ABSTRACT The Laramide continental arc formed in southwestern North America at about the same time the Sierra Nevadan arc was shutting down, and the Laramide arc was active concurrent with the progress of the Laramide orogeny, from ca. 80 Ma to ca. 45 Ma. East-central Arizona offers an excellent opportunity to explore aspects of tectonics, structural geology, magmatism, and hydrothermal systems in a segment of the Laramide arc that is exceptionally well endowed with porphyry copper deposits. The structure of this region is especially complicated, with multiple generations of normal faults commonly superimposed on originally moderate-angle reverse faults with associated fault-propagation folds. A large new porphyry copper deposit, Resolution, was discovered near Superior in the mid-1990s. The discovery started a new round of development in the mining life cycle at the Resolution deposit; in the region, it contributed to copper exploration again becoming vigorous in the last decade. In the years since discovery of Resolution, important new scientific insights have been gained, including at the regional scale. Post-ore crustal extension exposed multiple levels of Laramide and older igneous and hydrothermal systems at the surface where they can be more easily mapped and sampled, and palinspastic reconstructions of post-mineral normal faulting permit the exposures to be restored to their original positions. The porphyry-related products that are observed at higher levels include local advanced argillic alteration and Cordilleran-style veins and associated mantos, such as at the Magma mine, Resolution deposit, and Old Dominion mine in the shallowest levels of the Superior-Globe-Miami area. Most porphyry copper ore bodies were developed at intermediate depths, where porphyry intrusions exhibit sericitic and potassic alteration and carbonate rocks were converted to skarn, such as in the heart of the Miami-Inspiration, Resolution, Ray, and Christmas deposits. Plutonic rocks are exposed at deeper paleodepths, where pegmatites, quartz veins, and greisen muscovite are locally observed, especially directly beneath porphyry copper orebodies, as in the Schultze and Granite Mountain plutons. Likewise, sodic-calcic alteration may be developed on the deep flanks of porphyry systems, such as adjacent to the Tea Cup pluton. Subsequent Cenozoic extension variously buried or exhumed the hypogene portions of these hydrothermal systems, leading to the development of various supergene products, both in situ and exotic.

Abstract A glaciated margin is a continental margin that has been occupied by a large ice mass, such that glacial processes and slope processes conspire to produce a thick sedimentary record. Ice masses take an active role in sculpting, redistributing and reorganizing the sediment that they erode on the continental shelf, and act as a supply route to large fan systems (e.g. trough mouth fans, submarine fans) on the continental slope and continental rise. To many researchers, the term ‘glaciated margin’ is synonymous with modern day areas fringing Antarctica and the Arctic shelf systems, yet the geological record contains ancient examples ranging in age from Precambrian to Cenozoic. In the pre-Pleistocene record, there is a tendency for the configuration of the tectonic plates to become increasingly obscure with age. For instance, in the Neoproterozoic record, not everyone agrees on the location of rift margins and some fundamental continental boundaries remain unclear. Given these issues, this introductory paper has two simple aims: (1) to provide a brief commentary of relevant Geological Society publications on glaciated margins, with the landmark papers highlighted and (2) to explain the contents of this volume.

In this section, only the stratigraphy of the rocks deposited before and during the violent events of the Cuban orogeny will be described. The deformation probably reached its peak during the early–middle Eocene. The reason for this rather indefinite time assignment is that no index faunas have been found to separate the middle from the lower Eocene in the syn-orogenic flysch sediments, much less in the wildflysch that characterizes the culmination of the orogeny. The only evidence that the orogeny is pre–upper Eocene is a widespread, well-defined unconformity below an upper Eocene orbitoid-rich limestone that, although occasionally deformed, was not involved in the strong orogenic tectonism. As will be seen later, the tectonic events that marked the end of the orogeny were not exactly synchronous all over Cuba. In the south, the orogenic deformation started in the late Maastrichtian to Paleocene, whereas in the north, the deformation started in the early Eocene. The molasse (or erosion of already inactive topography) cycle startedinthe southinthe early Eocene while thrusting proceeded in the north in the middle Eocene with the production of associated flysch deposits (or erosion of an active orogenic front). The mo-lasse was carried piggyback by the northward advancing thrusts while contemporaneous flysch was being generated in the north. Stratigraphy and structure are intimately intertwined in Cuba; the significance of structural features can be understood only through the knowledge of stratigraphy. Therefore, in this chapter, the stratigraphy will be described first to establish a plausible preorogenic paleogeography.As previously mentioned, many

In this chapter, only the surface structures that characterize the various tectonic styles will be described. Examples of subsurface structures will be shown, although very little has been published on this subject. This chapter will describe the structures in the following order: central Cuba, western Cuba, northern Cuba, and eastern Cuba.