INVESTIGADORES
GREGORI Daniel Alfredo
artículos
Título:
The Puesto Piris Formation: Evidence of basin-development in the North Patagonian Massif during crustal extension associated with Gondwana breakup
Autor/es:
STRAZZERE, LEONARDO; GREGORI, DANIEL A.; BENEDINI, LEONARDO; MARCOS, PAULO; BARROS, MERCEDES; GERALDES, MAURO; PIVETTA, CECILIA PAVÓN
Revista:
Geoscience Frontiers
Editorial:
Elsevier B.V.
Referencias:
Lugar: Beijing; Año: 2018
ISSN:
1674-9871
Resumen:
The Marifil Volcanic Complex, exposed in the eastern North Patagonian Massif, Argentina, includes up to550 m of red conglomerates, sandstones, black siltstones, limestones, and reworked tuff of the PuestoPiris Formation. The basal part of this unit, which was deposited in high-gradient topographic relief, iscomposed of conglomerates and sandstones with thin layers of reworked tuffs. The lithofacies associationsof the basal part indicate that the depositional mechanisms were mantled and gravitational flows.The middle part of the unit consists of fine sandstones, limestones, and black siltstones that weredeposited in low-energy fluvial and lacustrine environments. The outcrops are located along the NEeSWdirection and the major thickest units represented by limestones and siltstones, occur near the southeasternborder of this NEeSW depocenter. Since the rhyolitic and trachytic lava flows and tuffs of theMarifil Volcanic Complex are interbedded with the sedimentary sequences of the Puesto Piris Formation,both units are coeval. Zircon UePb age was obtained for a trachytic lava flow (193.4 3.1 Ma) suggestingthat sedimentation and volcanism are Sinemurian. This extensional episode was recorded in the eastern,western, and southwestern sectors of the North Patagonian Massif, and is possibly associated with theGondwana supercontinent breakup.