Field investigations in North Victoria Land, Antarctica during GANOVEX IX (2005/2006) allow the revision of the Triassic-Jurassic stratigraphy of ~300 m thick continental deposits in between the crystalline basement and the Kirkpatrick lava flows of the Ferrar Group. The lower stratigraphic unit (Section Peak Formation) is characterised by braided river-type quartzose sandstone deposits with intercalations of shale and coal occurring at the top. It is overlain by a homogeneous unit of reworked tuffs composed of fine-grained silicic shards, quartz and feldspar (new name: "Shafer Peak Formation"). These deposits can be correlated with parts of the Hanson Formation in the Central Transantarctic Mountains and require a distal yet unknown source of massive silicic volcanism. Clastic products of mafic volcanic eruptions, formerly described as a separate stratigraphic formation (Exposure Hill Formation), occur within local diatreme structures as well as intercalated at various stratigraphic levels within the sedimentary succession. These dominantly hydroclastic eruptions are the first subaerial expression of Ferrar magmatism. The initial Kirkpatrick lavas/pillow lavas were generated from local eruptive centres and again may be overlain by thin sediments, which are covered by the thick plateau lava succession known throughout the Transantarctic Mountain Range.

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Field data gathered during GANOVEX IX (2005/2006) in Northern Victoria Land, Antarctica, indicate that volcaniclastic deposits of phreatomagmatic eruptions (so-called Exposure Hill Type events) are intercalated with fluvial deposits of Triassic-Jurassic age at two stratigraphic levels. Abundant scoriaceous spatter (locally welded) indicates a hawaiian/strombolian component. Breccia-filled diatremes, from which volcaniclastic deposits were sourced, are rooted in sills which intruded wet sediments. The deposits are thus subaerial expressions of initial Ferrar magmatism involving intrusion of multiple shallow-level sills. Due to magma-sediment interaction abundant clastic dikes are developed that intrude the sediments and sills. All igneous components in the volcaniclastic deposits are andesitic in composition, as are the chilled margins of the sills. They are more differentiated than the basaltic andesites of the younger effusive section of Kirkpatrick plateau lavas which in northern Victoria Land start with pillow lavas and small volume lava flows from volcanic necks.

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