Resumen
Serpentinites and fresh or partially serpentinized harzburgite crop out in the western slope of the
North Patagonian Andes of continental Chiloé (41°44?-42°12?S). These rocks are spatially associated with low-grade
metamorphic rocks containing Cenozoic detrital zircons. The metamorphic rocks, together with Devonian metasediments,
have been mapped previously as Late Paleozoic-Triassic metamorfic complex, an age no longer tenable for at least part
of the complex. Transpressional tectonic emplacement of the ultramafic body or bodies is thought to have been related
to activity on the Liquiñe-Ofqui Fault Zone, following a late Oligocene-Early Miocene extensional phase in the forearc
region of the present Andes. This fault zone occurs immediately east of the outcrops of the ultramafic rocks and has
been interpreted previously as generating a hemi-flower or flower structure.