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New isopach maps for four lower Paleozoic sedimentary successions (Bliss Sandstone-El Paso Formation, Montoya Formation, Fusselman Dolomite, and Devonian strata) in southern New Mexico indicate the presence of pronounced dextral deflections in the isopach patterns for these strata, particularly in data-rich areas near their northern pinchouts. These deflections occur across faults of known or suspected Laramide and, in the east, Ancestral Rocky Mountain ancestry. The magnitude and interpreted origin of the best-defined of these dextral deflections are: Hot Springs fault system near Truth or Consequences (-26 km, mostly Laramide); Engle Basin (32-36 km, mostly Laramide; includes-26 km value for Hot Springs fault system); Palomas Basin (57-60 km,-26 km of which is attributable to Laramide slip on the Hot Springs fault system: the remainder is of unknown origin); and the Tularosa Basin (-40 km, largely tectonic in origin but the reiative contributions of Laramide and Ancestral Rocky Mountain slip are unknown). Additional deflections may exist across the Pedernal uplift but are in need of further study.