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A blind reverse fault can transfer displacement into folding above its buried tip. Look for an asymmetric growing anticline, often with a steep forelimb and gentler backlimb, aligned with the inferred fault strike. A fault-propagation fold is one possible geometry; the fold alone does not uniquely establish the fault's depth or shape. Exposed older geological strata may be more steeply tilted than younger deposits, while growth strata thin and onlap toward an uplifting crest or fan in dip as deformation accumulates. Progressive unconformities and warped young deposits help distinguish active folding from an inherited fold.

In the landscape, seek an elongate uplifted ridge, warped or tilted river terraces and alluvial fans, localized fold scarps, incision across the rising structure, and drainage deflection or abandoned channels. Compare landforms of known relative ages: increasing deformation with age records repeated motion. Opposite fold limbs may show contrasting uplift and tilting, while active axial surfaces can concentrate deformation into narrow belts even without the main fault reaching the surface. Combine geological mapping and dating with seismic reflection or evidence from geodesy where available; an erosional ridge alone is not proof of a buried active reverse fault.^[ref]

For a surface-breaking reverse earthquake, expect a fault scarp or disrupted belt with the hanging wall displaced upward and commonly over the footwall. Small thrust faults, splays and backthrusts may repeat or override shallow deposits. Shortened soil, roads or other markers may buckle, while soft sediment can form pressure ridges and compression folds. Near the scarp, gravitational collapse and local bending can also produce tensile fissures and small normal faults; a reverse event need not create compression everywhere at the surface.

For a blind reverse rupture, expect coherent uplift and warping, newly tilted surfaces, or a fold scarp without a throughgoing primary fault offset. Small flexural-slip surfaces along bedding, secondary thrust faults or backthrusts, and opening cracks or small normal faults over the bent outer arc of the anticline can accompany the folding. Deformation may be distributed or localized at fold hinges. Thus a blind main fault does not imply an entirely unbroken ground surface, and secondary cracking must be distinguished from the principal rupture by its geometry and displacement pattern. Shaking-triggered landslides or soil liquefaction can accompany either case and should not automatically be mapped as primary tectonic rupture.^[ref]