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This three-day trip examines Eocene volcanic and intrusive centers in and around the Carlin trend and the relation of Eocene magmatism and tectonism to Carlin-type deposits (Fig. 1, p.58). Until recently, the prevalent view was that Carlin-type deposits in northern Nevada and Utah were most likely Cretaceous in age, related to metamorphism and/or extension, and formed at depths of ~5 km (Kuehn and Rose, 1992; Arehart et al., 1993; Wilson and Parry, 1995; Arehart,1996; Drews-Armitage et al., 1996; Ilchik and Barton, 1997). Our interpretation is that the deposits are Eocene, that Eocene magmatism was the heat source and possibly the source of some metals and fluids, and that the deposits formed at depths no greater than about 2 km(Henry and Boden, 1998; Henry and Ressel, 2000; Ressel et al., 2000a, b). Day 1 examines unaltered Eocene rocks in the Emigrant Pass volcanic field, which is adjacent to the Carlin trend. Day2 looks at altered and mineralized Eocene dikes in the northern Carlin trend where Eocene intrusive rocks are intimately associated with ore. Day 3 examines a mix of unaltered and altered-mineralized rocks in the Tuscarora volcanic field and the Tuscarora epithermal, volcanic-hosted precious metal deposit.