= Solution
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.<Blind-thrust mapping report by United States Geological Survey>[Active fold scarps can arise through localized coseismic uplift and tilting without the principal thrust reaching the ground surface.]{ref}
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