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How do nappes show the folding and thrusting of rocks in the Outer Carpathians?

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Carpathian Mountains; cross section of the Western Carpathians — Carpathian Mountains Regional division of the Carpathian Mountains (top) and a geologic cross section of the Western Carpathians (bottom). The location of the cross section is shown by the line N–S on the map.

In the Outer Carpathians, nappes serve as evidence of intense tectonic activity, representing vast masses of rock that have been folded and thrust over one another. These structural units demonstrate the region's complex geologic history, where large sheets of rock were displaced by significant distances from their original positions through folding or low-angle thrust faulting.12

This process effectively positions older rock layers over younger ones. In the Outer Carpathians, these nappes are composed primarily of flysch and include major units such as the Skole, Silesian, and Magura nappes. The presence of these structures highlights the mountain-building movements that characterized the region's development, where the compression of the Earth's crust forced these massive rock sheets to stack and overlap, creating the parallel structural ranges observed today.213