Re–Os and U–Pb geochronology of the El Arco porphyry copper deposit, Baja California Mexico: Implications for the Jurassic tectonic setting

Early Cretaceous pre-batholith dextral-transpression in the central Baja California peninsula: the record of the La Unión complex, Baja California, Mexico

“…The youngest U-Pb zircon ages of the prebatholithic rocks in the central belt were reported by Johnson et al (1999b) for an orthogneiss and a volcanic flow (or sill) of 127.8 ± 1.6 and 127.9 ± 1.2 Ma, respectively (Figure 2), located around the northern area of SSPM. In the central belt, the oldest structural fabrics developed before the emplacement of a pluton that yields a thermal ionization mass spectrometry U-Pb zircon age of Goetz (1989); J(1999), Johnson et al (1999a);K(2003), Kimbrough and Moore (2003); K(2010), Kohel and Kimbrough (2010); K(2014), Kimbrough et al (2014b);M(1986M( ), McCormick (1986M(1996), Measures (1996);O(1997), OrtegaRivera et al (1997); P(2012), Peña-Alonso (2012); S(2002), ; S(1969), Silver et al (1969); V(2006), Valencia et al (2006). D1 separates the PRb-related batholithic from prebatholithic rocks.…”

“…Ductilely deformed prebatholithic rocks are exposed instead, but the provenance of these rocks is poorly known because they are scarcely studied (Gastil et al 1975;Peña-Alonso et al 2009) and outcrops are somewhat limited (Torres-Carrillo et al 2011). Lithological characteristics and recent geochronological studies made inside this region, in Nuevo Rosarito (locality 11 in Figure 1a), report Jurassic granitoids and Lower Cretaceous volcanic and volcaniclastic prebatholithic rocks (Peña-Alonso et al 2012), as well as arc-related volcanic and clastic rocks intruded by Jurassic granitoids at El Arco (locality 13 in Figure 1a; Valencia et al 2006;Weber and Martínez 2006). According to their age and lithology, these prebatholithic rocks may be related to the Vizcaíno belt (Kimbrough and Ledesma-Vasquez 2008;Peña-Alonso et al 2012) or to the central belt.…”

“…The identification of Jurassic plutons and Lower Cretaceous volcanic-related rocks along the peninsula (e.g. Johnson et al 1999b;Valencia et al 2006;Peña-Alonso et al 2012;Kimbrough et al 2014b) has complicated the crude 'batholith/prebatholith' classification in such a way that some authors prefer not to use it. However, Early Cretaceous deformation identified in our study area can be used as a possible tectonic limit between prebatholithic and batholithic rocks near the southwestern end of the PRb.…”

Re-Os geochronology of porphyry molybdenum deposit in south segment of Da Hinggan Mountains, Northeast China

“…In recent years, the precise and accurate age determinations of sulfide mineralization have been made in molybdenite. Re-Os dating of molybdenite is a well-established method for obtaining ages for intrusion-associated mineralization (e.g., Valencia et al, 2006;Masterman et al, 2004; This study was supported by the National Natural Science Barra et al, 2003;Selby et al, 2003;Mao et al, 2002Mao et al, , 1999Selby and Creaser, 2001;Stein et al, 2001Stein et al, , 1998Stein et al, , 1997Watanabe and Stein, 2000;Markey et al, 1998;Suzuki et al, 1996).…”

Induced polarization with in-loop transient electromagnetic soundings: A case study of mineral discrimination at El Arco porphyry copper, Mexico

“…4. The deposit is associated with a mid-Jurassic (Valencia et al, 2006;Weber and López-Martínez, 2006) Pelton et al, 1978). Panel "b" has the same axes labels as "a".…”