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Zircon U/Pb dates from several granitic intrusives found in the Coyote Mountains (CMs) range from 164.1 to 138.9 Ma. The CMs magmatic activity is too early to be associated with the Cretaceous magmatic activity of the Peninsular Ranges Batholith (~128 to 92 Ma) (Hildebrand and Whalen, 2014b and references therein) but is in the age range of the magmatic activity associated with the Jurassic part of the Nazas Arc in northern Mexico (State of Sonora). The Nazas Arc in Sonora is comprised of two episodes of tectonic activity: an earlier episode from ~ 275 to 221 Ma and a second (Jurassic) episode from ~190 to 150 Ma. (González-León et al., 2017 and references therein). The earliest normal faulting that represents a possibly detachment below the CMs is older than ~17 Ma: an age consistent with Early Miocene extensional tectonics of the Basin and Range in Sonora. Extensional tectonics and subsidence continue to affect the CMs until the start of right-lateral transtensional faulting and uplift associated with the reorganization of the San Andres Fault System at ~1.1 Ma (Steely et al., 2009). With extension of the Basin and Range in Sonora, followed by right-lateral transtensional faulting, the CMs left Sonora and arrive in the western Salton Trough, next to the Peninsular Ranges Batholith (Morgan and Morgan, 2018b). Morgan, G. J., and Morgan, J. R., 2019, Jurassic Intrusives of the Coyote Mountains, western Salton Trough, southern California and their relationship to the Nazas Arc or northern Mexico: Geological Society of America Abstracts with Programs. Vol. 51, No. 4. Figure 1. Location map of the Salton Trough and the Coyote Mountains in California, Arizona, Baja California and Sonora, Mexico. The Salton Trough, an northern extension of the Gulf of California, is bounded by the San Andreas Fault and Old Plate Boundary to the east and, for the most part, by the Peninsular Ranges Batholoth to the west. ABF Agua Blanca Fault, ChM – Chocolate Mountains, CMM – Cargo Muchacho Mountains, EF Elsinore Fault, FC Fish Creek Mountains, GM – Gila Mountains, LA Laguna Sallada, LSF Laguna Salada Fault, Pen. Ran. Bath. Peninsular Ranges Batholith, SAF San Andreas Fault, SJ Sierra de Juarez, SJF San Jacinto Fault, SS Salton Sea. Red star with query is the paleogeographic location of the Coyote Mountains at 5.5 Ma by Winker and Kidwell (1996) in Sonora, Mexico. We agree the paleogeographic location for the CMs was somewhere in Sonora, Mexico. NASA photograph. 2. Simplified sketch map, modified from Titley and Zurcher (2008) showing a part of the Jurassic Nazas Arc with subduction zone (?), San Andreas Fault System, Peninsular Ranges Batholith, Coyote Mountains (CMs) and San Diego (SD). Blue Star is the present location of the CMs. Yellow Diamond is Winker and Kidwell’s (1996) location of the CMs at 5.5 (?) Ma. Blue Question Mark is a possible location for the CMs in Sonora, Mexico. 3. This portion of Morton’s map is a good summary of the geological formations found in and around the CMs. Morton used portions of Dibblee’s (1954) and Christensen’s (1957) maps. Crystalline basement rocks are brown (marbles) and green (schists + Jurassic Intrusions). Simplified interpretations of the basement units: pillow basalts, Paleozoic (?) (Dibblee, 1954; Miller and Dockum (?) 1983) limestones, sandstones, mudstones, cherts, and gravels. Intruding, deforming and metamorphosing these Paleozoic (?) units are Jurassic igneous intrusive units dated with zircons (Morgan and Morgan, 2015). The oldest Tertiary units designated on the map are the volcanics of the Alverson Formation (zircon date of 17.1 Ma, Morgan et al., 2012) colored orange and labeled Mav. Next is the marine and non-marine units of the Imperial Group: colored white and labeled Pi. The non-marine Palm Spring Group is next, colored pink and labeled Pcc and Pcp. Units colored yellow and labeled Qc are Quaternary terrace gravels. The Qc units nonconformally on of the green metamorphics are Christensen’s Quaternary Terraces. We have found these terraces interfingering with the Imperial Group (Morgan and Morgan, 2014, 2015). AC – Alverson Canyon. PG – Painted Gorge. 4. View on the southern CMs showing the locations of the zircon-dated granitic intrusions with roads. Most of the dated granitics are associated with Morton’s green metamorphic unit. AC – Alverson Canyon. OC – Ocotillo Canyon. PG – Painted Gorge. Number Zircon Age-Dates

JURASSIC INTRUSIVES OF THE COYOTE MOUNTAINS, WESTERN SALTON TROUGH, SOUTHERN CALIFORNIA AND THEIR RELATIONSHIP TO THE NAZAS ARC OF NORTHERN MEXICO