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The Fra Cristobal Range in south-central New Mexico exposes different styles of deformation variably affecting Precambrian crystalline rocks and Paleozoic, Mesozoic, and Cenozoic cover strata. Three main structural domains are recognized: I is a thick-skinned domain (basement-involved) along the northwest flank of the range; II is a thin-skinned domain along the southwest flank of the range; and III is a combined thick- and thin-skinned domain along the east flank of the range. Domains with thick-skinned deformation are characterized by fault-propagation folds cored by basement blocks bounded by reverse or thrust faults. These domains are segmented by transverse faults into two subdomain types: (1) east-vergent, overturned folds cored by a basement block with corners rounded by cataclastic flow; and (2) upright folds overthrust by basement that is imbricated by east-directed thrust faults. Thin-skinned deformation involves only Paleozoic cover strata and is characterized by decollement-style thrust faults, duplexes, and related upright to overturned folds. Assuming a balance of basement shortening along strike, it is likely that a basement uplift formed west of domain II but is now buried in the Rio Grande rift. Domain II structures developed either as thrusting propagated from basement into cover, by out-of-syncline thrusting east of the uplift, or by gravity sliding off the uplift. Domain III is characterized by a large, east-vergent, overturned monocline (probably basement cored at depth); the overturned limb was subsequently overthrust by its western subhorizontal limb (similar to a cross-crestal fold).

A two-stage development is suggested: (1) basement-cored fault-propagation folding in domain III, and (2) shortening in domains I and II to the west and late-stage cross-crestal faulting of the domain III fold. Behavior of basement rocks during deformation includes: (1) shortening and uplift of basement by reverse faulting, (2) cataclastic flow of basement on fault-block corners allowing folding of the basement-cover contact, (3) longitudinal segmentation of some domains by transverse faults, and (4) possible control of basement faulting by preexisting weaknesses.

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