Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) detrital zircon age data and detailed mapping of metasedimentary and metavolcanic pendants in the central Sierra Nevada are used to examine the age and origin of the metasediments, and to search for evidence of the location and history of the Cretaceous Mojave-Snow Lake fault. Quartzites from the Snow Lake, Benson Lake, May Lake, and Quartzite Peak pendants yield age spectra that best match Neoproterozoic to Ordovician passive-margin strata, thus supporting the presence of displaced passive-margin strata now preserved in Sierran pendants. Sediments at Cinko Lake, Strawberry Mine, and NE of Snow Lake are interpreted to be Early Jurassic to Early Cretaceous and marine, and probably not equivalents of the Fairview Valley Formation at Black Mountain as previously interpreted. Without this correlation, the suggested 400 km of displacement along the Mojave-Snow Lake fault is unconstrained, the exact location of origin for these passive-margin and Jurassic marine metasediments is uncertain, and the nature of the contact between these two sediment packages, which has been suggested to be an angular unconformity, is speculative and deserving of a more detailed evaluation. The timing of displacement along the inferred dextral Snow Lake fault is constrained to be between ca. 145 Ma, the maximum depositional age of Jurassic strata at Cinko Lake, and 102 Ma and 103-108 Ma, the age of the oldest intruding pluton and the youngest volcanic rocks juxtaposed along the stratigraphic break with adjacent eugeoclinal rocks.

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The Late Devonian South Mountain Batholith is a very large (7000 km2) composite peraluminous granitoid complex situated within the Meguma Terrane of the northern Appalachians. It is made up of two suites of granodioritic to leucogranitic plutons emplaced at approximately 380–370 Ma during the Acadian Orogeny, i.e. during the collision of Gondwana with the eastern margin of North America. A significant geophysical and geological database makes the South Mountain Batholith a type example of a very large syntectonic batholith emplaced within a collisional orogen. Gravity models reveal the plutons have flat or gently dipping floors at approximately 7.0 km depth and aspect ratios >6:1. They are underlain by deeper (>10 km) elongate northeast–southwest‐trending roots that may indicate magma feeder zones. Dyke transport of granitic magma and the progressive construction of plutons by sheet injections are supported by field observations and by mapping of the anisotropy of magnetic susceptibility at the pluton scale. The very narrow deformation aureole within the country rocks suggests lateral spreading of the plutons was not the main space creation mechanism during emplacement; space was mostly created by vertical displacements of country rocks. The data are consistent with a laccolithic model for syntectonic batholith assembly. The laccolithic plutons may have been emplaced at the base of the Meguma Supergroup metasedimentary rocks, suggesting a maximum thickness of approximately 7.0 km for the supracrustal rocks in the Meguma Terrane.