Folded Strata Valley

Folded Strata Valley is an original illustration set in Zagros Foothills, Iran. It lies in the subtropics, where the climate is hot semi-arid steppe.

Alternating pale and dark rock layers bend into a giant arch across a bare ridge, the strata continuing coherently right through the fold. A dry braided gravel channel runs along the valley floor. Sparse pistachio scrub clings to the slopes, and nothing softens the geology.

Why does solid rock fold instead of snapping?

Rock only folds like that when it is squeezed slowly while buried deep enough to bend rather than snap — the signature of two continental plates colliding. That the layers stay continuous through the arch shows the deformation, not erosion, made the shape. The braided dry channel means water arrives seasonally and violently. Bare slopes with scattered drought-hardy scrub place it in a hot semi-arid belt.

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