Thicknesses of the late Proterozoic-Early Cambrian Arumbera Sandstone and Middle Cambrian Giles Creek Formation show initiation of growth of the Brumby anticline during the Middle Cambrian. Growth probably resulted from flowage of bedded salt in the late Proterozoic Bitter Springs Formation, possibly due to uneven deposition of fluvial sediments of the Arumbera. Such early growth structures are more likely to be oil prone than anticlines that formed later, during the Alice Springs orogeny (Late Devonian-Early Carboniferous), because adjacent source rocks were not buried as deeply. Positive source-rock analyses are known from several late Proterozoic units in the Northeast Amadeus basin.

Four major tectonic elements formed during the Alice Springs orogeny: (1) the N'Dahla nappe in the north, (2) the Phillipson nappe in the center, (3) tectonic windows (autochthon?) southward in the Phillipson nappe, and (4) the Camel Flat nappe in the south. Isopach maps drawn for each tectonic element suggest a minimum of 10 to 20 km of southward movement for each of the two northern nappes. A strike-slip fault along the east side of Todd River anticline, with 1 to 1.5 km of left-lateral offset, forms a prominent north-trending lineament across the dominant east-northeast trend of most of the folds in the Northeast Amadeus basin. It is paralleled on both sides by closed, doubly plunging anticlines. Major strike-slip faults and north-trending anticlines were not widely recognized prev ously in the Amadeus basin.

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