Palaeomagnetism of the Puerto Vallarta intrusive complex and the accretion of the Guerrero terrain, Mexico

摘要: Abstract The batholith exposed around Puerto Vallarta is part of the Guerrero tectonostratigraphic terrain, presumably accreted to Mexico during Laramide orogenic phase. Fourteen sites on this were studied palaeomagnetically and geochemically. Nine define a paleopole at 76.6°N, 181.8°E, with α95 = 6.6°, coinciding reference pole for stable North America. It proposed that no important movements region relative America have occurred since emplacement intrusive rocks ∼ 80 Ma ago. This would mean terrain was Mexican continental margin before time. Geochemical data support interpretation, characterizing as volcanic-arc granites intruded an active margin.