An east-west profile across the tilted Bergell pluton exposes a 10-km-thick interval in terms of crustal depth. Consequently, the floor as well as the root and “side” of the main intrusive body of the pluton crop out at the surface and a tentative three-dimensional geometry is constructed. At the highest crustal level, the geometry and deformation features at the margin of the pluton indicate ballooning, whereas the folded floor of the main intrusive body indicates synmagmatic shortening related to regional deformation. These contrasting features are best explained by shortening of the base of the pluton which caused an expansion at a higher crustal level. Final emplacement of the pluton into higher crustal levels was, therefore, not driven primarily by buoyancy, but rather by regional deformation within deeper levels of the crust.

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