High <sup>3</sup> He/ <sup>4</sup> He in central Panama reveals a distal connection to the Galápagos plume
David V. Bekaert, Esteban Gazel, Stephen J. Turner, M. D. Behn, J. Marten de Moor, Sabin Zahirovic, Vlad Constantin Manea, Kaj Hoernle, Tobias P. Fischer, Alexander Hammerstrom, Alan Seltzer, Justin T. Kulongoski, Bina Patel, Matthew O. Schrenk, Sæmundur A. Halldórsson, Mayuko Nakagawa, C. J. Ramírez, John A. Krantz, Mustafa Yücel, C. J. Ballentine, Donato Giovannelli, Karen G. Lloyd, Peter H. Barry
Abstract
He values in central Panama are likely derived from the infiltration of a Galápagos plume-like mantle through a slab window that opened ∼8 Mya. Two potential transport mechanisms can explain the connection between the Galápagos plume and the slab window: 1) sublithospheric transport of Galápagos plume material channeled by lithosphere thinning along the Panama Fracture Zone or 2) active upwelling of Galápagos plume material blown by a "mantle wind" toward the CAM. We present a model of global mantle flow that supports the second mechanism, whereby most of the eastward transport of Galápagos plume material occurs in the shallow asthenosphere. These findings underscore the potential for lateral mantle flow to transport mantle geochemical heterogeneities thousands of kilometers away from plume conduits.