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The central feature of the range, as worked out by Mr. Tolman, is a great post-Carboniferous intrusive mass of siliceous muscovite granite modified to a gneissic rock near its margins, surrounded by an intense contact metamorphism in which rocks of widely different kinds have been conspicuously affected. The oldest rock cut by this granite is a coarse biotite granite which apparently as a result of the later granitic intrusion, grades into augen gneiss, and locally this rock in turn has been transformed into a thinly fissile schist. ABSTRACTRecent field work and accumulated Rb-Sr studies, when combined with previous U-Th-Pb and K-Ar investigations, allow a new synthesis of the crystalline terrane within the Santa Catalina-Rincon-Tortolita crystalline complex. When all the available data are integrated, it is apparent that the crystalline core is mainly a composite batholith that has been deformed by variable amounts of cataclasis. The batholith was formed by three episodes of geologically, mineralogically, geochemically, and geochronologically distinct plutons. The first episode (75 to 60 m.y. B.P.) consisted of at least two 217 on June 19, 2015 memoirs.gsapubs.org Downloaded from of these events is clearly constrained to the Catalina intrusive episode because it formed during or after the emplacement of Tortolita quartz monzonite (about 27 m.y. B.P.) but before the intrusion of postfoliation dikes (about 24 m.y. B.P.). All three episodes of mylonitization contain the distinctive and much discussed east-northeast-trending lineations. All events of mylonitization are constrained to a 50-m.y. interval of time from 70 to 20 m.y. ago. Although continuous mylonitization from 70 to 20 m.y. ago cannot be unequivocally disproved, the strong association of mylonitization with the three plutonic episodes suggests that deformation in the Santa Catalina-Rincon-Tortolita crystalline core, like intrusion, was episodic. on June 19, 2015 memoirs.gsapubs.org Downloaded from NviyaiAivoaud A / \ t S f J tu V oo > e 1

The Kupferschiefer is a copper-, polymetallic-, hydrocarbon-bearing black shale of the lowermost Zechstein Group of Permo-Triassic age (252 Ma) in Germany and Poland. It is usually 1 m thick and underlies 600,000 km 2 , extending from Great Britain to Belarus for a distance of over 1500 km. At a district scale, copper has been mined for over 800 years since its discovery circa 1200 A.D. Mineralogical, chemical, and geological analyses of the combined Zechstein-Kupferschiefer show strong chemical and paragenetic relationships between the Zechstein salines, Kupferschiefer, and Weissliegend sandstones that lead to a broader, more unified, genetically linked model related to deep-sourced, hot, hydrothermal, mud-brine volcanism. The overall Zechstein-Kupferschiefer chemical stratigraphy suggests density-/composition-driven fractionation of deep-sourced, metal-rich, alkalirich, silica-aluminum-rich, halogen-rich, high-density brines. The ultimate brine source is interpreted to be serpentinized peridotite in the lower crust near the Moho transition to the mantle. Dehydration of the serpentinite source to talc (steatization) by mantle heat during failed, intra-continental rifting of the Pangaea supercontinent at the end of Permian time released vast amounts of element-laden, high-density brines into deep-basement fractures, depositing them into and above the Rotliegend Sandstone in the shallow Kupferschiefer Sea, which is analogous to the modern northern Caspian Sea.

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