four holes were drilled in the Six Mile Hill area to test for potential for iron oxide-copper-gold (IOCG) mineralisation and to gain a clearer understanding of the stratigraphy of the lower Gawler Range Volcanics (GRV) at its exposed south-eastern margin. Three of these holes intersected the lower GRV sequence: MSDP01, MSDO03 and MSDP04. This report summarises the GRV sequence which they and Myall Creek RC1, an earlier drilled hole in the Six Mile Hill area, have encountered, then suggests correlations of individual units between these drillholes, and lastly provides an interpretation of the depositional setting of the GRV sequence in the Six Mile Hill area. MSDP01 was drilled to 1116.8 m depth and intersected six units from the lower part of the Mesoproterozoic Gawler Range Volcanics, comprising an ‘upper felsic volcanic unit’ (30.5-66.46 m), an ‘upper mafic volcanic unit’ (66.46-368.97 m), a ‘middle felsic volcanic unit’ (368.97-665.15 m), a ‘lower mafic volcanic unit’ (665.15-964.2 m), a ‘quartz- and feldsparphyric felsic unit’ (964.2-1095.95 m), and a lower felsic volcanic unit’ (1095-1116.8 m). MSDP03 was drilled to 262.6 m depth and intersected two units from the lower part of the Mesoproterozoic Gawler Range Volcanics, comprising a ‘felsic volcanic unit’ (10.3-102.2 m), and a ‘mafic volcanic unit’ (102.2-262.6 m). MSDP04 was drilled to 843.9 m depth and intersected two units from the lower part of the Mesoproterozoic Gawler Range Volcanics, comprising an ‘upper felsic volcanic unit’ (5.0-89.7 m), and a ‘mafic unit’ (89.7-437.2 m) intruded by a ‘flow-banded felsic unit’ between 264.95-340.0 m. Myall Creek RC1 was drilled to 551.34 m and intersected an ‘upper felsic volcanic unit’ (0-44.1 m), an ‘mafic volcanic unit’ (44.1-89.1 m), a ‘quartz- and feldspar-phyric rhyolite unit’ (89.1-~182 m), overlying a succession of rhyolitic to dacitic volcanic units (~182-551.34 m). Proposed correlations between the four drillholes are based on features including phenocryst composition and abundance, some textural characteristics for the felsic volcanic units, and groups of compositionally/texturally distinct basalt flow units and intercalated sedimentary horizons for the mafic volcanic units. The ‘felsic volcanic unit’ and ‘mafic volcanic unit’ in drillholes MSDP03 and RC1 are correlated with the ‘middle felsic volcanic unit’ and ‘lower mafic volcanic unit’ in MSDP01. This interpretation implies post-emplacement fault movement on the order of 550 m to account for this difference in preservation level between drillholes. The two occurrences of mafic volcanic rocks in MSDP04 are interpreted to be part of a single mafic volcanic unit that was intruded by a felsic sill, and are correlated with the ‘upper mafic volcanic unit’ in MSDP01. The mafic volcanic units consist of thick sequences (to ~300 m) mainly composed of stacked basalt flow units, which are characterised by amygdaloidal and in places brecciated tops, denser massive interiors and, in some cases, brecciated bases. The occurrence of hyaloclastite intervals, probable pillow texture and rare peperite, indicate emplacement of some flows or parts of flows in a subaqueous setting. The interpreted environment is a basin in which rivers were periodically dammed to form relatively large fresh water lakes. The nature and position of source vents for the basalt flows are unknown, but given the thickness and known extent of these rocks, the sources are considered most likely to be fissures or shield volcanoes. The felsic volcanic units are mainly thick, compositionally and texturally relatively homogeneous, and have been interpreted as predominantly coherent. Some of them retain flow-banding or weak flow alignment of platy minerals, as well as narrow, finely amygdaloidal and/or breccia zones, mainly near the base, and also have minor occurrences of peperitic mixing between included rafts of fine sediment and the host, the latter indicating that basalt and felsic magmatism were essentially synchronous.