Аннотация:The Santiago Peak volcanics, in the northern Santa Ana Mountains, are the northernmost exposures of the Santiago Peak–Alisitos magmatic arc present along the western edge of the Peninsular Ranges batholith. Remnants of deeply eroded volcanic sequences in the Santa Ana Mountains consist of subaerial basaltic-andesite to rhyolite lavas, rare basalt, welded tuff, and pyroclastic rocks that were emplaced across deformed Middle Jurassic turbidites. Subalkaline lavas have mixed calc-alkaline and tholeiitic affinities. Relatively primitive εSr (−18 to +5) and εNd (+7.5 to +0.1) values for the lavas plot along the mantle array. Silicic lavas have higher εSr and...
