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The Galice Formation is characterized by slaty cleavage, overturned tight-to-isoclinal folds having variable hingeline orientations, and a south–southeast-trending stretching lineation formed during the Nevadan orogeny. Calc-alkaline dikes and sills (151–146 Ma) that intruded the Galice Formation and its basement (Josephine ophiolite) are regionally metamorphosed, and some are deformed; however, some plutons of this age also overprint slaty cleavage, suggesting syntectonic intrusion. Amoeboid margins on some sills suggest intrusion began prior to lithification of the Galice Formation. Some dikes are intruded into pre-existing small thrust faults that predate the slaty cleavage. Dikes show a wide range of orientations, and poles to dikes are consistently oriented at a high angle to poles to extension veins and to the stretching lineation in the Galice Formation. Poles to dikes define two quadrants on an equal-area, lower-hemisphere projection separated by planes oriented at right angles. These planes are analogous to nodal planes of a fault-plane solution, and thus allow determination of P- and T-axes. Restoration of structures to their original (Nevadan) orientation results in the P- and T-axes, stretching lineations, poles to extension veins, poles to small syn-cleavage faults, and poles to cleavage all being essentially coplanar with the “movement plane” that strikes to the northwest and dips steeply. The “fault-plane solution” derived from dike orientations indicates northwest-southeast contraction, consistent with slip directions for most small faults having slickenfibers. A wide range of fold hingeline orientations and slip directions on small pre-cleavage faults, however, may record early west-directed shortening.

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